Replace godep with dep

vendor/github.com/prometheus/client_golang/.gitignore

@@ -0,0 +1,26 @@
+# Compiled Object files, Static and Dynamic libs (Shared Objects)
+*.o
+*.a
+*.so
+
+# Folders
+_obj
+_test
+
+# Architecture specific extensions/prefixes
+*.[568vq]
+[568vq].out
+
+*.cgo1.go
+*.cgo2.c
+_cgo_defun.c
+_cgo_gotypes.go
+_cgo_export.*
+
+_testmain.go
+
+*.exe
+
+*~
+*#
+.build

vendor/github.com/prometheus/client_golang/.travis.yml

@@ -0,0 +1,9 @@
+sudo: false
+language: go
+
+go:
+ - 1.5.4
+ - 1.6.2
+
+script:
+ - go test -short ./... 

vendor/github.com/prometheus/client_golang/AUTHORS.md

@@ -8,6 +8,11 @@ Maintainers of this repository:
 The following individuals have contributed code to this repository
 (listed in alphabetical order):
 
+* Bernerd Schaefer <bj.schaefer@gmail.com>
 * Björn Rabenstein <beorn@soundcloud.com>
+* Daniel Bornkessel <daniel@soundcloud.com>
+* Jeff Younker <jeff@drinktomi.com>
+* Julius Volz <julius.volz@gmail.com>
 * Matt T. Proud <matt.proud@gmail.com>
 * Tobias Schmidt <ts@soundcloud.com>
+

vendor/github.com/prometheus/client_golang/CHANGELOG.md

@@ -0,0 +1,109 @@
+## 0.8.0 / 2016-08-17
+* [CHANGE] Registry is doing more consistency checks. This might break
+  existing setups that used to export inconsistent metrics.
+* [CHANGE] Pushing to Pushgateway moved to package `push` and changed to allow
+  arbitrary grouping.
+* [CHANGE] Removed `SelfCollector`.
+* [CHANGE] Removed `PanicOnCollectError` and `EnableCollectChecks` methods.
+* [CHANGE] Moved packages to the prometheus/common repo: `text`, `model`,
+  `extraction`.
+* [CHANGE] Deprecated a number of functions.
+* [FEATURE] Allow custom registries. Added `Registerer` and `Gatherer`
+  interfaces.
+* [FEATURE] Separated HTTP exposition, allowing custom HTTP handlers (package
+  `promhttp`) and enabling the creation of other exposition mechanisms.
+* [FEATURE] `MustRegister` is variadic now, allowing registration of many
+  collectors in one call.
+* [FEATURE] Added HTTP API v1 package.
+* [ENHANCEMENT] Numerous documentation improvements.
+* [ENHANCEMENT] Improved metric sorting.
+* [ENHANCEMENT] Inlined fnv64a hashing for improved performance.
+* [ENHANCEMENT] Several test improvements.
+* [BUGFIX] Handle collisions in MetricVec.
+
+## 0.7.0 / 2015-07-27
+* [CHANGE] Rename ExporterLabelPrefix to ExportedLabelPrefix.
+* [BUGFIX] Closed gaps in metric consistency check.
+* [BUGFIX] Validate LabelName/LabelSet on JSON unmarshaling.
+* [ENHANCEMENT] Document the possibility to create "empty" metrics in
+  a metric vector.
+* [ENHANCEMENT] Fix and clarify various doc comments and the README.md.
+* [ENHANCEMENT] (Kind of) solve "The Proxy Problem" of http.InstrumentHandler.
+* [ENHANCEMENT] Change responseWriterDelegator.written to int64.
+
+## 0.6.0 / 2015-06-01
+* [CHANGE] Rename process_goroutines to go_goroutines.
+* [ENHANCEMENT] Validate label names during YAML decoding.
+* [ENHANCEMENT] Add LabelName regular expression.
+* [BUGFIX] Ensure alignment of struct members for 32-bit systems.
+
+## 0.5.0 / 2015-05-06
+* [BUGFIX] Removed a weakness in the fingerprinting aka signature code.
+  This makes fingerprinting slower and more allocation-heavy, but the
+  weakness was too severe to be tolerated.
+* [CHANGE] As a result of the above, Metric.Fingerprint is now returning
+  a different fingerprint. To keep the same fingerprint, the new method
+  Metric.FastFingerprint was introduced, which will be used by the
+  Prometheus server for storage purposes (implying that a collision
+  detection has to be added, too).
+* [ENHANCEMENT] The Metric.Equal and Metric.Before do not depend on
+  fingerprinting anymore, removing the possibility of an undetected
+  fingerprint collision.
+* [FEATURE] The Go collector in the exposition library includes garbage
+  collection stats.
+* [FEATURE] The exposition library allows to create constant "throw-away"
+  summaries and histograms.
+* [CHANGE] A number of new reserved labels and prefixes.
+
+## 0.4.0 / 2015-04-08
+* [CHANGE] Return NaN when Summaries have no observations yet.
+* [BUGFIX] Properly handle Summary decay upon Write().
+* [BUGFIX] Fix the documentation link to the consumption library.
+* [FEATURE] Allow the metric family injection hook to merge with existing
+  metric families.
+* [ENHANCEMENT] Removed cgo dependency and conditional compilation of procfs.
+* [MAINTENANCE] Adjusted to changes in matttproud/golang_protobuf_extensions.
+
+## 0.3.2 / 2015-03-11
+* [BUGFIX] Fixed the receiver type of COWMetric.Set(). This method is
+  only used by the Prometheus server internally.
+* [CLEANUP] Added licenses of vendored code left out by godep.
+
+## 0.3.1 / 2015-03-04
+* [ENHANCEMENT] Switched fingerprinting functions from own free list to
+  sync.Pool.
+* [CHANGE] Makefile uses Go 1.4.2 now (only relevant for examples and tests).
+
+## 0.3.0 / 2015-03-03
+* [CHANGE] Changed the fingerprinting for metrics. THIS WILL INVALIDATE ALL
+  PERSISTED FINGERPRINTS. IF YOU COMPILE THE PROMETHEUS SERVER WITH THIS
+  VERSION, YOU HAVE TO WIPE THE PREVIOUSLY CREATED STORAGE.
+* [CHANGE] LabelValuesToSignature removed. (Nobody had used it, and it was
+  arguably broken.)
+* [CHANGE] Vendored dependencies. Those are only used by the Makefile. If
+  client_golang is used as a library, the vendoring will stay out of your way.
+* [BUGFIX] Remove a weakness in the fingerprinting for metrics. (This made
+  the fingerprinting change above necessary.)
+* [FEATURE] Added new fingerprinting functions SignatureForLabels and
+  SignatureWithoutLabels to be used by the Prometheus server. These functions
+  require fewer allocations than the ones currently used by the server.
+
+## 0.2.0 / 2015-02-23
+* [FEATURE] Introduce new Histagram metric type.
+* [CHANGE] Ignore process collector errors for now (better error handling
+  pending).
+* [CHANGE] Use clear error interface for process pidFn.
+* [BUGFIX] Fix Go download links for several archs and OSes.
+* [ENHANCEMENT] Massively improve Gauge and Counter performance.
+* [ENHANCEMENT] Catch illegal label names for summaries in histograms.
+* [ENHANCEMENT] Reduce allocations during fingerprinting.
+* [ENHANCEMENT] Remove cgo dependency. procfs package will only be included if
+  both cgo is available and the build is for an OS with procfs.
+* [CLEANUP] Clean up code style issues.
+* [CLEANUP] Mark slow test as such and exclude them from travis.
+* [CLEANUP] Update protobuf library package name.
+* [CLEANUP] Updated vendoring of beorn7/perks.
+
+## 0.1.0 / 2015-02-02
+* [CLEANUP] Introduced semantic versioning and changelog. From now on,
+  changes will be reported in this file.

vendor/github.com/prometheus/client_golang/CONTRIBUTING.md

@@ -0,0 +1,18 @@
+# Contributing
+
+Prometheus uses GitHub to manage reviews of pull requests.
+
+* If you have a trivial fix or improvement, go ahead and create a pull
+  request, addressing (with `@...`) one or more of the maintainers
+  (see [AUTHORS.md](AUTHORS.md)) in the description of the pull request.
+
+* If you plan to do something more involved, first discuss your ideas
+  on our [mailing list](https://groups.google.com/forum/?fromgroups#!forum/prometheus-developers).
+  This will avoid unnecessary work and surely give you and us a good deal
+  of inspiration.
+
+* Relevant coding style guidelines are the [Go Code Review
+  Comments](https://code.google.com/p/go-wiki/wiki/CodeReviewComments)
+  and the _Formatting and style_ section of Peter Bourgon's [Go: Best
+  Practices for Production
+  Environments](http://peter.bourgon.org/go-in-production/#formatting-and-style).

vendor/github.com/prometheus/client_golang/README.md

@@ -0,0 +1,45 @@
+# Prometheus Go client library
+
+[![Build Status](https://travis-ci.org/prometheus/client_golang.svg?branch=master)](https://travis-ci.org/prometheus/client_golang)
+
+This is the [Go](http://golang.org) client library for
+[Prometheus](http://prometheus.io). It has two separate parts, one for
+instrumenting application code, and one for creating clients that talk to the
+Prometheus HTTP API.
+
+## Instrumenting applications
+
+[![code-coverage](http://gocover.io/_badge/github.com/prometheus/client_golang/prometheus)](http://gocover.io/github.com/prometheus/client_golang/prometheus) [![go-doc](https://godoc.org/github.com/prometheus/client_golang/prometheus?status.svg)](https://godoc.org/github.com/prometheus/client_golang/prometheus)
+
+The
+[`prometheus` directory](https://github.com/prometheus/client_golang/tree/master/prometheus)
+contains the instrumentation library. See the
+[best practices section](http://prometheus.io/docs/practices/naming/) of the
+Prometheus documentation to learn more about instrumenting applications.
+
+The
+[`examples` directory](https://github.com/prometheus/client_golang/tree/master/examples)
+contains simple examples of instrumented code.
+
+## Client for the Prometheus HTTP API
+
+[![code-coverage](http://gocover.io/_badge/github.com/prometheus/client_golang/api/prometheus)](http://gocover.io/github.com/prometheus/client_golang/api/prometheus) [![go-doc](https://godoc.org/github.com/prometheus/client_golang/api/prometheus?status.svg)](https://godoc.org/github.com/prometheus/client_golang/api/prometheus)
+
+The
+[`api/prometheus` directory](https://github.com/prometheus/client_golang/tree/master/api/prometheus)
+contains the client for the
+[Prometheus HTTP API](http://prometheus.io/docs/querying/api/). It allows you
+to write Go applications that query time series data from a Prometheus server.
+
+## Where is `model`, `extraction`, and `text`?
+
+The `model` packages has been moved to
+[`prometheus/common/model`](https://github.com/prometheus/common/tree/master/model).
+
+The `extraction` and `text` packages are now contained in
+[`prometheus/common/expfmt`](https://github.com/prometheus/common/tree/master/expfmt).
+
+## Contributing and community
+
+See the [contributing guidelines](CONTRIBUTING.md) and the
+[Community section](http://prometheus.io/community/) of the homepage.

vendor/github.com/prometheus/client_golang/VERSION

@@ -0,0 +1 @@
+0.8.0

vendor/github.com/prometheus/client_golang/api/prometheus/api.go

@@ -0,0 +1,345 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package prometheus provides bindings to the Prometheus HTTP API:
+// http://prometheus.io/docs/querying/api/
+package prometheus
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net"
+	"net/http"
+	"net/url"
+	"path"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/prometheus/common/model"
+	"golang.org/x/net/context"
+	"golang.org/x/net/context/ctxhttp"
+)
+
+const (
+	statusAPIError = 422
+	apiPrefix      = "/api/v1"
+
+	epQuery       = "/query"
+	epQueryRange  = "/query_range"
+	epLabelValues = "/label/:name/values"
+	epSeries      = "/series"
+)
+
+type ErrorType string
+
+const (
+	// The different API error types.
+	ErrBadData     ErrorType = "bad_data"
+	ErrTimeout               = "timeout"
+	ErrCanceled              = "canceled"
+	ErrExec                  = "execution"
+	ErrBadResponse           = "bad_response"
+)
+
+// Error is an error returned by the API.
+type Error struct {
+	Type ErrorType
+	Msg  string
+}
+
+func (e *Error) Error() string {
+	return fmt.Sprintf("%s: %s", e.Type, e.Msg)
+}
+
+// CancelableTransport is like net.Transport but provides
+// per-request cancelation functionality.
+type CancelableTransport interface {
+	http.RoundTripper
+	CancelRequest(req *http.Request)
+}
+
+var DefaultTransport CancelableTransport = &http.Transport{
+	Proxy: http.ProxyFromEnvironment,
+	Dial: (&net.Dialer{
+		Timeout:   30 * time.Second,
+		KeepAlive: 30 * time.Second,
+	}).Dial,
+	TLSHandshakeTimeout: 10 * time.Second,
+}
+
+// Config defines configuration parameters for a new client.
+type Config struct {
+	// The address of the Prometheus to connect to.
+	Address string
+
+	// Transport is used by the Client to drive HTTP requests. If not
+	// provided, DefaultTransport will be used.
+	Transport CancelableTransport
+}
+
+func (cfg *Config) transport() CancelableTransport {
+	if cfg.Transport == nil {
+		return DefaultTransport
+	}
+	return cfg.Transport
+}
+
+type Client interface {
+	url(ep string, args map[string]string) *url.URL
+	do(context.Context, *http.Request) (*http.Response, []byte, error)
+}
+
+// New returns a new Client.
+//
+// It is safe to use the returned Client from multiple goroutines.
+func New(cfg Config) (Client, error) {
+	u, err := url.Parse(cfg.Address)
+	if err != nil {
+		return nil, err
+	}
+	u.Path = strings.TrimRight(u.Path, "/") + apiPrefix
+
+	return &httpClient{
+		endpoint:  u,
+		transport: cfg.transport(),
+	}, nil
+}
+
+type httpClient struct {
+	endpoint  *url.URL
+	transport CancelableTransport
+}
+
+func (c *httpClient) url(ep string, args map[string]string) *url.URL {
+	p := path.Join(c.endpoint.Path, ep)
+
+	for arg, val := range args {
+		arg = ":" + arg
+		p = strings.Replace(p, arg, val, -1)
+	}
+
+	u := *c.endpoint
+	u.Path = p
+
+	return &u
+}
+
+func (c *httpClient) do(ctx context.Context, req *http.Request) (*http.Response, []byte, error) {
+	resp, err := ctxhttp.Do(ctx, &http.Client{Transport: c.transport}, req)
+
+	defer func() {
+		if resp != nil {
+			resp.Body.Close()
+		}
+	}()
+
+	if err != nil {
+		return nil, nil, err
+	}
+
+	var body []byte
+	done := make(chan struct{})
+	go func() {
+		body, err = ioutil.ReadAll(resp.Body)
+		close(done)
+	}()
+
+	select {
+	case <-ctx.Done():
+		err = resp.Body.Close()
+		<-done
+		if err == nil {
+			err = ctx.Err()
+		}
+	case <-done:
+	}
+
+	return resp, body, err
+}
+
+// apiClient wraps a regular client and processes successful API responses.
+// Successful also includes responses that errored at the API level.
+type apiClient struct {
+	Client
+}
+
+type apiResponse struct {
+	Status    string          `json:"status"`
+	Data      json.RawMessage `json:"data"`
+	ErrorType ErrorType       `json:"errorType"`
+	Error     string          `json:"error"`
+}
+
+func (c apiClient) do(ctx context.Context, req *http.Request) (*http.Response, []byte, error) {
+	resp, body, err := c.Client.do(ctx, req)
+	if err != nil {
+		return resp, body, err
+	}
+
+	code := resp.StatusCode
+
+	if code/100 != 2 && code != statusAPIError {
+		return resp, body, &Error{
+			Type: ErrBadResponse,
+			Msg:  fmt.Sprintf("bad response code %d", resp.StatusCode),
+		}
+	}
+
+	var result apiResponse
+
+	if err = json.Unmarshal(body, &result); err != nil {
+		return resp, body, &Error{
+			Type: ErrBadResponse,
+			Msg:  err.Error(),
+		}
+	}
+
+	if (code == statusAPIError) != (result.Status == "error") {
+		err = &Error{
+			Type: ErrBadResponse,
+			Msg:  "inconsistent body for response code",
+		}
+	}
+
+	if code == statusAPIError && result.Status == "error" {
+		err = &Error{
+			Type: result.ErrorType,
+			Msg:  result.Error,
+		}
+	}
+
+	return resp, []byte(result.Data), err
+}
+
+// Range represents a sliced time range.
+type Range struct {
+	// The boundaries of the time range.
+	Start, End time.Time
+	// The maximum time between two slices within the boundaries.
+	Step time.Duration
+}
+
+// queryResult contains result data for a query.
+type queryResult struct {
+	Type   model.ValueType `json:"resultType"`
+	Result interface{}     `json:"result"`
+
+	// The decoded value.
+	v model.Value
+}
+
+func (qr *queryResult) UnmarshalJSON(b []byte) error {
+	v := struct {
+		Type   model.ValueType `json:"resultType"`
+		Result json.RawMessage `json:"result"`
+	}{}
+
+	err := json.Unmarshal(b, &v)
+	if err != nil {
+		return err
+	}
+
+	switch v.Type {
+	case model.ValScalar:
+		var sv model.Scalar
+		err = json.Unmarshal(v.Result, &sv)
+		qr.v = &sv
+
+	case model.ValVector:
+		var vv model.Vector
+		err = json.Unmarshal(v.Result, &vv)
+		qr.v = vv
+
+	case model.ValMatrix:
+		var mv model.Matrix
+		err = json.Unmarshal(v.Result, &mv)
+		qr.v = mv
+
+	default:
+		err = fmt.Errorf("unexpected value type %q", v.Type)
+	}
+	return err
+}
+
+// QueryAPI provides bindings the Prometheus's query API.
+type QueryAPI interface {
+	// Query performs a query for the given time.
+	Query(ctx context.Context, query string, ts time.Time) (model.Value, error)
+	// Query performs a query for the given range.
+	QueryRange(ctx context.Context, query string, r Range) (model.Value, error)
+}
+
+// NewQueryAPI returns a new QueryAPI for the client.
+//
+// It is safe to use the returned QueryAPI from multiple goroutines.
+func NewQueryAPI(c Client) QueryAPI {
+	return &httpQueryAPI{client: apiClient{c}}
+}
+
+type httpQueryAPI struct {
+	client Client
+}
+
+func (h *httpQueryAPI) Query(ctx context.Context, query string, ts time.Time) (model.Value, error) {
+	u := h.client.url(epQuery, nil)
+	q := u.Query()
+
+	q.Set("query", query)
+	q.Set("time", ts.Format(time.RFC3339Nano))
+
+	u.RawQuery = q.Encode()
+
+	req, _ := http.NewRequest("GET", u.String(), nil)
+
+	_, body, err := h.client.do(ctx, req)
+	if err != nil {
+		return nil, err
+	}
+
+	var qres queryResult
+	err = json.Unmarshal(body, &qres)
+
+	return model.Value(qres.v), err
+}
+
+func (h *httpQueryAPI) QueryRange(ctx context.Context, query string, r Range) (model.Value, error) {
+	u := h.client.url(epQueryRange, nil)
+	q := u.Query()
+
+	var (
+		start = r.Start.Format(time.RFC3339Nano)
+		end   = r.End.Format(time.RFC3339Nano)
+		step  = strconv.FormatFloat(r.Step.Seconds(), 'f', 3, 64)
+	)
+
+	q.Set("query", query)
+	q.Set("start", start)
+	q.Set("end", end)
+	q.Set("step", step)
+
+	u.RawQuery = q.Encode()
+
+	req, _ := http.NewRequest("GET", u.String(), nil)
+
+	_, body, err := h.client.do(ctx, req)
+	if err != nil {
+		return nil, err
+	}
+
+	var qres queryResult
+	err = json.Unmarshal(body, &qres)
+
+	return model.Value(qres.v), err
+}

vendor/github.com/prometheus/client_golang/api/prometheus/api_test.go

@@ -0,0 +1,453 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+	"reflect"
+	"testing"
+	"time"
+
+	"github.com/prometheus/common/model"
+	"golang.org/x/net/context"
+)
+
+func TestConfig(t *testing.T) {
+	c := Config{}
+	if c.transport() != DefaultTransport {
+		t.Fatalf("expected default transport for nil Transport field")
+	}
+}
+
+func TestClientURL(t *testing.T) {
+	tests := []struct {
+		address  string
+		endpoint string
+		args     map[string]string
+		expected string
+	}{
+		{
+			address:  "http://localhost:9090",
+			endpoint: "/test",
+			expected: "http://localhost:9090/test",
+		},
+		{
+			address:  "http://localhost",
+			endpoint: "/test",
+			expected: "http://localhost/test",
+		},
+		{
+			address:  "http://localhost:9090",
+			endpoint: "test",
+			expected: "http://localhost:9090/test",
+		},
+		{
+			address:  "http://localhost:9090/prefix",
+			endpoint: "/test",
+			expected: "http://localhost:9090/prefix/test",
+		},
+		{
+			address:  "https://localhost:9090/",
+			endpoint: "/test/",
+			expected: "https://localhost:9090/test",
+		},
+		{
+			address:  "http://localhost:9090",
+			endpoint: "/test/:param",
+			args: map[string]string{
+				"param": "content",
+			},
+			expected: "http://localhost:9090/test/content",
+		},
+		{
+			address:  "http://localhost:9090",
+			endpoint: "/test/:param/more/:param",
+			args: map[string]string{
+				"param": "content",
+			},
+			expected: "http://localhost:9090/test/content/more/content",
+		},
+		{
+			address:  "http://localhost:9090",
+			endpoint: "/test/:param/more/:foo",
+			args: map[string]string{
+				"param": "content",
+				"foo":   "bar",
+			},
+			expected: "http://localhost:9090/test/content/more/bar",
+		},
+		{
+			address:  "http://localhost:9090",
+			endpoint: "/test/:param",
+			args: map[string]string{
+				"nonexistant": "content",
+			},
+			expected: "http://localhost:9090/test/:param",
+		},
+	}
+
+	for _, test := range tests {
+		ep, err := url.Parse(test.address)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		hclient := &httpClient{
+			endpoint:  ep,
+			transport: DefaultTransport,
+		}
+
+		u := hclient.url(test.endpoint, test.args)
+		if u.String() != test.expected {
+			t.Errorf("unexpected result: got %s, want %s", u, test.expected)
+			continue
+		}
+
+		// The apiClient must return exactly the same result as the httpClient.
+		aclient := &apiClient{hclient}
+
+		u = aclient.url(test.endpoint, test.args)
+		if u.String() != test.expected {
+			t.Errorf("unexpected result: got %s, want %s", u, test.expected)
+		}
+	}
+}
+
+type testClient struct {
+	*testing.T
+
+	ch  chan apiClientTest
+	req *http.Request
+}
+
+type apiClientTest struct {
+	code     int
+	response interface{}
+	expected string
+	err      *Error
+}
+
+func (c *testClient) url(ep string, args map[string]string) *url.URL {
+	return nil
+}
+
+func (c *testClient) do(ctx context.Context, req *http.Request) (*http.Response, []byte, error) {
+	if ctx == nil {
+		c.Fatalf("context was not passed down")
+	}
+	if req != c.req {
+		c.Fatalf("request was not passed down")
+	}
+
+	test := <-c.ch
+
+	var b []byte
+	var err error
+
+	switch v := test.response.(type) {
+	case string:
+		b = []byte(v)
+	default:
+		b, err = json.Marshal(v)
+		if err != nil {
+			c.Fatal(err)
+		}
+	}
+
+	resp := &http.Response{
+		StatusCode: test.code,
+	}
+
+	return resp, b, nil
+}
+
+func TestAPIClientDo(t *testing.T) {
+	tests := []apiClientTest{
+		{
+			response: &apiResponse{
+				Status:    "error",
+				Data:      json.RawMessage(`null`),
+				ErrorType: ErrBadData,
+				Error:     "failed",
+			},
+			err: &Error{
+				Type: ErrBadData,
+				Msg:  "failed",
+			},
+			code:     statusAPIError,
+			expected: `null`,
+		},
+		{
+			response: &apiResponse{
+				Status:    "error",
+				Data:      json.RawMessage(`"test"`),
+				ErrorType: ErrTimeout,
+				Error:     "timed out",
+			},
+			err: &Error{
+				Type: ErrTimeout,
+				Msg:  "timed out",
+			},
+			code:     statusAPIError,
+			expected: `test`,
+		},
+		{
+			response: "bad json",
+			err: &Error{
+				Type: ErrBadResponse,
+				Msg:  "bad response code 400",
+			},
+			code: http.StatusBadRequest,
+		},
+		{
+			response: "bad json",
+			err: &Error{
+				Type: ErrBadResponse,
+				Msg:  "invalid character 'b' looking for beginning of value",
+			},
+			code: statusAPIError,
+		},
+		{
+			response: &apiResponse{
+				Status: "success",
+				Data:   json.RawMessage(`"test"`),
+			},
+			err: &Error{
+				Type: ErrBadResponse,
+				Msg:  "inconsistent body for response code",
+			},
+			code: statusAPIError,
+		},
+		{
+			response: &apiResponse{
+				Status:    "success",
+				Data:      json.RawMessage(`"test"`),
+				ErrorType: ErrTimeout,
+				Error:     "timed out",
+			},
+			err: &Error{
+				Type: ErrBadResponse,
+				Msg:  "inconsistent body for response code",
+			},
+			code: statusAPIError,
+		},
+		{
+			response: &apiResponse{
+				Status:    "error",
+				Data:      json.RawMessage(`"test"`),
+				ErrorType: ErrTimeout,
+				Error:     "timed out",
+			},
+			err: &Error{
+				Type: ErrBadResponse,
+				Msg:  "inconsistent body for response code",
+			},
+			code: http.StatusOK,
+		},
+	}
+
+	tc := &testClient{
+		T:   t,
+		ch:  make(chan apiClientTest, 1),
+		req: &http.Request{},
+	}
+	client := &apiClient{tc}
+
+	for _, test := range tests {
+
+		tc.ch <- test
+
+		_, body, err := client.do(context.Background(), tc.req)
+
+		if test.err != nil {
+			if err == nil {
+				t.Errorf("expected error %q but got none", test.err)
+				continue
+			}
+			if test.err.Error() != err.Error() {
+				t.Errorf("unexpected error: want %q, got %q", test.err, err)
+			}
+			continue
+		}
+		if err != nil {
+			t.Errorf("unexpeceted error %s", err)
+			continue
+		}
+
+		want, got := test.expected, string(body)
+		if want != got {
+			t.Errorf("unexpected body: want %q, got %q", want, got)
+		}
+	}
+}
+
+type apiTestClient struct {
+	*testing.T
+	curTest apiTest
+}
+
+type apiTest struct {
+	do    func() (interface{}, error)
+	inErr error
+	inRes interface{}
+
+	reqPath   string
+	reqParam  url.Values
+	reqMethod string
+	res       interface{}
+	err       error
+}
+
+func (c *apiTestClient) url(ep string, args map[string]string) *url.URL {
+	u := &url.URL{
+		Host: "test:9090",
+		Path: apiPrefix + ep,
+	}
+	return u
+}
+
+func (c *apiTestClient) do(ctx context.Context, req *http.Request) (*http.Response, []byte, error) {
+
+	test := c.curTest
+
+	if req.URL.Path != test.reqPath {
+		c.Errorf("unexpected request path: want %s, got %s", test.reqPath, req.URL.Path)
+	}
+	if req.Method != test.reqMethod {
+		c.Errorf("unexpected request method: want %s, got %s", test.reqMethod, req.Method)
+	}
+
+	b, err := json.Marshal(test.inRes)
+	if err != nil {
+		c.Fatal(err)
+	}
+
+	resp := &http.Response{}
+	if test.inErr != nil {
+		resp.StatusCode = statusAPIError
+	} else {
+		resp.StatusCode = http.StatusOK
+	}
+
+	return resp, b, test.inErr
+}
+
+func TestAPIs(t *testing.T) {
+
+	testTime := time.Now()
+
+	client := &apiTestClient{T: t}
+
+	queryApi := &httpQueryAPI{
+		client: client,
+	}
+
+	doQuery := func(q string, ts time.Time) func() (interface{}, error) {
+		return func() (interface{}, error) {
+			return queryApi.Query(context.Background(), q, ts)
+		}
+	}
+
+	doQueryRange := func(q string, rng Range) func() (interface{}, error) {
+		return func() (interface{}, error) {
+			return queryApi.QueryRange(context.Background(), q, rng)
+		}
+	}
+
+	queryTests := []apiTest{
+		{
+			do: doQuery("2", testTime),
+			inRes: &queryResult{
+				Type: model.ValScalar,
+				Result: &model.Scalar{
+					Value:     2,
+					Timestamp: model.TimeFromUnix(testTime.Unix()),
+				},
+			},
+
+			reqMethod: "GET",
+			reqPath:   "/api/v1/query",
+			reqParam: url.Values{
+				"query": []string{"2"},
+				"time":  []string{testTime.Format(time.RFC3339Nano)},
+			},
+			res: &model.Scalar{
+				Value:     2,
+				Timestamp: model.TimeFromUnix(testTime.Unix()),
+			},
+		},
+		{
+			do:    doQuery("2", testTime),
+			inErr: fmt.Errorf("some error"),
+
+			reqMethod: "GET",
+			reqPath:   "/api/v1/query",
+			reqParam: url.Values{
+				"query": []string{"2"},
+				"time":  []string{testTime.Format(time.RFC3339Nano)},
+			},
+			err: fmt.Errorf("some error"),
+		},
+
+		{
+			do: doQueryRange("2", Range{
+				Start: testTime.Add(-time.Minute),
+				End:   testTime,
+				Step:  time.Minute,
+			}),
+			inErr: fmt.Errorf("some error"),
+
+			reqMethod: "GET",
+			reqPath:   "/api/v1/query_range",
+			reqParam: url.Values{
+				"query": []string{"2"},
+				"start": []string{testTime.Add(-time.Minute).Format(time.RFC3339Nano)},
+				"end":   []string{testTime.Format(time.RFC3339Nano)},
+				"step":  []string{time.Minute.String()},
+			},
+			err: fmt.Errorf("some error"),
+		},
+	}
+
+	var tests []apiTest
+	tests = append(tests, queryTests...)
+
+	for _, test := range tests {
+		client.curTest = test
+
+		res, err := test.do()
+
+		if test.err != nil {
+			if err == nil {
+				t.Errorf("expected error %q but got none", test.err)
+				continue
+			}
+			if err.Error() != test.err.Error() {
+				t.Errorf("unexpected error: want %s, got %s", test.err, err)
+			}
+			continue
+		}
+		if err != nil {
+			t.Errorf("unexpected error: %s", err)
+			continue
+		}
+
+		if !reflect.DeepEqual(res, test.res) {
+			t.Errorf("unexpected result: want %v, got %v", test.res, res)
+		}
+	}
+}

vendor/github.com/prometheus/client_golang/examples/random/main.go

@@ -0,0 +1,103 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// A simple example exposing fictional RPC latencies with different types of
+// random distributions (uniform, normal, and exponential) as Prometheus
+// metrics.
+package main
+
+import (
+	"flag"
+	"math"
+	"math/rand"
+	"net/http"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+var (
+	addr              = flag.String("listen-address", ":8080", "The address to listen on for HTTP requests.")
+	uniformDomain     = flag.Float64("uniform.domain", 200, "The domain for the uniform distribution.")
+	normDomain        = flag.Float64("normal.domain", 200, "The domain for the normal distribution.")
+	normMean          = flag.Float64("normal.mean", 10, "The mean for the normal distribution.")
+	oscillationPeriod = flag.Duration("oscillation-period", 10*time.Minute, "The duration of the rate oscillation period.")
+)
+
+var (
+	// Create a summary to track fictional interservice RPC latencies for three
+	// distinct services with different latency distributions. These services are
+	// differentiated via a "service" label.
+	rpcDurations = prometheus.NewSummaryVec(
+		prometheus.SummaryOpts{
+			Name: "rpc_durations_microseconds",
+			Help: "RPC latency distributions.",
+		},
+		[]string{"service"},
+	)
+	// The same as above, but now as a histogram, and only for the normal
+	// distribution. The buckets are targeted to the parameters of the
+	// normal distribution, with 20 buckets centered on the mean, each
+	// half-sigma wide.
+	rpcDurationsHistogram = prometheus.NewHistogram(prometheus.HistogramOpts{
+		Name:    "rpc_durations_histogram_microseconds",
+		Help:    "RPC latency distributions.",
+		Buckets: prometheus.LinearBuckets(*normMean-5**normDomain, .5**normDomain, 20),
+	})
+)
+
+func init() {
+	// Register the summary and the histogram with Prometheus's default registry.
+	prometheus.MustRegister(rpcDurations)
+	prometheus.MustRegister(rpcDurationsHistogram)
+}
+
+func main() {
+	flag.Parse()
+
+	start := time.Now()
+
+	oscillationFactor := func() float64 {
+		return 2 + math.Sin(math.Sin(2*math.Pi*float64(time.Since(start))/float64(*oscillationPeriod)))
+	}
+
+	// Periodically record some sample latencies for the three services.
+	go func() {
+		for {
+			v := rand.Float64() * *uniformDomain
+			rpcDurations.WithLabelValues("uniform").Observe(v)
+			time.Sleep(time.Duration(100*oscillationFactor()) * time.Millisecond)
+		}
+	}()
+
+	go func() {
+		for {
+			v := (rand.NormFloat64() * *normDomain) + *normMean
+			rpcDurations.WithLabelValues("normal").Observe(v)
+			rpcDurationsHistogram.Observe(v)
+			time.Sleep(time.Duration(75*oscillationFactor()) * time.Millisecond)
+		}
+	}()
+
+	go func() {
+		for {
+			v := rand.ExpFloat64()
+			rpcDurations.WithLabelValues("exponential").Observe(v)
+			time.Sleep(time.Duration(50*oscillationFactor()) * time.Millisecond)
+		}
+	}()
+
+	// Expose the registered metrics via HTTP.
+	http.Handle("/metrics", prometheus.Handler())
+	http.ListenAndServe(*addr, nil)
+}

vendor/github.com/prometheus/client_golang/examples/simple/main.go

@@ -0,0 +1,30 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// A minimal example of how to include Prometheus instrumentation.
+package main
+
+import (
+	"flag"
+	"net/http"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+var addr = flag.String("listen-address", ":8080", "The address to listen on for HTTP requests.")
+
+func main() {
+	flag.Parse()
+	http.Handle("/metrics", prometheus.Handler())
+	http.ListenAndServe(*addr, nil)
+}

vendor/github.com/prometheus/client_golang/prometheus/benchmark_test.go

@@ -0,0 +1,183 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"sync"
+	"testing"
+)
+
+func BenchmarkCounterWithLabelValues(b *testing.B) {
+	m := NewCounterVec(
+		CounterOpts{
+			Name: "benchmark_counter",
+			Help: "A counter to benchmark it.",
+		},
+		[]string{"one", "two", "three"},
+	)
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		m.WithLabelValues("eins", "zwei", "drei").Inc()
+	}
+}
+
+func BenchmarkCounterWithLabelValuesConcurrent(b *testing.B) {
+	m := NewCounterVec(
+		CounterOpts{
+			Name: "benchmark_counter",
+			Help: "A counter to benchmark it.",
+		},
+		[]string{"one", "two", "three"},
+	)
+	b.ReportAllocs()
+	b.ResetTimer()
+	wg := sync.WaitGroup{}
+	for i := 0; i < 10; i++ {
+		wg.Add(1)
+		go func() {
+			for j := 0; j < b.N/10; j++ {
+				m.WithLabelValues("eins", "zwei", "drei").Inc()
+			}
+			wg.Done()
+		}()
+	}
+	wg.Wait()
+}
+
+func BenchmarkCounterWithMappedLabels(b *testing.B) {
+	m := NewCounterVec(
+		CounterOpts{
+			Name: "benchmark_counter",
+			Help: "A counter to benchmark it.",
+		},
+		[]string{"one", "two", "three"},
+	)
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		m.With(Labels{"two": "zwei", "one": "eins", "three": "drei"}).Inc()
+	}
+}
+
+func BenchmarkCounterWithPreparedMappedLabels(b *testing.B) {
+	m := NewCounterVec(
+		CounterOpts{
+			Name: "benchmark_counter",
+			Help: "A counter to benchmark it.",
+		},
+		[]string{"one", "two", "three"},
+	)
+	b.ReportAllocs()
+	b.ResetTimer()
+	labels := Labels{"two": "zwei", "one": "eins", "three": "drei"}
+	for i := 0; i < b.N; i++ {
+		m.With(labels).Inc()
+	}
+}
+
+func BenchmarkCounterNoLabels(b *testing.B) {
+	m := NewCounter(CounterOpts{
+		Name: "benchmark_counter",
+		Help: "A counter to benchmark it.",
+	})
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		m.Inc()
+	}
+}
+
+func BenchmarkGaugeWithLabelValues(b *testing.B) {
+	m := NewGaugeVec(
+		GaugeOpts{
+			Name: "benchmark_gauge",
+			Help: "A gauge to benchmark it.",
+		},
+		[]string{"one", "two", "three"},
+	)
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		m.WithLabelValues("eins", "zwei", "drei").Set(3.1415)
+	}
+}
+
+func BenchmarkGaugeNoLabels(b *testing.B) {
+	m := NewGauge(GaugeOpts{
+		Name: "benchmark_gauge",
+		Help: "A gauge to benchmark it.",
+	})
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		m.Set(3.1415)
+	}
+}
+
+func BenchmarkSummaryWithLabelValues(b *testing.B) {
+	m := NewSummaryVec(
+		SummaryOpts{
+			Name: "benchmark_summary",
+			Help: "A summary to benchmark it.",
+		},
+		[]string{"one", "two", "three"},
+	)
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		m.WithLabelValues("eins", "zwei", "drei").Observe(3.1415)
+	}
+}
+
+func BenchmarkSummaryNoLabels(b *testing.B) {
+	m := NewSummary(SummaryOpts{
+		Name: "benchmark_summary",
+		Help: "A summary to benchmark it.",
+	},
+	)
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		m.Observe(3.1415)
+	}
+}
+
+func BenchmarkHistogramWithLabelValues(b *testing.B) {
+	m := NewHistogramVec(
+		HistogramOpts{
+			Name: "benchmark_histogram",
+			Help: "A histogram to benchmark it.",
+		},
+		[]string{"one", "two", "three"},
+	)
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		m.WithLabelValues("eins", "zwei", "drei").Observe(3.1415)
+	}
+}
+
+func BenchmarkHistogramNoLabels(b *testing.B) {
+	m := NewHistogram(HistogramOpts{
+		Name: "benchmark_histogram",
+		Help: "A histogram to benchmark it.",
+	},
+	)
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		m.Observe(3.1415)
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/counter.go

@@ -30,8 +30,16 @@ type Counter interface {
 	Metric
 	Collector
 
-	// Inc increments the counter by 1. Use Add to increment it by arbitrary
-	// non-negative values.
+	// Set is used to set the Counter to an arbitrary value. It is only used
+	// if you have to transfer a value from an external counter into this
+	// Prometheus metric. Do not use it for regular handling of a
+	// Prometheus counter (as it can be used to break the contract of
+	// monotonically increasing values).
+	//
+	// Deprecated: Use NewConstMetric to create a counter for an external
+	// value. A Counter should never be set.
+	Set(float64)
+	// Inc increments the counter by 1.
 	Inc()
 	// Add adds the given value to the counter. It panics if the value is <
 	// 0.

vendor/github.com/prometheus/client_golang/prometheus/counter_test.go

@@ -0,0 +1,58 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"math"
+	"testing"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+func TestCounterAdd(t *testing.T) {
+	counter := NewCounter(CounterOpts{
+		Name:        "test",
+		Help:        "test help",
+		ConstLabels: Labels{"a": "1", "b": "2"},
+	}).(*counter)
+	counter.Inc()
+	if expected, got := 1., math.Float64frombits(counter.valBits); expected != got {
+		t.Errorf("Expected %f, got %f.", expected, got)
+	}
+	counter.Add(42)
+	if expected, got := 43., math.Float64frombits(counter.valBits); expected != got {
+		t.Errorf("Expected %f, got %f.", expected, got)
+	}
+
+	if expected, got := "counter cannot decrease in value", decreaseCounter(counter).Error(); expected != got {
+		t.Errorf("Expected error %q, got %q.", expected, got)
+	}
+
+	m := &dto.Metric{}
+	counter.Write(m)
+
+	if expected, got := `label:<name:"a" value:"1" > label:<name:"b" value:"2" > counter:<value:43 > `, m.String(); expected != got {
+		t.Errorf("expected %q, got %q", expected, got)
+	}
+}
+
+func decreaseCounter(c *counter) (err error) {
+	defer func() {
+		if e := recover(); e != nil {
+			err = e.(error)
+		}
+	}()
+	c.Add(-1)
+	return nil
+}

vendor/github.com/prometheus/client_golang/prometheus/desc.go

@@ -16,15 +16,20 @@ package prometheus
 import (
 	"errors"
 	"fmt"
+	"regexp"
 	"sort"
 	"strings"
 
 	"github.com/golang/protobuf/proto"
-	"github.com/prometheus/common/model"
 
 	dto "github.com/prometheus/client_model/go"
 )
 
+var (
+	metricNameRE = regexp.MustCompile(`^[a-zA-Z_][a-zA-Z0-9_:]*$`)
+	labelNameRE  = regexp.MustCompile("^[a-zA-Z_][a-zA-Z0-9_]*$")
+)
+
 // reservedLabelPrefix is a prefix which is not legal in user-supplied
 // label names.
 const reservedLabelPrefix = "__"
@@ -73,7 +78,7 @@ type Desc struct {
 	// Help string. Each Desc with the same fqName must have the same
 	// dimHash.
 	dimHash uint64
-	// err is an error that occurred during construction. It is reported on
+	// err is an error that occured during construction. It is reported on
 	// registration time.
 	err error
 }
@@ -98,7 +103,7 @@ func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *
 		d.err = errors.New("empty help string")
 		return d
 	}
-	if !model.IsValidMetricName(model.LabelValue(fqName)) {
+	if !metricNameRE.MatchString(fqName) {
 		d.err = fmt.Errorf("%q is not a valid metric name", fqName)
 		return d
 	}
@@ -195,6 +200,6 @@ func (d *Desc) String() string {
 }
 
 func checkLabelName(l string) bool {
-	return model.LabelName(l).IsValid() &&
+	return labelNameRE.MatchString(l) &&
 		!strings.HasPrefix(l, reservedLabelPrefix)
 }

vendor/github.com/prometheus/client_golang/prometheus/doc.go

@@ -17,7 +17,7 @@
 // Pushgateway (package push).
 //
 // All exported functions and methods are safe to be used concurrently unless
-// specified otherwise.
+//specified otherwise.
 //
 // A Basic Example
 //
@@ -26,7 +26,6 @@
 //    package main
 //
 //    import (
-//    	"log"
 //    	"net/http"
 //
 //    	"github.com/prometheus/client_golang/prometheus"
@@ -60,7 +59,7 @@
 //    	// The Handler function provides a default handler to expose metrics
 //    	// via an HTTP server. "/metrics" is the usual endpoint for that.
 //    	http.Handle("/metrics", promhttp.Handler())
-//      log.Fatal(http.ListenAndServe(":8080", nil))
+//    	http.ListenAndServe(":8080", nil)
 //    }
 //
 //
@@ -70,7 +69,7 @@
 // Metrics
 //
 // The number of exported identifiers in this package might appear a bit
-// overwhelming. However, in addition to the basic plumbing shown in the example
+// overwhelming. Hovever, in addition to the basic plumbing shown in the example
 // above, you only need to understand the different metric types and their
 // vector versions for basic usage.
 //
@@ -96,8 +95,8 @@
 // SummaryVec, HistogramVec, and UntypedVec are not.
 //
 // To create instances of Metrics and their vector versions, you need a suitable
-// …Opts struct, i.e. GaugeOpts, CounterOpts, SummaryOpts, HistogramOpts, or
-// UntypedOpts.
+// …Opts struct, i.e. GaugeOpts, CounterOpts, SummaryOpts,
+// HistogramOpts, or UntypedOpts.
 //
 // Custom Collectors and constant Metrics
 //
@@ -115,8 +114,8 @@
 // Metric instances “on the fly” using NewConstMetric, NewConstHistogram, and
 // NewConstSummary (and their respective Must… versions). That will happen in
 // the Collect method. The Describe method has to return separate Desc
-// instances, representative of the “throw-away” metrics to be created later.
-// NewDesc comes in handy to create those Desc instances.
+// instances, representative of the “throw-away” metrics to be created
+// later. NewDesc comes in handy to create those Desc instances.
 //
 // The Collector example illustrates the use case. You can also look at the
 // source code of the processCollector (mirroring process metrics), the
@@ -130,32 +129,32 @@
 // Advanced Uses of the Registry
 //
 // While MustRegister is the by far most common way of registering a Collector,
-// sometimes you might want to handle the errors the registration might cause.
-// As suggested by the name, MustRegister panics if an error occurs. With the
-// Register function, the error is returned and can be handled.
+// sometimes you might want to handle the errors the registration might
+// cause. As suggested by the name, MustRegister panics if an error occurs. With
+// the Register function, the error is returned and can be handled.
 //
 // An error is returned if the registered Collector is incompatible or
 // inconsistent with already registered metrics. The registry aims for
-// consistency of the collected metrics according to the Prometheus data model.
-// Inconsistencies are ideally detected at registration time, not at collect
-// time. The former will usually be detected at start-up time of a program,
-// while the latter will only happen at scrape time, possibly not even on the
-// first scrape if the inconsistency only becomes relevant later. That is the
-// main reason why a Collector and a Metric have to describe themselves to the
-// registry.
+// consistency of the collected metrics according to the Prometheus data
+// model. Inconsistencies are ideally detected at registration time, not at
+// collect time. The former will usually be detected at start-up time of a
+// program, while the latter will only happen at scrape time, possibly not even
+// on the first scrape if the inconsistency only becomes relevant later. That is
+// the main reason why a Collector and a Metric have to describe themselves to
+// the registry.
 //
 // So far, everything we did operated on the so-called default registry, as it
 // can be found in the global DefaultRegistry variable. With NewRegistry, you
 // can create a custom registry, or you can even implement the Registerer or
-// Gatherer interfaces yourself. The methods Register and Unregister work in the
-// same way on a custom registry as the global functions Register and Unregister
-// on the default registry.
+// Gatherer interfaces yourself. The methods Register and Unregister work in
+// the same way on a custom registry as the global functions Register and
+// Unregister on the default registry.
 //
-// There are a number of uses for custom registries: You can use registries with
-// special properties, see NewPedanticRegistry. You can avoid global state, as
-// it is imposed by the DefaultRegistry. You can use multiple registries at the
-// same time to expose different metrics in different ways. You can use separate
-// registries for testing purposes.
+// There are a number of uses for custom registries: You can use registries
+// with special properties, see NewPedanticRegistry. You can avoid global state,
+// as it is imposed by the DefaultRegistry. You can use multiple registries at
+// the same time to expose different metrics in different ways. You can use
+// separate registries for testing purposes.
 //
 // Also note that the DefaultRegistry comes registered with a Collector for Go
 // runtime metrics (via NewGoCollector) and a Collector for process metrics (via
@@ -167,20 +166,16 @@
 // The Registry implements the Gatherer interface. The caller of the Gather
 // method can then expose the gathered metrics in some way. Usually, the metrics
 // are served via HTTP on the /metrics endpoint. That's happening in the example
-// above. The tools to expose metrics via HTTP are in the promhttp sub-package.
-// (The top-level functions in the prometheus package are deprecated.)
+// above. The tools to expose metrics via HTTP are in the promhttp
+// sub-package. (The top-level functions in the prometheus package are
+// deprecated.)
 //
 // Pushing to the Pushgateway
 //
 // Function for pushing to the Pushgateway can be found in the push sub-package.
 //
-// Graphite Bridge
-//
-// Functions and examples to push metrics from a Gatherer to Graphite can be
-// found in the graphite sub-package.
-//
 // Other Means of Exposition
 //
-// More ways of exposing metrics can easily be added by following the approaches
-// of the existing implementations.
+// More ways of exposing metrics can easily be added. Sending metrics to
+// Graphite would be an example that will soon be implemented.
 package prometheus

vendor/github.com/prometheus/client_golang/prometheus/example_clustermanager_test.go

@@ -0,0 +1,118 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus_test
+
+import "github.com/prometheus/client_golang/prometheus"
+
+// ClusterManager is an example for a system that might have been built without
+// Prometheus in mind. It models a central manager of jobs running in a
+// cluster. To turn it into something that collects Prometheus metrics, we
+// simply add the two methods required for the Collector interface.
+//
+// An additional challenge is that multiple instances of the ClusterManager are
+// run within the same binary, each in charge of a different zone. We need to
+// make use of ConstLabels to be able to register each ClusterManager instance
+// with Prometheus.
+type ClusterManager struct {
+	Zone         string
+	OOMCountDesc *prometheus.Desc
+	RAMUsageDesc *prometheus.Desc
+	// ... many more fields
+}
+
+// ReallyExpensiveAssessmentOfTheSystemState is a mock for the data gathering a
+// real cluster manager would have to do. Since it may actually be really
+// expensive, it must only be called once per collection. This implementation,
+// obviously, only returns some made-up data.
+func (c *ClusterManager) ReallyExpensiveAssessmentOfTheSystemState() (
+	oomCountByHost map[string]int, ramUsageByHost map[string]float64,
+) {
+	// Just example fake data.
+	oomCountByHost = map[string]int{
+		"foo.example.org": 42,
+		"bar.example.org": 2001,
+	}
+	ramUsageByHost = map[string]float64{
+		"foo.example.org": 6.023e23,
+		"bar.example.org": 3.14,
+	}
+	return
+}
+
+// Describe simply sends the two Descs in the struct to the channel.
+func (c *ClusterManager) Describe(ch chan<- *prometheus.Desc) {
+	ch <- c.OOMCountDesc
+	ch <- c.RAMUsageDesc
+}
+
+// Collect first triggers the ReallyExpensiveAssessmentOfTheSystemState. Then it
+// creates constant metrics for each host on the fly based on the returned data.
+//
+// Note that Collect could be called concurrently, so we depend on
+// ReallyExpensiveAssessmentOfTheSystemState to be concurrency-safe.
+func (c *ClusterManager) Collect(ch chan<- prometheus.Metric) {
+	oomCountByHost, ramUsageByHost := c.ReallyExpensiveAssessmentOfTheSystemState()
+	for host, oomCount := range oomCountByHost {
+		ch <- prometheus.MustNewConstMetric(
+			c.OOMCountDesc,
+			prometheus.CounterValue,
+			float64(oomCount),
+			host,
+		)
+	}
+	for host, ramUsage := range ramUsageByHost {
+		ch <- prometheus.MustNewConstMetric(
+			c.RAMUsageDesc,
+			prometheus.GaugeValue,
+			ramUsage,
+			host,
+		)
+	}
+}
+
+// NewClusterManager creates the two Descs OOMCountDesc and RAMUsageDesc. Note
+// that the zone is set as a ConstLabel. (It's different in each instance of the
+// ClusterManager, but constant over the lifetime of an instance.) Then there is
+// a variable label "host", since we want to partition the collected metrics by
+// host. Since all Descs created in this way are consistent across instances,
+// with a guaranteed distinction by the "zone" label, we can register different
+// ClusterManager instances with the same registry.
+func NewClusterManager(zone string) *ClusterManager {
+	return &ClusterManager{
+		Zone: zone,
+		OOMCountDesc: prometheus.NewDesc(
+			"clustermanager_oom_crashes_total",
+			"Number of OOM crashes.",
+			[]string{"host"},
+			prometheus.Labels{"zone": zone},
+		),
+		RAMUsageDesc: prometheus.NewDesc(
+			"clustermanager_ram_usage_bytes",
+			"RAM usage as reported to the cluster manager.",
+			[]string{"host"},
+			prometheus.Labels{"zone": zone},
+		),
+	}
+}
+
+func ExampleCollector() {
+	workerDB := NewClusterManager("db")
+	workerCA := NewClusterManager("ca")
+
+	// Since we are dealing with custom Collector implementations, it might
+	// be a good idea to try it out with a pedantic registry.
+	reg := prometheus.NewPedanticRegistry()
+	reg.MustRegister(workerDB)
+	reg.MustRegister(workerCA)
+}

vendor/github.com/prometheus/client_golang/prometheus/examples_test.go

@@ -0,0 +1,751 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus_test
+
+import (
+	"bytes"
+	"fmt"
+	"math"
+	"net/http"
+	"runtime"
+	"sort"
+	"strings"
+
+	dto "github.com/prometheus/client_model/go"
+	"github.com/prometheus/common/expfmt"
+
+	"github.com/golang/protobuf/proto"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+func ExampleGauge() {
+	opsQueued := prometheus.NewGauge(prometheus.GaugeOpts{
+		Namespace: "our_company",
+		Subsystem: "blob_storage",
+		Name:      "ops_queued",
+		Help:      "Number of blob storage operations waiting to be processed.",
+	})
+	prometheus.MustRegister(opsQueued)
+
+	// 10 operations queued by the goroutine managing incoming requests.
+	opsQueued.Add(10)
+	// A worker goroutine has picked up a waiting operation.
+	opsQueued.Dec()
+	// And once more...
+	opsQueued.Dec()
+}
+
+func ExampleGaugeVec() {
+	opsQueued := prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Namespace: "our_company",
+			Subsystem: "blob_storage",
+			Name:      "ops_queued",
+			Help:      "Number of blob storage operations waiting to be processed, partitioned by user and type.",
+		},
+		[]string{
+			// Which user has requested the operation?
+			"user",
+			// Of what type is the operation?
+			"type",
+		},
+	)
+	prometheus.MustRegister(opsQueued)
+
+	// Increase a value using compact (but order-sensitive!) WithLabelValues().
+	opsQueued.WithLabelValues("bob", "put").Add(4)
+	// Increase a value with a map using WithLabels. More verbose, but order
+	// doesn't matter anymore.
+	opsQueued.With(prometheus.Labels{"type": "delete", "user": "alice"}).Inc()
+}
+
+func ExampleGaugeFunc() {
+	if err := prometheus.Register(prometheus.NewGaugeFunc(
+		prometheus.GaugeOpts{
+			Subsystem: "runtime",
+			Name:      "goroutines_count",
+			Help:      "Number of goroutines that currently exist.",
+		},
+		func() float64 { return float64(runtime.NumGoroutine()) },
+	)); err == nil {
+		fmt.Println("GaugeFunc 'goroutines_count' registered.")
+	}
+	// Note that the count of goroutines is a gauge (and not a counter) as
+	// it can go up and down.
+
+	// Output:
+	// GaugeFunc 'goroutines_count' registered.
+}
+
+func ExampleCounter() {
+	pushCounter := prometheus.NewCounter(prometheus.CounterOpts{
+		Name: "repository_pushes", // Note: No help string...
+	})
+	err := prometheus.Register(pushCounter) // ... so this will return an error.
+	if err != nil {
+		fmt.Println("Push counter couldn't be registered, no counting will happen:", err)
+		return
+	}
+
+	// Try it once more, this time with a help string.
+	pushCounter = prometheus.NewCounter(prometheus.CounterOpts{
+		Name: "repository_pushes",
+		Help: "Number of pushes to external repository.",
+	})
+	err = prometheus.Register(pushCounter)
+	if err != nil {
+		fmt.Println("Push counter couldn't be registered AGAIN, no counting will happen:", err)
+		return
+	}
+
+	pushComplete := make(chan struct{})
+	// TODO: Start a goroutine that performs repository pushes and reports
+	// each completion via the channel.
+	for _ = range pushComplete {
+		pushCounter.Inc()
+	}
+	// Output:
+	// Push counter couldn't be registered, no counting will happen: descriptor Desc{fqName: "repository_pushes", help: "", constLabels: {}, variableLabels: []} is invalid: empty help string
+}
+
+func ExampleCounterVec() {
+	httpReqs := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Name: "http_requests_total",
+			Help: "How many HTTP requests processed, partitioned by status code and HTTP method.",
+		},
+		[]string{"code", "method"},
+	)
+	prometheus.MustRegister(httpReqs)
+
+	httpReqs.WithLabelValues("404", "POST").Add(42)
+
+	// If you have to access the same set of labels very frequently, it
+	// might be good to retrieve the metric only once and keep a handle to
+	// it. But beware of deletion of that metric, see below!
+	m := httpReqs.WithLabelValues("200", "GET")
+	for i := 0; i < 1000000; i++ {
+		m.Inc()
+	}
+	// Delete a metric from the vector. If you have previously kept a handle
+	// to that metric (as above), future updates via that handle will go
+	// unseen (even if you re-create a metric with the same label set
+	// later).
+	httpReqs.DeleteLabelValues("200", "GET")
+	// Same thing with the more verbose Labels syntax.
+	httpReqs.Delete(prometheus.Labels{"method": "GET", "code": "200"})
+}
+
+func ExampleInstrumentHandler() {
+	// Handle the "/doc" endpoint with the standard http.FileServer handler.
+	// By wrapping the handler with InstrumentHandler, request count,
+	// request and response sizes, and request latency are automatically
+	// exported to Prometheus, partitioned by HTTP status code and method
+	// and by the handler name (here "fileserver").
+	http.Handle("/doc", prometheus.InstrumentHandler(
+		"fileserver", http.FileServer(http.Dir("/usr/share/doc")),
+	))
+	// The Prometheus handler still has to be registered to handle the
+	// "/metrics" endpoint. The handler returned by prometheus.Handler() is
+	// already instrumented - with "prometheus" as the handler name. In this
+	// example, we want the handler name to be "metrics", so we instrument
+	// the uninstrumented Prometheus handler ourselves.
+	http.Handle("/metrics", prometheus.InstrumentHandler(
+		"metrics", prometheus.UninstrumentedHandler(),
+	))
+}
+
+func ExampleLabelPairSorter() {
+	labelPairs := []*dto.LabelPair{
+		&dto.LabelPair{Name: proto.String("status"), Value: proto.String("404")},
+		&dto.LabelPair{Name: proto.String("method"), Value: proto.String("get")},
+	}
+
+	sort.Sort(prometheus.LabelPairSorter(labelPairs))
+
+	fmt.Println(labelPairs)
+	// Output:
+	// [name:"method" value:"get"  name:"status" value:"404" ]
+}
+
+func ExampleRegister() {
+	// Imagine you have a worker pool and want to count the tasks completed.
+	taskCounter := prometheus.NewCounter(prometheus.CounterOpts{
+		Subsystem: "worker_pool",
+		Name:      "completed_tasks_total",
+		Help:      "Total number of tasks completed.",
+	})
+	// This will register fine.
+	if err := prometheus.Register(taskCounter); err != nil {
+		fmt.Println(err)
+	} else {
+		fmt.Println("taskCounter registered.")
+	}
+	// Don't forget to tell the HTTP server about the Prometheus handler.
+	// (In a real program, you still need to start the HTTP server...)
+	http.Handle("/metrics", prometheus.Handler())
+
+	// Now you can start workers and give every one of them a pointer to
+	// taskCounter and let it increment it whenever it completes a task.
+	taskCounter.Inc() // This has to happen somewhere in the worker code.
+
+	// But wait, you want to see how individual workers perform. So you need
+	// a vector of counters, with one element for each worker.
+	taskCounterVec := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Subsystem: "worker_pool",
+			Name:      "completed_tasks_total",
+			Help:      "Total number of tasks completed.",
+		},
+		[]string{"worker_id"},
+	)
+
+	// Registering will fail because we already have a metric of that name.
+	if err := prometheus.Register(taskCounterVec); err != nil {
+		fmt.Println("taskCounterVec not registered:", err)
+	} else {
+		fmt.Println("taskCounterVec registered.")
+	}
+
+	// To fix, first unregister the old taskCounter.
+	if prometheus.Unregister(taskCounter) {
+		fmt.Println("taskCounter unregistered.")
+	}
+
+	// Try registering taskCounterVec again.
+	if err := prometheus.Register(taskCounterVec); err != nil {
+		fmt.Println("taskCounterVec not registered:", err)
+	} else {
+		fmt.Println("taskCounterVec registered.")
+	}
+	// Bummer! Still doesn't work.
+
+	// Prometheus will not allow you to ever export metrics with
+	// inconsistent help strings or label names. After unregistering, the
+	// unregistered metrics will cease to show up in the /metrics HTTP
+	// response, but the registry still remembers that those metrics had
+	// been exported before. For this example, we will now choose a
+	// different name. (In a real program, you would obviously not export
+	// the obsolete metric in the first place.)
+	taskCounterVec = prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Subsystem: "worker_pool",
+			Name:      "completed_tasks_by_id",
+			Help:      "Total number of tasks completed.",
+		},
+		[]string{"worker_id"},
+	)
+	if err := prometheus.Register(taskCounterVec); err != nil {
+		fmt.Println("taskCounterVec not registered:", err)
+	} else {
+		fmt.Println("taskCounterVec registered.")
+	}
+	// Finally it worked!
+
+	// The workers have to tell taskCounterVec their id to increment the
+	// right element in the metric vector.
+	taskCounterVec.WithLabelValues("42").Inc() // Code from worker 42.
+
+	// Each worker could also keep a reference to their own counter element
+	// around. Pick the counter at initialization time of the worker.
+	myCounter := taskCounterVec.WithLabelValues("42") // From worker 42 initialization code.
+	myCounter.Inc()                                   // Somewhere in the code of that worker.
+
+	// Note that something like WithLabelValues("42", "spurious arg") would
+	// panic (because you have provided too many label values). If you want
+	// to get an error instead, use GetMetricWithLabelValues(...) instead.
+	notMyCounter, err := taskCounterVec.GetMetricWithLabelValues("42", "spurious arg")
+	if err != nil {
+		fmt.Println("Worker initialization failed:", err)
+	}
+	if notMyCounter == nil {
+		fmt.Println("notMyCounter is nil.")
+	}
+
+	// A different (and somewhat tricky) approach is to use
+	// ConstLabels. ConstLabels are pairs of label names and label values
+	// that never change. You might ask what those labels are good for (and
+	// rightfully so - if they never change, they could as well be part of
+	// the metric name). There are essentially two use-cases: The first is
+	// if labels are constant throughout the lifetime of a binary execution,
+	// but they vary over time or between different instances of a running
+	// binary. The second is what we have here: Each worker creates and
+	// registers an own Counter instance where the only difference is in the
+	// value of the ConstLabels. Those Counters can all be registered
+	// because the different ConstLabel values guarantee that each worker
+	// will increment a different Counter metric.
+	counterOpts := prometheus.CounterOpts{
+		Subsystem:   "worker_pool",
+		Name:        "completed_tasks",
+		Help:        "Total number of tasks completed.",
+		ConstLabels: prometheus.Labels{"worker_id": "42"},
+	}
+	taskCounterForWorker42 := prometheus.NewCounter(counterOpts)
+	if err := prometheus.Register(taskCounterForWorker42); err != nil {
+		fmt.Println("taskCounterVForWorker42 not registered:", err)
+	} else {
+		fmt.Println("taskCounterForWorker42 registered.")
+	}
+	// Obviously, in real code, taskCounterForWorker42 would be a member
+	// variable of a worker struct, and the "42" would be retrieved with a
+	// GetId() method or something. The Counter would be created and
+	// registered in the initialization code of the worker.
+
+	// For the creation of the next Counter, we can recycle
+	// counterOpts. Just change the ConstLabels.
+	counterOpts.ConstLabels = prometheus.Labels{"worker_id": "2001"}
+	taskCounterForWorker2001 := prometheus.NewCounter(counterOpts)
+	if err := prometheus.Register(taskCounterForWorker2001); err != nil {
+		fmt.Println("taskCounterVForWorker2001 not registered:", err)
+	} else {
+		fmt.Println("taskCounterForWorker2001 registered.")
+	}
+
+	taskCounterForWorker2001.Inc()
+	taskCounterForWorker42.Inc()
+	taskCounterForWorker2001.Inc()
+
+	// Yet another approach would be to turn the workers themselves into
+	// Collectors and register them. See the Collector example for details.
+
+	// Output:
+	// taskCounter registered.
+	// taskCounterVec not registered: a previously registered descriptor with the same fully-qualified name as Desc{fqName: "worker_pool_completed_tasks_total", help: "Total number of tasks completed.", constLabels: {}, variableLabels: [worker_id]} has different label names or a different help string
+	// taskCounter unregistered.
+	// taskCounterVec not registered: a previously registered descriptor with the same fully-qualified name as Desc{fqName: "worker_pool_completed_tasks_total", help: "Total number of tasks completed.", constLabels: {}, variableLabels: [worker_id]} has different label names or a different help string
+	// taskCounterVec registered.
+	// Worker initialization failed: inconsistent label cardinality
+	// notMyCounter is nil.
+	// taskCounterForWorker42 registered.
+	// taskCounterForWorker2001 registered.
+}
+
+func ExampleSummary() {
+	temps := prometheus.NewSummary(prometheus.SummaryOpts{
+		Name: "pond_temperature_celsius",
+		Help: "The temperature of the frog pond.", // Sorry, we can't measure how badly it smells.
+	})
+
+	// Simulate some observations.
+	for i := 0; i < 1000; i++ {
+		temps.Observe(30 + math.Floor(120*math.Sin(float64(i)*0.1))/10)
+	}
+
+	// Just for demonstration, let's check the state of the summary by
+	// (ab)using its Write method (which is usually only used by Prometheus
+	// internally).
+	metric := &dto.Metric{}
+	temps.Write(metric)
+	fmt.Println(proto.MarshalTextString(metric))
+
+	// Output:
+	// summary: <
+	//   sample_count: 1000
+	//   sample_sum: 29969.50000000001
+	//   quantile: <
+	//     quantile: 0.5
+	//     value: 31.1
+	//   >
+	//   quantile: <
+	//     quantile: 0.9
+	//     value: 41.3
+	//   >
+	//   quantile: <
+	//     quantile: 0.99
+	//     value: 41.9
+	//   >
+	// >
+}
+
+func ExampleSummaryVec() {
+	temps := prometheus.NewSummaryVec(
+		prometheus.SummaryOpts{
+			Name: "pond_temperature_celsius",
+			Help: "The temperature of the frog pond.", // Sorry, we can't measure how badly it smells.
+		},
+		[]string{"species"},
+	)
+
+	// Simulate some observations.
+	for i := 0; i < 1000; i++ {
+		temps.WithLabelValues("litoria-caerulea").Observe(30 + math.Floor(120*math.Sin(float64(i)*0.1))/10)
+		temps.WithLabelValues("lithobates-catesbeianus").Observe(32 + math.Floor(100*math.Cos(float64(i)*0.11))/10)
+	}
+
+	// Create a Summary without any observations.
+	temps.WithLabelValues("leiopelma-hochstetteri")
+
+	// Just for demonstration, let's check the state of the summary vector
+	// by registering it with a custom registry and then let it collect the
+	// metrics.
+	reg := prometheus.NewRegistry()
+	reg.MustRegister(temps)
+
+	metricFamilies, err := reg.Gather()
+	if err != nil || len(metricFamilies) != 1 {
+		panic("unexpected behavior of custom test registry")
+	}
+	fmt.Println(proto.MarshalTextString(metricFamilies[0]))
+
+	// Output:
+	// name: "pond_temperature_celsius"
+	// help: "The temperature of the frog pond."
+	// type: SUMMARY
+	// metric: <
+	//   label: <
+	//     name: "species"
+	//     value: "leiopelma-hochstetteri"
+	//   >
+	//   summary: <
+	//     sample_count: 0
+	//     sample_sum: 0
+	//     quantile: <
+	//       quantile: 0.5
+	//       value: nan
+	//     >
+	//     quantile: <
+	//       quantile: 0.9
+	//       value: nan
+	//     >
+	//     quantile: <
+	//       quantile: 0.99
+	//       value: nan
+	//     >
+	//   >
+	// >
+	// metric: <
+	//   label: <
+	//     name: "species"
+	//     value: "lithobates-catesbeianus"
+	//   >
+	//   summary: <
+	//     sample_count: 1000
+	//     sample_sum: 31956.100000000017
+	//     quantile: <
+	//       quantile: 0.5
+	//       value: 32.4
+	//     >
+	//     quantile: <
+	//       quantile: 0.9
+	//       value: 41.4
+	//     >
+	//     quantile: <
+	//       quantile: 0.99
+	//       value: 41.9
+	//     >
+	//   >
+	// >
+	// metric: <
+	//   label: <
+	//     name: "species"
+	//     value: "litoria-caerulea"
+	//   >
+	//   summary: <
+	//     sample_count: 1000
+	//     sample_sum: 29969.50000000001
+	//     quantile: <
+	//       quantile: 0.5
+	//       value: 31.1
+	//     >
+	//     quantile: <
+	//       quantile: 0.9
+	//       value: 41.3
+	//     >
+	//     quantile: <
+	//       quantile: 0.99
+	//       value: 41.9
+	//     >
+	//   >
+	// >
+}
+
+func ExampleNewConstSummary() {
+	desc := prometheus.NewDesc(
+		"http_request_duration_seconds",
+		"A summary of the HTTP request durations.",
+		[]string{"code", "method"},
+		prometheus.Labels{"owner": "example"},
+	)
+
+	// Create a constant summary from values we got from a 3rd party telemetry system.
+	s := prometheus.MustNewConstSummary(
+		desc,
+		4711, 403.34,
+		map[float64]float64{0.5: 42.3, 0.9: 323.3},
+		"200", "get",
+	)
+
+	// Just for demonstration, let's check the state of the summary by
+	// (ab)using its Write method (which is usually only used by Prometheus
+	// internally).
+	metric := &dto.Metric{}
+	s.Write(metric)
+	fmt.Println(proto.MarshalTextString(metric))
+
+	// Output:
+	// label: <
+	//   name: "code"
+	//   value: "200"
+	// >
+	// label: <
+	//   name: "method"
+	//   value: "get"
+	// >
+	// label: <
+	//   name: "owner"
+	//   value: "example"
+	// >
+	// summary: <
+	//   sample_count: 4711
+	//   sample_sum: 403.34
+	//   quantile: <
+	//     quantile: 0.5
+	//     value: 42.3
+	//   >
+	//   quantile: <
+	//     quantile: 0.9
+	//     value: 323.3
+	//   >
+	// >
+}
+
+func ExampleHistogram() {
+	temps := prometheus.NewHistogram(prometheus.HistogramOpts{
+		Name:    "pond_temperature_celsius",
+		Help:    "The temperature of the frog pond.", // Sorry, we can't measure how badly it smells.
+		Buckets: prometheus.LinearBuckets(20, 5, 5),  // 5 buckets, each 5 centigrade wide.
+	})
+
+	// Simulate some observations.
+	for i := 0; i < 1000; i++ {
+		temps.Observe(30 + math.Floor(120*math.Sin(float64(i)*0.1))/10)
+	}
+
+	// Just for demonstration, let's check the state of the histogram by
+	// (ab)using its Write method (which is usually only used by Prometheus
+	// internally).
+	metric := &dto.Metric{}
+	temps.Write(metric)
+	fmt.Println(proto.MarshalTextString(metric))
+
+	// Output:
+	// histogram: <
+	//   sample_count: 1000
+	//   sample_sum: 29969.50000000001
+	//   bucket: <
+	//     cumulative_count: 192
+	//     upper_bound: 20
+	//   >
+	//   bucket: <
+	//     cumulative_count: 366
+	//     upper_bound: 25
+	//   >
+	//   bucket: <
+	//     cumulative_count: 501
+	//     upper_bound: 30
+	//   >
+	//   bucket: <
+	//     cumulative_count: 638
+	//     upper_bound: 35
+	//   >
+	//   bucket: <
+	//     cumulative_count: 816
+	//     upper_bound: 40
+	//   >
+	// >
+}
+
+func ExampleNewConstHistogram() {
+	desc := prometheus.NewDesc(
+		"http_request_duration_seconds",
+		"A histogram of the HTTP request durations.",
+		[]string{"code", "method"},
+		prometheus.Labels{"owner": "example"},
+	)
+
+	// Create a constant histogram from values we got from a 3rd party telemetry system.
+	h := prometheus.MustNewConstHistogram(
+		desc,
+		4711, 403.34,
+		map[float64]uint64{25: 121, 50: 2403, 100: 3221, 200: 4233},
+		"200", "get",
+	)
+
+	// Just for demonstration, let's check the state of the histogram by
+	// (ab)using its Write method (which is usually only used by Prometheus
+	// internally).
+	metric := &dto.Metric{}
+	h.Write(metric)
+	fmt.Println(proto.MarshalTextString(metric))
+
+	// Output:
+	// label: <
+	//   name: "code"
+	//   value: "200"
+	// >
+	// label: <
+	//   name: "method"
+	//   value: "get"
+	// >
+	// label: <
+	//   name: "owner"
+	//   value: "example"
+	// >
+	// histogram: <
+	//   sample_count: 4711
+	//   sample_sum: 403.34
+	//   bucket: <
+	//     cumulative_count: 121
+	//     upper_bound: 25
+	//   >
+	//   bucket: <
+	//     cumulative_count: 2403
+	//     upper_bound: 50
+	//   >
+	//   bucket: <
+	//     cumulative_count: 3221
+	//     upper_bound: 100
+	//   >
+	//   bucket: <
+	//     cumulative_count: 4233
+	//     upper_bound: 200
+	//   >
+	// >
+}
+
+func ExampleAlreadyRegisteredError() {
+	reqCounter := prometheus.NewCounter(prometheus.CounterOpts{
+		Name: "requests_total",
+		Help: "The total number of requests served.",
+	})
+	if err := prometheus.Register(reqCounter); err != nil {
+		if are, ok := err.(prometheus.AlreadyRegisteredError); ok {
+			// A counter for that metric has been registered before.
+			// Use the old counter from now on.
+			reqCounter = are.ExistingCollector.(prometheus.Counter)
+		} else {
+			// Something else went wrong!
+			panic(err)
+		}
+	}
+}
+
+func ExampleGatherers() {
+	reg := prometheus.NewRegistry()
+	temp := prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "temperature_kelvin",
+			Help: "Temperature in Kelvin.",
+		},
+		[]string{"location"},
+	)
+	reg.MustRegister(temp)
+	temp.WithLabelValues("outside").Set(273.14)
+	temp.WithLabelValues("inside").Set(298.44)
+
+	var parser expfmt.TextParser
+
+	text := `
+# TYPE humidity_percent gauge
+# HELP humidity_percent Humidity in %.
+humidity_percent{location="outside"} 45.4
+humidity_percent{location="inside"} 33.2
+# TYPE temperature_kelvin gauge
+# HELP temperature_kelvin Temperature in Kelvin.
+temperature_kelvin{location="somewhere else"} 4.5
+`
+
+	parseText := func() ([]*dto.MetricFamily, error) {
+		parsed, err := parser.TextToMetricFamilies(strings.NewReader(text))
+		if err != nil {
+			return nil, err
+		}
+		var result []*dto.MetricFamily
+		for _, mf := range parsed {
+			result = append(result, mf)
+		}
+		return result, nil
+	}
+
+	gatherers := prometheus.Gatherers{
+		reg,
+		prometheus.GathererFunc(parseText),
+	}
+
+	gathering, err := gatherers.Gather()
+	if err != nil {
+		fmt.Println(err)
+	}
+
+	out := &bytes.Buffer{}
+	for _, mf := range gathering {
+		if _, err := expfmt.MetricFamilyToText(out, mf); err != nil {
+			panic(err)
+		}
+	}
+	fmt.Print(out.String())
+	fmt.Println("----------")
+
+	// Note how the temperature_kelvin metric family has been merged from
+	// different sources. Now try
+	text = `
+# TYPE humidity_percent gauge
+# HELP humidity_percent Humidity in %.
+humidity_percent{location="outside"} 45.4
+humidity_percent{location="inside"} 33.2
+# TYPE temperature_kelvin gauge
+# HELP temperature_kelvin Temperature in Kelvin.
+# Duplicate metric:
+temperature_kelvin{location="outside"} 265.3
+ # Wrong labels:
+temperature_kelvin 4.5
+`
+
+	gathering, err = gatherers.Gather()
+	if err != nil {
+		fmt.Println(err)
+	}
+	// Note that still as many metrics as possible are returned:
+	out.Reset()
+	for _, mf := range gathering {
+		if _, err := expfmt.MetricFamilyToText(out, mf); err != nil {
+			panic(err)
+		}
+	}
+	fmt.Print(out.String())
+
+	// Output:
+	// # HELP humidity_percent Humidity in %.
+	// # TYPE humidity_percent gauge
+	// humidity_percent{location="inside"} 33.2
+	// humidity_percent{location="outside"} 45.4
+	// # HELP temperature_kelvin Temperature in Kelvin.
+	// # TYPE temperature_kelvin gauge
+	// temperature_kelvin{location="inside"} 298.44
+	// temperature_kelvin{location="outside"} 273.14
+	// temperature_kelvin{location="somewhere else"} 4.5
+	// ----------
+	// 2 error(s) occurred:
+	// * collected metric temperature_kelvin label:<name:"location" value:"outside" > gauge:<value:265.3 >  was collected before with the same name and label values
+	// * collected metric temperature_kelvin gauge:<value:4.5 >  has label dimensions inconsistent with previously collected metrics in the same metric family
+	// # HELP humidity_percent Humidity in %.
+	// # TYPE humidity_percent gauge
+	// humidity_percent{location="inside"} 33.2
+	// humidity_percent{location="outside"} 45.4
+	// # HELP temperature_kelvin Temperature in Kelvin.
+	// # TYPE temperature_kelvin gauge
+	// temperature_kelvin{location="inside"} 298.44
+	// temperature_kelvin{location="outside"} 273.14
+}

vendor/github.com/prometheus/client_golang/prometheus/expvar_collector_test.go

@@ -0,0 +1,97 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus_test
+
+import (
+	"expvar"
+	"fmt"
+	"sort"
+	"strings"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+func ExampleExpvarCollector() {
+	expvarCollector := prometheus.NewExpvarCollector(map[string]*prometheus.Desc{
+		"memstats": prometheus.NewDesc(
+			"expvar_memstats",
+			"All numeric memstats as one metric family. Not a good role-model, actually... ;-)",
+			[]string{"type"}, nil,
+		),
+		"lone-int": prometheus.NewDesc(
+			"expvar_lone_int",
+			"Just an expvar int as an example.",
+			nil, nil,
+		),
+		"http-request-map": prometheus.NewDesc(
+			"expvar_http_request_total",
+			"How many http requests processed, partitioned by status code and http method.",
+			[]string{"code", "method"}, nil,
+		),
+	})
+	prometheus.MustRegister(expvarCollector)
+
+	// The Prometheus part is done here. But to show that this example is
+	// doing anything, we have to manually export something via expvar.  In
+	// real-life use-cases, some library would already have exported via
+	// expvar what we want to re-export as Prometheus metrics.
+	expvar.NewInt("lone-int").Set(42)
+	expvarMap := expvar.NewMap("http-request-map")
+	var (
+		expvarMap1, expvarMap2                             expvar.Map
+		expvarInt11, expvarInt12, expvarInt21, expvarInt22 expvar.Int
+	)
+	expvarMap1.Init()
+	expvarMap2.Init()
+	expvarInt11.Set(3)
+	expvarInt12.Set(13)
+	expvarInt21.Set(11)
+	expvarInt22.Set(212)
+	expvarMap1.Set("POST", &expvarInt11)
+	expvarMap1.Set("GET", &expvarInt12)
+	expvarMap2.Set("POST", &expvarInt21)
+	expvarMap2.Set("GET", &expvarInt22)
+	expvarMap.Set("404", &expvarMap1)
+	expvarMap.Set("200", &expvarMap2)
+	// Results in the following expvar map:
+	// "http-request-count": {"200": {"POST": 11, "GET": 212}, "404": {"POST": 3, "GET": 13}}
+
+	// Let's see what the scrape would yield, but exclude the memstats metrics.
+	metricStrings := []string{}
+	metric := dto.Metric{}
+	metricChan := make(chan prometheus.Metric)
+	go func() {
+		expvarCollector.Collect(metricChan)
+		close(metricChan)
+	}()
+	for m := range metricChan {
+		if strings.Index(m.Desc().String(), "expvar_memstats") == -1 {
+			metric.Reset()
+			m.Write(&metric)
+			metricStrings = append(metricStrings, metric.String())
+		}
+	}
+	sort.Strings(metricStrings)
+	for _, s := range metricStrings {
+		fmt.Println(strings.TrimRight(s, " "))
+	}
+	// Output:
+	// label:<name:"code" value:"200" > label:<name:"method" value:"GET" > untyped:<value:212 >
+	// label:<name:"code" value:"200" > label:<name:"method" value:"POST" > untyped:<value:11 >
+	// label:<name:"code" value:"404" > label:<name:"method" value:"GET" > untyped:<value:13 >
+	// label:<name:"code" value:"404" > label:<name:"method" value:"POST" > untyped:<value:3 >
+	// untyped:<value:42 >
+}

vendor/github.com/prometheus/client_golang/prometheus/gauge.go

@@ -27,21 +27,16 @@ type Gauge interface {
 
 	// Set sets the Gauge to an arbitrary value.
 	Set(float64)
-	// Inc increments the Gauge by 1. Use Add to increment it by arbitrary
-	// values.
+	// Inc increments the Gauge by 1.
 	Inc()
-	// Dec decrements the Gauge by 1. Use Sub to decrement it by arbitrary
-	// values.
+	// Dec decrements the Gauge by 1.
 	Dec()
-	// Add adds the given value to the Gauge. (The value can be negative,
-	// resulting in a decrease of the Gauge.)
+	// Add adds the given value to the Gauge. (The value can be
+	// negative, resulting in a decrease of the Gauge.)
 	Add(float64)
 	// Sub subtracts the given value from the Gauge. (The value can be
 	// negative, resulting in an increase of the Gauge.)
 	Sub(float64)
-
-	// SetToCurrentTime sets the Gauge to the current Unix time in seconds.
-	SetToCurrentTime()
 }
 
 // GaugeOpts is an alias for Opts. See there for doc comments.

vendor/github.com/prometheus/client_golang/prometheus/gauge_test.go

@@ -0,0 +1,182 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"math"
+	"math/rand"
+	"sync"
+	"testing"
+	"testing/quick"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+func listenGaugeStream(vals, result chan float64, done chan struct{}) {
+	var sum float64
+outer:
+	for {
+		select {
+		case <-done:
+			close(vals)
+			for v := range vals {
+				sum += v
+			}
+			break outer
+		case v := <-vals:
+			sum += v
+		}
+	}
+	result <- sum
+	close(result)
+}
+
+func TestGaugeConcurrency(t *testing.T) {
+	it := func(n uint32) bool {
+		mutations := int(n % 10000)
+		concLevel := int(n%15 + 1)
+
+		var start, end sync.WaitGroup
+		start.Add(1)
+		end.Add(concLevel)
+
+		sStream := make(chan float64, mutations*concLevel)
+		result := make(chan float64)
+		done := make(chan struct{})
+
+		go listenGaugeStream(sStream, result, done)
+		go func() {
+			end.Wait()
+			close(done)
+		}()
+
+		gge := NewGauge(GaugeOpts{
+			Name: "test_gauge",
+			Help: "no help can be found here",
+		})
+		for i := 0; i < concLevel; i++ {
+			vals := make([]float64, mutations)
+			for j := 0; j < mutations; j++ {
+				vals[j] = rand.Float64() - 0.5
+			}
+
+			go func(vals []float64) {
+				start.Wait()
+				for _, v := range vals {
+					sStream <- v
+					gge.Add(v)
+				}
+				end.Done()
+			}(vals)
+		}
+		start.Done()
+
+		if expected, got := <-result, math.Float64frombits(gge.(*value).valBits); math.Abs(expected-got) > 0.000001 {
+			t.Fatalf("expected approx. %f, got %f", expected, got)
+			return false
+		}
+		return true
+	}
+
+	if err := quick.Check(it, nil); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestGaugeVecConcurrency(t *testing.T) {
+	it := func(n uint32) bool {
+		mutations := int(n % 10000)
+		concLevel := int(n%15 + 1)
+		vecLength := int(n%5 + 1)
+
+		var start, end sync.WaitGroup
+		start.Add(1)
+		end.Add(concLevel)
+
+		sStreams := make([]chan float64, vecLength)
+		results := make([]chan float64, vecLength)
+		done := make(chan struct{})
+
+		for i := 0; i < vecLength; i++ {
+			sStreams[i] = make(chan float64, mutations*concLevel)
+			results[i] = make(chan float64)
+			go listenGaugeStream(sStreams[i], results[i], done)
+		}
+
+		go func() {
+			end.Wait()
+			close(done)
+		}()
+
+		gge := NewGaugeVec(
+			GaugeOpts{
+				Name: "test_gauge",
+				Help: "no help can be found here",
+			},
+			[]string{"label"},
+		)
+		for i := 0; i < concLevel; i++ {
+			vals := make([]float64, mutations)
+			pick := make([]int, mutations)
+			for j := 0; j < mutations; j++ {
+				vals[j] = rand.Float64() - 0.5
+				pick[j] = rand.Intn(vecLength)
+			}
+
+			go func(vals []float64) {
+				start.Wait()
+				for i, v := range vals {
+					sStreams[pick[i]] <- v
+					gge.WithLabelValues(string('A' + pick[i])).Add(v)
+				}
+				end.Done()
+			}(vals)
+		}
+		start.Done()
+
+		for i := range sStreams {
+			if expected, got := <-results[i], math.Float64frombits(gge.WithLabelValues(string('A'+i)).(*value).valBits); math.Abs(expected-got) > 0.000001 {
+				t.Fatalf("expected approx. %f, got %f", expected, got)
+				return false
+			}
+		}
+		return true
+	}
+
+	if err := quick.Check(it, nil); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestGaugeFunc(t *testing.T) {
+	gf := NewGaugeFunc(
+		GaugeOpts{
+			Name:        "test_name",
+			Help:        "test help",
+			ConstLabels: Labels{"a": "1", "b": "2"},
+		},
+		func() float64 { return 3.1415 },
+	)
+
+	if expected, got := `Desc{fqName: "test_name", help: "test help", constLabels: {a="1",b="2"}, variableLabels: []}`, gf.Desc().String(); expected != got {
+		t.Errorf("expected %q, got %q", expected, got)
+	}
+
+	m := &dto.Metric{}
+	gf.Write(m)
+
+	if expected, got := `label:<name:"a" value:"1" > label:<name:"b" value:"2" > gauge:<value:3.1415 > `, m.String(); expected != got {
+		t.Errorf("expected %q, got %q", expected, got)
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/go_collector.go

@@ -8,9 +8,8 @@ import (
 )
 
 type goCollector struct {
-	goroutinesDesc *Desc
-	threadsDesc    *Desc
-	gcDesc         *Desc
+	goroutines Gauge
+	gcDesc     *Desc
 
 	// metrics to describe and collect
 	metrics memStatsMetrics
@@ -20,14 +19,11 @@ type goCollector struct {
 // go process.
 func NewGoCollector() Collector {
 	return &goCollector{
-		goroutinesDesc: NewDesc(
-			"go_goroutines",
-			"Number of goroutines that currently exist.",
-			nil, nil),
-		threadsDesc: NewDesc(
-			"go_threads",
-			"Number of OS threads created",
-			nil, nil),
+		goroutines: NewGauge(GaugeOpts{
+			Namespace: "go",
+			Name:      "goroutines",
+			Help:      "Number of goroutines that currently exist.",
+		}),
 		gcDesc: NewDesc(
 			"go_gc_duration_seconds",
 			"A summary of the GC invocation durations.",
@@ -52,7 +48,7 @@ func NewGoCollector() Collector {
 			}, {
 				desc: NewDesc(
 					memstatNamespace("sys_bytes"),
-					"Number of bytes obtained from system.",
+					"Number of bytes obtained by system. Sum of all system allocations.",
 					nil, nil,
 				),
 				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Sys) },
@@ -115,12 +111,12 @@ func NewGoCollector() Collector {
 				valType: GaugeValue,
 			}, {
 				desc: NewDesc(
-					memstatNamespace("heap_released_bytes"),
-					"Number of heap bytes released to OS.",
+					memstatNamespace("heap_released_bytes_total"),
+					"Total number of heap bytes released to OS.",
 					nil, nil,
 				),
 				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapReleased) },
-				valType: GaugeValue,
+				valType: CounterValue,
 			}, {
 				desc: NewDesc(
 					memstatNamespace("heap_objects"),
@@ -217,14 +213,6 @@ func NewGoCollector() Collector {
 				),
 				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.LastGC) / 1e9 },
 				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("gc_cpu_fraction"),
-					"The fraction of this program's available CPU time used by the GC since the program started.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return ms.GCCPUFraction },
-				valType: GaugeValue,
 			},
 		},
 	}
@@ -236,9 +224,9 @@ func memstatNamespace(s string) string {
 
 // Describe returns all descriptions of the collector.
 func (c *goCollector) Describe(ch chan<- *Desc) {
-	ch <- c.goroutinesDesc
-	ch <- c.threadsDesc
+	ch <- c.goroutines.Desc()
 	ch <- c.gcDesc
+
 	for _, i := range c.metrics {
 		ch <- i.desc
 	}
@@ -246,9 +234,8 @@ func (c *goCollector) Describe(ch chan<- *Desc) {
 
 // Collect returns the current state of all metrics of the collector.
 func (c *goCollector) Collect(ch chan<- Metric) {
-	ch <- MustNewConstMetric(c.goroutinesDesc, GaugeValue, float64(runtime.NumGoroutine()))
-	n, _ := runtime.ThreadCreateProfile(nil)
-	ch <- MustNewConstMetric(c.threadsDesc, GaugeValue, float64(n))
+	c.goroutines.Set(float64(runtime.NumGoroutine()))
+	ch <- c.goroutines
 
 	var stats debug.GCStats
 	stats.PauseQuantiles = make([]time.Duration, 5)

vendor/github.com/prometheus/client_golang/prometheus/go_collector_test.go

@@ -0,0 +1,123 @@
+package prometheus
+
+import (
+	"runtime"
+	"testing"
+	"time"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+func TestGoCollector(t *testing.T) {
+	var (
+		c      = NewGoCollector()
+		ch     = make(chan Metric)
+		waitc  = make(chan struct{})
+		closec = make(chan struct{})
+		old    = -1
+	)
+	defer close(closec)
+
+	go func() {
+		c.Collect(ch)
+		go func(c <-chan struct{}) {
+			<-c
+		}(closec)
+		<-waitc
+		c.Collect(ch)
+	}()
+
+	for {
+		select {
+		case metric := <-ch:
+			switch m := metric.(type) {
+			// Attention, this also catches Counter...
+			case Gauge:
+				pb := &dto.Metric{}
+				m.Write(pb)
+				if pb.GetGauge() == nil {
+					continue
+				}
+
+				if old == -1 {
+					old = int(pb.GetGauge().GetValue())
+					close(waitc)
+					continue
+				}
+
+				if diff := int(pb.GetGauge().GetValue()) - old; diff != 1 {
+					// TODO: This is flaky in highly concurrent situations.
+					t.Errorf("want 1 new goroutine, got %d", diff)
+				}
+
+				// GoCollector performs two sends per call.
+				// On line 27 we need to receive the second send
+				// to shut down cleanly.
+				<-ch
+				return
+			}
+		case <-time.After(1 * time.Second):
+			t.Fatalf("expected collect timed out")
+		}
+	}
+}
+
+func TestGCCollector(t *testing.T) {
+	var (
+		c        = NewGoCollector()
+		ch       = make(chan Metric)
+		waitc    = make(chan struct{})
+		closec   = make(chan struct{})
+		oldGC    uint64
+		oldPause float64
+	)
+	defer close(closec)
+
+	go func() {
+		c.Collect(ch)
+		// force GC
+		runtime.GC()
+		<-waitc
+		c.Collect(ch)
+	}()
+
+	first := true
+	for {
+		select {
+		case metric := <-ch:
+			switch m := metric.(type) {
+			case *constSummary, *value:
+				pb := &dto.Metric{}
+				m.Write(pb)
+				if pb.GetSummary() == nil {
+					continue
+				}
+
+				if len(pb.GetSummary().Quantile) != 5 {
+					t.Errorf("expected 4 buckets, got %d", len(pb.GetSummary().Quantile))
+				}
+				for idx, want := range []float64{0.0, 0.25, 0.5, 0.75, 1.0} {
+					if *pb.GetSummary().Quantile[idx].Quantile != want {
+						t.Errorf("bucket #%d is off, got %f, want %f", idx, *pb.GetSummary().Quantile[idx].Quantile, want)
+					}
+				}
+				if first {
+					first = false
+					oldGC = *pb.GetSummary().SampleCount
+					oldPause = *pb.GetSummary().SampleSum
+					close(waitc)
+					continue
+				}
+				if diff := *pb.GetSummary().SampleCount - oldGC; diff != 1 {
+					t.Errorf("want 1 new garbage collection run, got %d", diff)
+				}
+				if diff := *pb.GetSummary().SampleSum - oldPause; diff <= 0 {
+					t.Errorf("want moar pause, got %f", diff)
+				}
+				return
+			}
+		case <-time.After(1 * time.Second):
+			t.Fatalf("expected collect timed out")
+		}
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/histogram.go

@@ -308,23 +308,23 @@ func NewHistogramVec(opts HistogramOpts, labelNames []string) *HistogramVec {
 }
 
 // GetMetricWithLabelValues replaces the method of the same name in
-// MetricVec. The difference is that this method returns an Observer and not a
-// Metric so that no type conversion to an Observer is required.
-func (m *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) {
+// MetricVec. The difference is that this method returns a Histogram and not a
+// Metric so that no type conversion is required.
+func (m *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Histogram, error) {
 	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
 	if metric != nil {
-		return metric.(Observer), err
+		return metric.(Histogram), err
 	}
 	return nil, err
 }
 
 // GetMetricWith replaces the method of the same name in MetricVec. The
-// difference is that this method returns an Observer and not a Metric so that no
-// type conversion to an Observer is required.
-func (m *HistogramVec) GetMetricWith(labels Labels) (Observer, error) {
+// difference is that this method returns a Histogram and not a Metric so that no
+// type conversion is required.
+func (m *HistogramVec) GetMetricWith(labels Labels) (Histogram, error) {
 	metric, err := m.MetricVec.GetMetricWith(labels)
 	if metric != nil {
-		return metric.(Observer), err
+		return metric.(Histogram), err
 	}
 	return nil, err
 }
@@ -333,15 +333,15 @@ func (m *HistogramVec) GetMetricWith(labels Labels) (Observer, error) {
 // GetMetricWithLabelValues would have returned an error. By not returning an
 // error, WithLabelValues allows shortcuts like
 //     myVec.WithLabelValues("404", "GET").Observe(42.21)
-func (m *HistogramVec) WithLabelValues(lvs ...string) Observer {
-	return m.MetricVec.WithLabelValues(lvs...).(Observer)
+func (m *HistogramVec) WithLabelValues(lvs ...string) Histogram {
+	return m.MetricVec.WithLabelValues(lvs...).(Histogram)
 }
 
 // With works as GetMetricWith, but panics where GetMetricWithLabels would have
 // returned an error. By not returning an error, With allows shortcuts like
 //     myVec.With(Labels{"code": "404", "method": "GET"}).Observe(42.21)
-func (m *HistogramVec) With(labels Labels) Observer {
-	return m.MetricVec.With(labels).(Observer)
+func (m *HistogramVec) With(labels Labels) Histogram {
+	return m.MetricVec.With(labels).(Histogram)
 }
 
 type constHistogram struct {

vendor/github.com/prometheus/client_golang/prometheus/histogram_test.go

@@ -0,0 +1,326 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"math"
+	"math/rand"
+	"reflect"
+	"sort"
+	"sync"
+	"testing"
+	"testing/quick"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+func benchmarkHistogramObserve(w int, b *testing.B) {
+	b.StopTimer()
+
+	wg := new(sync.WaitGroup)
+	wg.Add(w)
+
+	g := new(sync.WaitGroup)
+	g.Add(1)
+
+	s := NewHistogram(HistogramOpts{})
+
+	for i := 0; i < w; i++ {
+		go func() {
+			g.Wait()
+
+			for i := 0; i < b.N; i++ {
+				s.Observe(float64(i))
+			}
+
+			wg.Done()
+		}()
+	}
+
+	b.StartTimer()
+	g.Done()
+	wg.Wait()
+}
+
+func BenchmarkHistogramObserve1(b *testing.B) {
+	benchmarkHistogramObserve(1, b)
+}
+
+func BenchmarkHistogramObserve2(b *testing.B) {
+	benchmarkHistogramObserve(2, b)
+}
+
+func BenchmarkHistogramObserve4(b *testing.B) {
+	benchmarkHistogramObserve(4, b)
+}
+
+func BenchmarkHistogramObserve8(b *testing.B) {
+	benchmarkHistogramObserve(8, b)
+}
+
+func benchmarkHistogramWrite(w int, b *testing.B) {
+	b.StopTimer()
+
+	wg := new(sync.WaitGroup)
+	wg.Add(w)
+
+	g := new(sync.WaitGroup)
+	g.Add(1)
+
+	s := NewHistogram(HistogramOpts{})
+
+	for i := 0; i < 1000000; i++ {
+		s.Observe(float64(i))
+	}
+
+	for j := 0; j < w; j++ {
+		outs := make([]dto.Metric, b.N)
+
+		go func(o []dto.Metric) {
+			g.Wait()
+
+			for i := 0; i < b.N; i++ {
+				s.Write(&o[i])
+			}
+
+			wg.Done()
+		}(outs)
+	}
+
+	b.StartTimer()
+	g.Done()
+	wg.Wait()
+}
+
+func BenchmarkHistogramWrite1(b *testing.B) {
+	benchmarkHistogramWrite(1, b)
+}
+
+func BenchmarkHistogramWrite2(b *testing.B) {
+	benchmarkHistogramWrite(2, b)
+}
+
+func BenchmarkHistogramWrite4(b *testing.B) {
+	benchmarkHistogramWrite(4, b)
+}
+
+func BenchmarkHistogramWrite8(b *testing.B) {
+	benchmarkHistogramWrite(8, b)
+}
+
+// Intentionally adding +Inf here to test if that case is handled correctly.
+// Also, getCumulativeCounts depends on it.
+var testBuckets = []float64{-2, -1, -0.5, 0, 0.5, 1, 2, math.Inf(+1)}
+
+func TestHistogramConcurrency(t *testing.T) {
+	if testing.Short() {
+		t.Skip("Skipping test in short mode.")
+	}
+
+	rand.Seed(42)
+
+	it := func(n uint32) bool {
+		mutations := int(n%1e4 + 1e4)
+		concLevel := int(n%5 + 1)
+		total := mutations * concLevel
+
+		var start, end sync.WaitGroup
+		start.Add(1)
+		end.Add(concLevel)
+
+		sum := NewHistogram(HistogramOpts{
+			Name:    "test_histogram",
+			Help:    "helpless",
+			Buckets: testBuckets,
+		})
+
+		allVars := make([]float64, total)
+		var sampleSum float64
+		for i := 0; i < concLevel; i++ {
+			vals := make([]float64, mutations)
+			for j := 0; j < mutations; j++ {
+				v := rand.NormFloat64()
+				vals[j] = v
+				allVars[i*mutations+j] = v
+				sampleSum += v
+			}
+
+			go func(vals []float64) {
+				start.Wait()
+				for _, v := range vals {
+					sum.Observe(v)
+				}
+				end.Done()
+			}(vals)
+		}
+		sort.Float64s(allVars)
+		start.Done()
+		end.Wait()
+
+		m := &dto.Metric{}
+		sum.Write(m)
+		if got, want := int(*m.Histogram.SampleCount), total; got != want {
+			t.Errorf("got sample count %d, want %d", got, want)
+		}
+		if got, want := *m.Histogram.SampleSum, sampleSum; math.Abs((got-want)/want) > 0.001 {
+			t.Errorf("got sample sum %f, want %f", got, want)
+		}
+
+		wantCounts := getCumulativeCounts(allVars)
+
+		if got, want := len(m.Histogram.Bucket), len(testBuckets)-1; got != want {
+			t.Errorf("got %d buckets in protobuf, want %d", got, want)
+		}
+		for i, wantBound := range testBuckets {
+			if i == len(testBuckets)-1 {
+				break // No +Inf bucket in protobuf.
+			}
+			if gotBound := *m.Histogram.Bucket[i].UpperBound; gotBound != wantBound {
+				t.Errorf("got bound %f, want %f", gotBound, wantBound)
+			}
+			if gotCount, wantCount := *m.Histogram.Bucket[i].CumulativeCount, wantCounts[i]; gotCount != wantCount {
+				t.Errorf("got count %d, want %d", gotCount, wantCount)
+			}
+		}
+		return true
+	}
+
+	if err := quick.Check(it, nil); err != nil {
+		t.Error(err)
+	}
+}
+
+func TestHistogramVecConcurrency(t *testing.T) {
+	if testing.Short() {
+		t.Skip("Skipping test in short mode.")
+	}
+
+	rand.Seed(42)
+
+	objectives := make([]float64, 0, len(DefObjectives))
+	for qu := range DefObjectives {
+
+		objectives = append(objectives, qu)
+	}
+	sort.Float64s(objectives)
+
+	it := func(n uint32) bool {
+		mutations := int(n%1e4 + 1e4)
+		concLevel := int(n%7 + 1)
+		vecLength := int(n%3 + 1)
+
+		var start, end sync.WaitGroup
+		start.Add(1)
+		end.Add(concLevel)
+
+		his := NewHistogramVec(
+			HistogramOpts{
+				Name:    "test_histogram",
+				Help:    "helpless",
+				Buckets: []float64{-2, -1, -0.5, 0, 0.5, 1, 2, math.Inf(+1)},
+			},
+			[]string{"label"},
+		)
+
+		allVars := make([][]float64, vecLength)
+		sampleSums := make([]float64, vecLength)
+		for i := 0; i < concLevel; i++ {
+			vals := make([]float64, mutations)
+			picks := make([]int, mutations)
+			for j := 0; j < mutations; j++ {
+				v := rand.NormFloat64()
+				vals[j] = v
+				pick := rand.Intn(vecLength)
+				picks[j] = pick
+				allVars[pick] = append(allVars[pick], v)
+				sampleSums[pick] += v
+			}
+
+			go func(vals []float64) {
+				start.Wait()
+				for i, v := range vals {
+					his.WithLabelValues(string('A' + picks[i])).Observe(v)
+				}
+				end.Done()
+			}(vals)
+		}
+		for _, vars := range allVars {
+			sort.Float64s(vars)
+		}
+		start.Done()
+		end.Wait()
+
+		for i := 0; i < vecLength; i++ {
+			m := &dto.Metric{}
+			s := his.WithLabelValues(string('A' + i))
+			s.Write(m)
+
+			if got, want := len(m.Histogram.Bucket), len(testBuckets)-1; got != want {
+				t.Errorf("got %d buckets in protobuf, want %d", got, want)
+			}
+			if got, want := int(*m.Histogram.SampleCount), len(allVars[i]); got != want {
+				t.Errorf("got sample count %d, want %d", got, want)
+			}
+			if got, want := *m.Histogram.SampleSum, sampleSums[i]; math.Abs((got-want)/want) > 0.001 {
+				t.Errorf("got sample sum %f, want %f", got, want)
+			}
+
+			wantCounts := getCumulativeCounts(allVars[i])
+
+			for j, wantBound := range testBuckets {
+				if j == len(testBuckets)-1 {
+					break // No +Inf bucket in protobuf.
+				}
+				if gotBound := *m.Histogram.Bucket[j].UpperBound; gotBound != wantBound {
+					t.Errorf("got bound %f, want %f", gotBound, wantBound)
+				}
+				if gotCount, wantCount := *m.Histogram.Bucket[j].CumulativeCount, wantCounts[j]; gotCount != wantCount {
+					t.Errorf("got count %d, want %d", gotCount, wantCount)
+				}
+			}
+		}
+		return true
+	}
+
+	if err := quick.Check(it, nil); err != nil {
+		t.Error(err)
+	}
+}
+
+func getCumulativeCounts(vars []float64) []uint64 {
+	counts := make([]uint64, len(testBuckets))
+	for _, v := range vars {
+		for i := len(testBuckets) - 1; i >= 0; i-- {
+			if v > testBuckets[i] {
+				break
+			}
+			counts[i]++
+		}
+	}
+	return counts
+}
+
+func TestBuckets(t *testing.T) {
+	got := LinearBuckets(-15, 5, 6)
+	want := []float64{-15, -10, -5, 0, 5, 10}
+	if !reflect.DeepEqual(got, want) {
+		t.Errorf("linear buckets: got %v, want %v", got, want)
+	}
+
+	got = ExponentialBuckets(100, 1.2, 3)
+	want = []float64{100, 120, 144}
+	if !reflect.DeepEqual(got, want) {
+		t.Errorf("linear buckets: got %v, want %v", got, want)
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/http.go

@@ -62,8 +62,7 @@ func giveBuf(buf *bytes.Buffer) {
 //
 // Deprecated: Please note the issues described in the doc comment of
 // InstrumentHandler. You might want to consider using promhttp.Handler instead
-// (which is not instrumented, but can be instrumented with the tooling provided
-// in package promhttp).
+// (which is non instrumented).
 func Handler() http.Handler {
 	return InstrumentHandler("prometheus", UninstrumentedHandler())
 }
@@ -159,8 +158,7 @@ func nowSeries(t ...time.Time) nower {
 // value. http_requests_total is a metric vector partitioned by HTTP method
 // (label name "method") and HTTP status code (label name "code").
 //
-// Deprecated: InstrumentHandler has several issues. Use the tooling provided in
-// package promhttp instead. The issues are the following:
+// Deprecated: InstrumentHandler has several issues:
 //
 // - It uses Summaries rather than Histograms. Summaries are not useful if
 // aggregation across multiple instances is required.
@@ -174,8 +172,9 @@ func nowSeries(t ...time.Time) nower {
 // httputil.ReverseProxy is a prominent example for a handler
 // performing such writes.
 //
-// - It has additional issues with HTTP/2, cf.
-// https://github.com/prometheus/client_golang/issues/272.
+// Upcoming versions of this package will provide ways of instrumenting HTTP
+// handlers that are more flexible and have fewer issues. Please prefer direct
+// instrumentation in the meantime.
 func InstrumentHandler(handlerName string, handler http.Handler) http.HandlerFunc {
 	return InstrumentHandlerFunc(handlerName, handler.ServeHTTP)
 }
@@ -185,13 +184,12 @@ func InstrumentHandler(handlerName string, handler http.Handler) http.HandlerFun
 // issues).
 //
 // Deprecated: InstrumentHandlerFunc is deprecated for the same reasons as
-// InstrumentHandler is. Use the tooling provided in package promhttp instead.
+// InstrumentHandler is.
 func InstrumentHandlerFunc(handlerName string, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
 	return InstrumentHandlerFuncWithOpts(
 		SummaryOpts{
 			Subsystem:   "http",
 			ConstLabels: Labels{"handler": handlerName},
-			Objectives:  map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001},
 		},
 		handlerFunc,
 	)
@@ -224,7 +222,7 @@ func InstrumentHandlerFunc(handlerName string, handlerFunc func(http.ResponseWri
 // SummaryOpts.
 //
 // Deprecated: InstrumentHandlerWithOpts is deprecated for the same reasons as
-// InstrumentHandler is. Use the tooling provided in package promhttp instead.
+// InstrumentHandler is.
 func InstrumentHandlerWithOpts(opts SummaryOpts, handler http.Handler) http.HandlerFunc {
 	return InstrumentHandlerFuncWithOpts(opts, handler.ServeHTTP)
 }
@@ -235,7 +233,7 @@ func InstrumentHandlerWithOpts(opts SummaryOpts, handler http.Handler) http.Hand
 // SummaryOpts are used.
 //
 // Deprecated: InstrumentHandlerFuncWithOpts is deprecated for the same reasons
-// as InstrumentHandler is. Use the tooling provided in package promhttp instead.
+// as InstrumentHandler is.
 func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
 	reqCnt := NewCounterVec(
 		CounterOpts{
@@ -247,52 +245,34 @@ func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.Respo
 		},
 		instLabels,
 	)
-	if err := Register(reqCnt); err != nil {
-		if are, ok := err.(AlreadyRegisteredError); ok {
-			reqCnt = are.ExistingCollector.(*CounterVec)
-		} else {
-			panic(err)
-		}
-	}
 
 	opts.Name = "request_duration_microseconds"
 	opts.Help = "The HTTP request latencies in microseconds."
 	reqDur := NewSummary(opts)
-	if err := Register(reqDur); err != nil {
-		if are, ok := err.(AlreadyRegisteredError); ok {
-			reqDur = are.ExistingCollector.(Summary)
-		} else {
-			panic(err)
-		}
-	}
 
 	opts.Name = "request_size_bytes"
 	opts.Help = "The HTTP request sizes in bytes."
 	reqSz := NewSummary(opts)
-	if err := Register(reqSz); err != nil {
-		if are, ok := err.(AlreadyRegisteredError); ok {
-			reqSz = are.ExistingCollector.(Summary)
-		} else {
-			panic(err)
-		}
-	}
 
 	opts.Name = "response_size_bytes"
 	opts.Help = "The HTTP response sizes in bytes."
 	resSz := NewSummary(opts)
-	if err := Register(resSz); err != nil {
-		if are, ok := err.(AlreadyRegisteredError); ok {
-			resSz = are.ExistingCollector.(Summary)
-		} else {
-			panic(err)
-		}
-	}
+
+	regReqCnt := MustRegisterOrGet(reqCnt).(*CounterVec)
+	regReqDur := MustRegisterOrGet(reqDur).(Summary)
+	regReqSz := MustRegisterOrGet(reqSz).(Summary)
+	regResSz := MustRegisterOrGet(resSz).(Summary)
 
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		now := time.Now()
 
 		delegate := &responseWriterDelegator{ResponseWriter: w}
-		out := computeApproximateRequestSize(r)
+		out := make(chan int)
+		urlLen := 0
+		if r.URL != nil {
+			urlLen = len(r.URL.String())
+		}
+		go computeApproximateRequestSize(r, out, urlLen)
 
 		_, cn := w.(http.CloseNotifier)
 		_, fl := w.(http.Flusher)
@@ -310,44 +290,30 @@ func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.Respo
 
 		method := sanitizeMethod(r.Method)
 		code := sanitizeCode(delegate.status)
-		reqCnt.WithLabelValues(method, code).Inc()
-		reqDur.Observe(elapsed)
-		resSz.Observe(float64(delegate.written))
-		reqSz.Observe(float64(<-out))
+		regReqCnt.WithLabelValues(method, code).Inc()
+		regReqDur.Observe(elapsed)
+		regResSz.Observe(float64(delegate.written))
+		regReqSz.Observe(float64(<-out))
 	})
 }
 
-func computeApproximateRequestSize(r *http.Request) <-chan int {
-	// Get URL length in current go routine for avoiding a race condition.
-	// HandlerFunc that runs in parallel may modify the URL.
-	s := 0
-	if r.URL != nil {
-		s += len(r.URL.String())
+func computeApproximateRequestSize(r *http.Request, out chan int, s int) {
+	s += len(r.Method)
+	s += len(r.Proto)
+	for name, values := range r.Header {
+		s += len(name)
+		for _, value := range values {
+			s += len(value)
+		}
 	}
+	s += len(r.Host)
 
-	out := make(chan int, 1)
+	// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
 
-	go func() {
-		s += len(r.Method)
-		s += len(r.Proto)
-		for name, values := range r.Header {
-			s += len(name)
-			for _, value := range values {
-				s += len(value)
-			}
-		}
-		s += len(r.Host)
-
-		// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
-
-		if r.ContentLength != -1 {
-			s += int(r.ContentLength)
-		}
-		out <- s
-		close(out)
-	}()
-
-	return out
+	if r.ContentLength != -1 {
+		s += int(r.ContentLength)
+	}
+	out <- s
 }
 
 type responseWriterDelegator struct {

vendor/github.com/prometheus/client_golang/prometheus/http_test.go

@@ -0,0 +1,121 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+type respBody string
+
+func (b respBody) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	w.WriteHeader(http.StatusTeapot)
+	w.Write([]byte(b))
+}
+
+func TestInstrumentHandler(t *testing.T) {
+	defer func(n nower) {
+		now = n.(nower)
+	}(now)
+
+	instant := time.Now()
+	end := instant.Add(30 * time.Second)
+	now = nowSeries(instant, end)
+	respBody := respBody("Howdy there!")
+
+	hndlr := InstrumentHandler("test-handler", respBody)
+
+	opts := SummaryOpts{
+		Subsystem:   "http",
+		ConstLabels: Labels{"handler": "test-handler"},
+	}
+
+	reqCnt := MustRegisterOrGet(NewCounterVec(
+		CounterOpts{
+			Namespace:   opts.Namespace,
+			Subsystem:   opts.Subsystem,
+			Name:        "requests_total",
+			Help:        "Total number of HTTP requests made.",
+			ConstLabels: opts.ConstLabels,
+		},
+		instLabels,
+	)).(*CounterVec)
+
+	opts.Name = "request_duration_microseconds"
+	opts.Help = "The HTTP request latencies in microseconds."
+	reqDur := MustRegisterOrGet(NewSummary(opts)).(Summary)
+
+	opts.Name = "request_size_bytes"
+	opts.Help = "The HTTP request sizes in bytes."
+	MustRegisterOrGet(NewSummary(opts))
+
+	opts.Name = "response_size_bytes"
+	opts.Help = "The HTTP response sizes in bytes."
+	MustRegisterOrGet(NewSummary(opts))
+
+	reqCnt.Reset()
+
+	resp := httptest.NewRecorder()
+	req := &http.Request{
+		Method: "GET",
+	}
+
+	hndlr.ServeHTTP(resp, req)
+
+	if resp.Code != http.StatusTeapot {
+		t.Fatalf("expected status %d, got %d", http.StatusTeapot, resp.Code)
+	}
+	if string(resp.Body.Bytes()) != "Howdy there!" {
+		t.Fatalf("expected body %s, got %s", "Howdy there!", string(resp.Body.Bytes()))
+	}
+
+	out := &dto.Metric{}
+	reqDur.Write(out)
+	if want, got := "test-handler", out.Label[0].GetValue(); want != got {
+		t.Errorf("want label value %q in reqDur, got %q", want, got)
+	}
+	if want, got := uint64(1), out.Summary.GetSampleCount(); want != got {
+		t.Errorf("want sample count %d in reqDur, got %d", want, got)
+	}
+
+	out.Reset()
+	if want, got := 1, len(reqCnt.children); want != got {
+		t.Errorf("want %d children in reqCnt, got %d", want, got)
+	}
+	cnt, err := reqCnt.GetMetricWithLabelValues("get", "418")
+	if err != nil {
+		t.Fatal(err)
+	}
+	cnt.Write(out)
+	if want, got := "418", out.Label[0].GetValue(); want != got {
+		t.Errorf("want label value %q in reqCnt, got %q", want, got)
+	}
+	if want, got := "test-handler", out.Label[1].GetValue(); want != got {
+		t.Errorf("want label value %q in reqCnt, got %q", want, got)
+	}
+	if want, got := "get", out.Label[2].GetValue(); want != got {
+		t.Errorf("want label value %q in reqCnt, got %q", want, got)
+	}
+	if out.Counter == nil {
+		t.Fatal("expected non-nil counter in reqCnt")
+	}
+	if want, got := 1., out.Counter.GetValue(); want != got {
+		t.Errorf("want reqCnt of %f, got %f", want, got)
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/metric_test.go

@@ -0,0 +1,35 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import "testing"
+
+func TestBuildFQName(t *testing.T) {
+	scenarios := []struct{ namespace, subsystem, name, result string }{
+		{"a", "b", "c", "a_b_c"},
+		{"", "b", "c", "b_c"},
+		{"a", "", "c", "a_c"},
+		{"", "", "c", "c"},
+		{"a", "b", "", ""},
+		{"a", "", "", ""},
+		{"", "b", "", ""},
+		{" ", "", "", ""},
+	}
+
+	for i, s := range scenarios {
+		if want, got := s.result, BuildFQName(s.namespace, s.subsystem, s.name); want != got {
+			t.Errorf("%d. want %s, got %s", i, want, got)
+		}
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/observer.go

@@ -1,50 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-// Observer is the interface that wraps the Observe method, which is used by
-// Histogram and Summary to add observations.
-type Observer interface {
-	Observe(float64)
-}
-
-// The ObserverFunc type is an adapter to allow the use of ordinary
-// functions as Observers. If f is a function with the appropriate
-// signature, ObserverFunc(f) is an Observer that calls f.
-//
-// This adapter is usually used in connection with the Timer type, and there are
-// two general use cases:
-//
-// The most common one is to use a Gauge as the Observer for a Timer.
-// See the "Gauge" Timer example.
-//
-// The more advanced use case is to create a function that dynamically decides
-// which Observer to use for observing the duration. See the "Complex" Timer
-// example.
-type ObserverFunc func(float64)
-
-// Observe calls f(value). It implements Observer.
-func (f ObserverFunc) Observe(value float64) {
-	f(value)
-}
-
-// ObserverVec is an interface implemented by `HistogramVec` and `SummaryVec`.
-type ObserverVec interface {
-	GetMetricWith(Labels) (Observer, error)
-	GetMetricWithLabelValues(lvs ...string) (Observer, error)
-	With(Labels) Observer
-	WithLabelValues(...string) Observer
-
-	Collector
-}

vendor/github.com/prometheus/client_golang/prometheus/process_collector.go

@@ -19,10 +19,10 @@ type processCollector struct {
 	pid             int
 	collectFn       func(chan<- Metric)
 	pidFn           func() (int, error)
-	cpuTotal        *Desc
-	openFDs, maxFDs *Desc
-	vsize, rss      *Desc
-	startTime       *Desc
+	cpuTotal        Counter
+	openFDs, maxFDs Gauge
+	vsize, rss      Gauge
+	startTime       Gauge
 }
 
 // NewProcessCollector returns a collector which exports the current state of
@@ -44,45 +44,40 @@ func NewProcessCollectorPIDFn(
 	pidFn func() (int, error),
 	namespace string,
 ) Collector {
-	ns := ""
-	if len(namespace) > 0 {
-		ns = namespace + "_"
-	}
-
 	c := processCollector{
 		pidFn:     pidFn,
 		collectFn: func(chan<- Metric) {},
 
-		cpuTotal: NewDesc(
-			ns+"process_cpu_seconds_total",
-			"Total user and system CPU time spent in seconds.",
-			nil, nil,
-		),
-		openFDs: NewDesc(
-			ns+"process_open_fds",
-			"Number of open file descriptors.",
-			nil, nil,
-		),
-		maxFDs: NewDesc(
-			ns+"process_max_fds",
-			"Maximum number of open file descriptors.",
-			nil, nil,
-		),
-		vsize: NewDesc(
-			ns+"process_virtual_memory_bytes",
-			"Virtual memory size in bytes.",
-			nil, nil,
-		),
-		rss: NewDesc(
-			ns+"process_resident_memory_bytes",
-			"Resident memory size in bytes.",
-			nil, nil,
-		),
-		startTime: NewDesc(
-			ns+"process_start_time_seconds",
-			"Start time of the process since unix epoch in seconds.",
-			nil, nil,
-		),
+		cpuTotal: NewCounter(CounterOpts{
+			Namespace: namespace,
+			Name:      "process_cpu_seconds_total",
+			Help:      "Total user and system CPU time spent in seconds.",
+		}),
+		openFDs: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_open_fds",
+			Help:      "Number of open file descriptors.",
+		}),
+		maxFDs: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_max_fds",
+			Help:      "Maximum number of open file descriptors.",
+		}),
+		vsize: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_virtual_memory_bytes",
+			Help:      "Virtual memory size in bytes.",
+		}),
+		rss: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_resident_memory_bytes",
+			Help:      "Resident memory size in bytes.",
+		}),
+		startTime: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_start_time_seconds",
+			Help:      "Start time of the process since unix epoch in seconds.",
+		}),
 	}
 
 	// Set up process metric collection if supported by the runtime.
@@ -95,12 +90,12 @@ func NewProcessCollectorPIDFn(
 
 // Describe returns all descriptions of the collector.
 func (c *processCollector) Describe(ch chan<- *Desc) {
-	ch <- c.cpuTotal
-	ch <- c.openFDs
-	ch <- c.maxFDs
-	ch <- c.vsize
-	ch <- c.rss
-	ch <- c.startTime
+	ch <- c.cpuTotal.Desc()
+	ch <- c.openFDs.Desc()
+	ch <- c.maxFDs.Desc()
+	ch <- c.vsize.Desc()
+	ch <- c.rss.Desc()
+	ch <- c.startTime.Desc()
 }
 
 // Collect returns the current state of all metrics of the collector.
@@ -122,19 +117,26 @@ func (c *processCollector) processCollect(ch chan<- Metric) {
 	}
 
 	if stat, err := p.NewStat(); err == nil {
-		ch <- MustNewConstMetric(c.cpuTotal, CounterValue, stat.CPUTime())
-		ch <- MustNewConstMetric(c.vsize, GaugeValue, float64(stat.VirtualMemory()))
-		ch <- MustNewConstMetric(c.rss, GaugeValue, float64(stat.ResidentMemory()))
+		c.cpuTotal.Set(stat.CPUTime())
+		ch <- c.cpuTotal
+		c.vsize.Set(float64(stat.VirtualMemory()))
+		ch <- c.vsize
+		c.rss.Set(float64(stat.ResidentMemory()))
+		ch <- c.rss
+
 		if startTime, err := stat.StartTime(); err == nil {
-			ch <- MustNewConstMetric(c.startTime, GaugeValue, startTime)
+			c.startTime.Set(startTime)
+			ch <- c.startTime
 		}
 	}
 
 	if fds, err := p.FileDescriptorsLen(); err == nil {
-		ch <- MustNewConstMetric(c.openFDs, GaugeValue, float64(fds))
+		c.openFDs.Set(float64(fds))
+		ch <- c.openFDs
 	}
 
 	if limits, err := p.NewLimits(); err == nil {
-		ch <- MustNewConstMetric(c.maxFDs, GaugeValue, float64(limits.OpenFiles))
+		c.maxFDs.Set(float64(limits.OpenFiles))
+		ch <- c.maxFDs
 	}
 }

vendor/github.com/prometheus/client_golang/prometheus/process_collector_test.go

@@ -0,0 +1,58 @@
+package prometheus
+
+import (
+	"bytes"
+	"os"
+	"regexp"
+	"testing"
+
+	"github.com/prometheus/common/expfmt"
+	"github.com/prometheus/procfs"
+)
+
+func TestProcessCollector(t *testing.T) {
+	if _, err := procfs.Self(); err != nil {
+		t.Skipf("skipping TestProcessCollector, procfs not available: %s", err)
+	}
+
+	registry := NewRegistry()
+	if err := registry.Register(NewProcessCollector(os.Getpid(), "")); err != nil {
+		t.Fatal(err)
+	}
+	if err := registry.Register(NewProcessCollectorPIDFn(
+		func() (int, error) { return os.Getpid(), nil }, "foobar"),
+	); err != nil {
+		t.Fatal(err)
+	}
+
+	mfs, err := registry.Gather()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var buf bytes.Buffer
+	for _, mf := range mfs {
+		if _, err := expfmt.MetricFamilyToText(&buf, mf); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	for _, re := range []*regexp.Regexp{
+		regexp.MustCompile("process_cpu_seconds_total [0-9]"),
+		regexp.MustCompile("process_max_fds [1-9]"),
+		regexp.MustCompile("process_open_fds [1-9]"),
+		regexp.MustCompile("process_virtual_memory_bytes [1-9]"),
+		regexp.MustCompile("process_resident_memory_bytes [1-9]"),
+		regexp.MustCompile("process_start_time_seconds [0-9.]{10,}"),
+		regexp.MustCompile("foobar_process_cpu_seconds_total [0-9]"),
+		regexp.MustCompile("foobar_process_max_fds [1-9]"),
+		regexp.MustCompile("foobar_process_open_fds [1-9]"),
+		regexp.MustCompile("foobar_process_virtual_memory_bytes [1-9]"),
+		regexp.MustCompile("foobar_process_resident_memory_bytes [1-9]"),
+		regexp.MustCompile("foobar_process_start_time_seconds [0-9.]{10,}"),
+	} {
+		if !re.Match(buf.Bytes()) {
+			t.Errorf("want body to match %s\n%s", re, buf.String())
+		}
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_1_8.go

@@ -1,73 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build go1.8
-
-package promhttp
-
-import (
-	"io"
-	"net/http"
-)
-
-// newDelegator handles the four different methods of upgrading a
-// http.ResponseWriter to delegator.
-func newDelegator(w http.ResponseWriter, observeWriteHeaderFunc func(int)) delegator {
-	d := &responseWriterDelegator{
-		ResponseWriter:     w,
-		observeWriteHeader: observeWriteHeaderFunc,
-	}
-
-	_, cn := w.(http.CloseNotifier)
-	_, fl := w.(http.Flusher)
-	_, hj := w.(http.Hijacker)
-	_, ps := w.(http.Pusher)
-	_, rf := w.(io.ReaderFrom)
-
-	// Check for the four most common combination of interfaces a
-	// http.ResponseWriter might implement.
-	switch {
-	case cn && fl && hj && rf && ps:
-		// All interfaces.
-		return &fancyPushDelegator{
-			fancyDelegator: &fancyDelegator{d},
-			p:              &pushDelegator{d},
-		}
-	case cn && fl && hj && rf:
-		// All interfaces, except http.Pusher.
-		return &fancyDelegator{d}
-	case ps:
-		// Just http.Pusher.
-		return &pushDelegator{d}
-	}
-
-	return d
-}
-
-type fancyPushDelegator struct {
-	p *pushDelegator
-
-	*fancyDelegator
-}
-
-func (f *fancyPushDelegator) Push(target string, opts *http.PushOptions) error {
-	return f.p.Push(target, opts)
-}
-
-type pushDelegator struct {
-	*responseWriterDelegator
-}
-
-func (f *pushDelegator) Push(target string, opts *http.PushOptions) error {
-	return f.ResponseWriter.(http.Pusher).Push(target, opts)
-}

vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go

@@ -11,24 +11,21 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// Package promhttp provides tooling around HTTP servers and clients.
+// Copyright (c) 2013, The Prometheus Authors
+// All rights reserved.
 //
-// First, the package allows the creation of http.Handler instances to expose
-// Prometheus metrics via HTTP. promhttp.Handler acts on the
-// prometheus.DefaultGatherer. With HandlerFor, you can create a handler for a
-// custom registry or anything that implements the Gatherer interface. It also
-// allows the creation of handlers that act differently on errors or allow to
-// log errors.
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+// Package promhttp contains functions to create http.Handler instances to
+// expose Prometheus metrics via HTTP. In later versions of this package, it
+// will also contain tooling to instrument instances of http.Handler and
+// http.RoundTripper.
 //
-// Second, the package provides tooling to instrument instances of http.Handler
-// via middleware. Middleware wrappers follow the naming scheme
-// InstrumentHandlerX, where X describes the intended use of the middleware.
-// See each function's doc comment for specific details.
-//
-// Finally, the package allows for an http.RoundTripper to be instrumented via
-// middleware. Middleware wrappers follow the naming scheme
-// InstrumentRoundTripperX, where X describes the intended use of the
-// middleware. See each function's doc comment for specific details.
+// promhttp.Handler acts on the prometheus.DefaultGatherer. With HandlerFor,
+// you can create a handler for a custom registry or anything that implements
+// the Gatherer interface. It also allows to create handlers that act
+// differently on errors or allow to log errors.
 package promhttp
 
 import (

vendor/github.com/prometheus/client_golang/prometheus/promhttp/http_test.go

@@ -0,0 +1,137 @@
+// Copyright 2016 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Copyright (c) 2013, The Prometheus Authors
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+package promhttp
+
+import (
+	"bytes"
+	"errors"
+	"log"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+type errorCollector struct{}
+
+func (e errorCollector) Describe(ch chan<- *prometheus.Desc) {
+	ch <- prometheus.NewDesc("invalid_metric", "not helpful", nil, nil)
+}
+
+func (e errorCollector) Collect(ch chan<- prometheus.Metric) {
+	ch <- prometheus.NewInvalidMetric(
+		prometheus.NewDesc("invalid_metric", "not helpful", nil, nil),
+		errors.New("collect error"),
+	)
+}
+
+func TestHandlerErrorHandling(t *testing.T) {
+
+	// Create a registry that collects a MetricFamily with two elements,
+	// another with one, and reports an error.
+	reg := prometheus.NewRegistry()
+
+	cnt := prometheus.NewCounter(prometheus.CounterOpts{
+		Name: "the_count",
+		Help: "Ah-ah-ah! Thunder and lightning!",
+	})
+	reg.MustRegister(cnt)
+
+	cntVec := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Name:        "name",
+			Help:        "docstring",
+			ConstLabels: prometheus.Labels{"constname": "constvalue"},
+		},
+		[]string{"labelname"},
+	)
+	cntVec.WithLabelValues("val1").Inc()
+	cntVec.WithLabelValues("val2").Inc()
+	reg.MustRegister(cntVec)
+
+	reg.MustRegister(errorCollector{})
+
+	logBuf := &bytes.Buffer{}
+	logger := log.New(logBuf, "", 0)
+
+	writer := httptest.NewRecorder()
+	request, _ := http.NewRequest("GET", "/", nil)
+	request.Header.Add("Accept", "test/plain")
+
+	errorHandler := HandlerFor(reg, HandlerOpts{
+		ErrorLog:      logger,
+		ErrorHandling: HTTPErrorOnError,
+	})
+	continueHandler := HandlerFor(reg, HandlerOpts{
+		ErrorLog:      logger,
+		ErrorHandling: ContinueOnError,
+	})
+	panicHandler := HandlerFor(reg, HandlerOpts{
+		ErrorLog:      logger,
+		ErrorHandling: PanicOnError,
+	})
+	wantMsg := `error gathering metrics: error collecting metric Desc{fqName: "invalid_metric", help: "not helpful", constLabels: {}, variableLabels: []}: collect error
+`
+	wantErrorBody := `An error has occurred during metrics gathering:
+
+error collecting metric Desc{fqName: "invalid_metric", help: "not helpful", constLabels: {}, variableLabels: []}: collect error
+`
+	wantOKBody := `# HELP name docstring
+# TYPE name counter
+name{constname="constvalue",labelname="val1"} 1
+name{constname="constvalue",labelname="val2"} 1
+# HELP the_count Ah-ah-ah! Thunder and lightning!
+# TYPE the_count counter
+the_count 0
+`
+
+	errorHandler.ServeHTTP(writer, request)
+	if got, want := writer.Code, http.StatusInternalServerError; got != want {
+		t.Errorf("got HTTP status code %d, want %d", got, want)
+	}
+	if got := logBuf.String(); got != wantMsg {
+		t.Errorf("got log message:\n%s\nwant log mesage:\n%s\n", got, wantMsg)
+	}
+	if got := writer.Body.String(); got != wantErrorBody {
+		t.Errorf("got body:\n%s\nwant body:\n%s\n", got, wantErrorBody)
+	}
+	logBuf.Reset()
+	writer.Body.Reset()
+	writer.Code = http.StatusOK
+
+	continueHandler.ServeHTTP(writer, request)
+	if got, want := writer.Code, http.StatusOK; got != want {
+		t.Errorf("got HTTP status code %d, want %d", got, want)
+	}
+	if got := logBuf.String(); got != wantMsg {
+		t.Errorf("got log message %q, want %q", got, wantMsg)
+	}
+	if got := writer.Body.String(); got != wantOKBody {
+		t.Errorf("got body %q, want %q", got, wantOKBody)
+	}
+
+	defer func() {
+		if err := recover(); err == nil {
+			t.Error("expected panic from panicHandler")
+		}
+	}()
+	panicHandler.ServeHTTP(writer, request)
+}

vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go

@@ -1,95 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package promhttp
-
-import (
-	"net/http"
-	"time"
-
-	"github.com/prometheus/client_golang/prometheus"
-)
-
-// The RoundTripperFunc type is an adapter to allow the use of ordinary
-// functions as RoundTrippers. If f is a function with the appropriate
-// signature, RountTripperFunc(f) is a RoundTripper that calls f.
-type RoundTripperFunc func(req *http.Request) (*http.Response, error)
-
-// RoundTrip implements the RoundTripper interface.
-func (rt RoundTripperFunc) RoundTrip(r *http.Request) (*http.Response, error) {
-	return rt(r)
-}
-
-// InstrumentRoundTripperInFlight is a middleware that wraps the provided
-// http.RoundTripper. It sets the provided prometheus.Gauge to the number of
-// requests currently handled by the wrapped http.RoundTripper.
-//
-// See the example for ExampleInstrumentRoundTripperDuration for example usage.
-func InstrumentRoundTripperInFlight(gauge prometheus.Gauge, next http.RoundTripper) RoundTripperFunc {
-	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
-		gauge.Inc()
-		defer gauge.Dec()
-		return next.RoundTrip(r)
-	})
-}
-
-// InstrumentRoundTripperCounter is a middleware that wraps the provided
-// http.RoundTripper to observe the request result with the provided CounterVec.
-// The CounterVec must have zero, one, or two labels. The only allowed label
-// names are "code" and "method". The function panics if any other instance
-// labels are provided. Partitioning of the CounterVec happens by HTTP status
-// code and/or HTTP method if the respective instance label names are present
-// in the CounterVec. For unpartitioned counting, use a CounterVec with
-// zero labels.
-//
-// If the wrapped RoundTripper panics or returns a non-nil error, the Counter
-// is not incremented.
-//
-// See the example for ExampleInstrumentRoundTripperDuration for example usage.
-func InstrumentRoundTripperCounter(counter *prometheus.CounterVec, next http.RoundTripper) RoundTripperFunc {
-	code, method := checkLabels(counter)
-
-	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
-		resp, err := next.RoundTrip(r)
-		if err == nil {
-			counter.With(labels(code, method, r.Method, resp.StatusCode)).Inc()
-		}
-		return resp, err
-	})
-}
-
-// InstrumentRoundTripperDuration is a middleware that wraps the provided
-// http.RoundTripper to observe the request duration with the provided ObserverVec.
-// The ObserverVec must have zero, one, or two labels. The only allowed label
-// names are "code" and "method". The function panics if any other instance
-// labels are provided. The Observe method of the Observer in the ObserverVec
-// is called with the request duration in seconds. Partitioning happens by HTTP
-// status code and/or HTTP method if the respective instance label names are
-// present in the ObserverVec. For unpartitioned observations, use an
-// ObserverVec with zero labels. Note that partitioning of Histograms is
-// expensive and should be used judiciously.
-//
-// If the wrapped RoundTripper panics or returns a non-nil error, no values are
-// reported.
-func InstrumentRoundTripperDuration(obs prometheus.ObserverVec, next http.RoundTripper) RoundTripperFunc {
-	code, method := checkLabels(obs)
-
-	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
-		start := time.Now()
-		resp, err := next.RoundTrip(r)
-		if err == nil {
-			obs.With(labels(code, method, r.Method, resp.StatusCode)).Observe(time.Since(start).Seconds())
-		}
-		return resp, err
-	})
-}

vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client_1_8.go

@@ -1,142 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build go1.8
-
-package promhttp
-
-import (
-	"context"
-	"crypto/tls"
-	"net/http"
-	"net/http/httptrace"
-	"time"
-)
-
-// InstrumentTrace is used to offer flexibility in instrumenting the available
-// httptrace.ClientTrace hook functions. Each function is passed a float64
-// representing the time in seconds since the start of the http request. A user
-// may choose to use separately buckets Histograms, or implement custom
-// instance labels on a per function basis.
-type InstrumentTrace struct {
-	GotConn              func(float64)
-	PutIdleConn          func(float64)
-	GotFirstResponseByte func(float64)
-	Got100Continue       func(float64)
-	DNSStart             func(float64)
-	DNSDone              func(float64)
-	ConnectStart         func(float64)
-	ConnectDone          func(float64)
-	TLSHandshakeStart    func(float64)
-	TLSHandshakeDone     func(float64)
-	WroteHeaders         func(float64)
-	Wait100Continue      func(float64)
-	WroteRequest         func(float64)
-}
-
-// InstrumentRoundTripperTrace is a middleware that wraps the provided
-// RoundTripper and reports times to hook functions provided in the
-// InstrumentTrace struct. Hook functions that are not present in the provided
-// InstrumentTrace struct are ignored. Times reported to the hook functions are
-// time since the start of the request. Note that partitioning of Histograms
-// is expensive and should be used judiciously.
-//
-// For hook functions that receive an error as an argument, no observations are
-// made in the event of a non-nil error value.
-//
-// See the example for ExampleInstrumentRoundTripperDuration for example usage.
-func InstrumentRoundTripperTrace(it *InstrumentTrace, next http.RoundTripper) RoundTripperFunc {
-	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
-		start := time.Now()
-
-		trace := &httptrace.ClientTrace{
-			GotConn: func(_ httptrace.GotConnInfo) {
-				if it.GotConn != nil {
-					it.GotConn(time.Since(start).Seconds())
-				}
-			},
-			PutIdleConn: func(err error) {
-				if err != nil {
-					return
-				}
-				if it.PutIdleConn != nil {
-					it.PutIdleConn(time.Since(start).Seconds())
-				}
-			},
-			DNSStart: func(_ httptrace.DNSStartInfo) {
-				if it.DNSStart != nil {
-					it.DNSStart(time.Since(start).Seconds())
-				}
-			},
-			DNSDone: func(_ httptrace.DNSDoneInfo) {
-				if it.DNSStart != nil {
-					it.DNSStart(time.Since(start).Seconds())
-				}
-			},
-			ConnectStart: func(_, _ string) {
-				if it.ConnectStart != nil {
-					it.ConnectStart(time.Since(start).Seconds())
-				}
-			},
-			ConnectDone: func(_, _ string, err error) {
-				if err != nil {
-					return
-				}
-				if it.ConnectDone != nil {
-					it.ConnectDone(time.Since(start).Seconds())
-				}
-			},
-			GotFirstResponseByte: func() {
-				if it.GotFirstResponseByte != nil {
-					it.GotFirstResponseByte(time.Since(start).Seconds())
-				}
-			},
-			Got100Continue: func() {
-				if it.Got100Continue != nil {
-					it.Got100Continue(time.Since(start).Seconds())
-				}
-			},
-			TLSHandshakeStart: func() {
-				if it.TLSHandshakeStart != nil {
-					it.TLSHandshakeStart(time.Since(start).Seconds())
-				}
-			},
-			TLSHandshakeDone: func(_ tls.ConnectionState, err error) {
-				if err != nil {
-					return
-				}
-				if it.TLSHandshakeDone != nil {
-					it.TLSHandshakeDone(time.Since(start).Seconds())
-				}
-			},
-			WroteHeaders: func() {
-				if it.WroteHeaders != nil {
-					it.WroteHeaders(time.Since(start).Seconds())
-				}
-			},
-			Wait100Continue: func() {
-				if it.Wait100Continue != nil {
-					it.Wait100Continue(time.Since(start).Seconds())
-				}
-			},
-			WroteRequest: func(_ httptrace.WroteRequestInfo) {
-				if it.WroteRequest != nil {
-					it.WroteRequest(time.Since(start).Seconds())
-				}
-			},
-		}
-		r = r.WithContext(httptrace.WithClientTrace(context.Background(), trace))
-
-		return next.RoundTrip(r)
-	})
-}

vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go

@@ -1,505 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package promhttp
-
-import (
-	"bufio"
-	"io"
-	"net"
-	"net/http"
-	"strconv"
-	"strings"
-	"time"
-
-	dto "github.com/prometheus/client_model/go"
-
-	"github.com/prometheus/client_golang/prometheus"
-)
-
-// magicString is used for the hacky label test in checkLabels. Remove once fixed.
-const magicString = "zZgWfBxLqvG8kc8IMv3POi2Bb0tZI3vAnBx+gBaFi9FyPzB/CzKUer1yufDa"
-
-// InstrumentHandlerInFlight is a middleware that wraps the provided
-// http.Handler. It sets the provided prometheus.Gauge to the number of
-// requests currently handled by the wrapped http.Handler.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerInFlight(g prometheus.Gauge, next http.Handler) http.Handler {
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		g.Inc()
-		defer g.Dec()
-		next.ServeHTTP(w, r)
-	})
-}
-
-// InstrumentHandlerDuration is a middleware that wraps the provided
-// http.Handler to observe the request duration with the provided ObserverVec.
-// The ObserverVec must have zero, one, or two labels. The only allowed label
-// names are "code" and "method". The function panics if any other instance
-// labels are provided. The Observe method of the Observer in the ObserverVec
-// is called with the request duration in seconds. Partitioning happens by HTTP
-// status code and/or HTTP method if the respective instance label names are
-// present in the ObserverVec. For unpartitioned observations, use an
-// ObserverVec with zero labels. Note that partitioning of Histograms is
-// expensive and should be used judiciously.
-//
-// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
-//
-// If the wrapped Handler panics, no values are reported.
-func InstrumentHandlerDuration(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc {
-	code, method := checkLabels(obs)
-
-	if code {
-		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			now := time.Now()
-			d := newDelegator(w, nil)
-			next.ServeHTTP(d, r)
-
-			obs.With(labels(code, method, r.Method, d.Status())).Observe(time.Since(now).Seconds())
-		})
-	}
-
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		now := time.Now()
-		next.ServeHTTP(w, r)
-		obs.With(labels(code, method, r.Method, 0)).Observe(time.Since(now).Seconds())
-	})
-}
-
-// InstrumentHandlerCounter is a middleware that wraps the provided
-// http.Handler to observe the request result with the provided CounterVec.
-// The CounterVec must have zero, one, or two labels. The only allowed label
-// names are "code" and "method". The function panics if any other instance
-// labels are provided. Partitioning of the CounterVec happens by HTTP status
-// code and/or HTTP method if the respective instance label names are present
-// in the CounterVec. For unpartitioned counting, use a CounterVec with
-// zero labels.
-//
-// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
-//
-// If the wrapped Handler panics, the Counter is not incremented.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerCounter(counter *prometheus.CounterVec, next http.Handler) http.HandlerFunc {
-	code, method := checkLabels(counter)
-
-	if code {
-		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			d := newDelegator(w, nil)
-			next.ServeHTTP(d, r)
-			counter.With(labels(code, method, r.Method, d.Status())).Inc()
-		})
-	}
-
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		next.ServeHTTP(w, r)
-		counter.With(labels(code, method, r.Method, 0)).Inc()
-	})
-}
-
-// InstrumentHandlerTimeToWriteHeader is a middleware that wraps the provided
-// http.Handler to observe with the provided ObserverVec the request duration
-// until the response headers are written. The ObserverVec must have zero, one,
-// or two labels. The only allowed label names are "code" and "method". The
-// function panics if any other instance labels are provided. The Observe
-// method of the Observer in the ObserverVec is called with the request
-// duration in seconds. Partitioning happens by HTTP status code and/or HTTP
-// method if the respective instance label names are present in the
-// ObserverVec. For unpartitioned observations, use an ObserverVec with zero
-// labels. Note that partitioning of Histograms is expensive and should be used
-// judiciously.
-//
-// If the wrapped Handler panics before calling WriteHeader, no value is
-// reported.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerTimeToWriteHeader(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc {
-	code, method := checkLabels(obs)
-
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		now := time.Now()
-		d := newDelegator(w, func(status int) {
-			obs.With(labels(code, method, r.Method, status)).Observe(time.Since(now).Seconds())
-		})
-		next.ServeHTTP(d, r)
-	})
-}
-
-// InstrumentHandlerRequestSize is a middleware that wraps the provided
-// http.Handler to observe the request size with the provided ObserverVec.
-// The ObserverVec must have zero, one, or two labels. The only allowed label
-// names are "code" and "method". The function panics if any other instance
-// labels are provided. The Observe method of the Observer in the ObserverVec
-// is called with the request size in bytes. Partitioning happens by HTTP
-// status code and/or HTTP method if the respective instance label names are
-// present in the ObserverVec. For unpartitioned observations, use an
-// ObserverVec with zero labels. Note that partitioning of Histograms is
-// expensive and should be used judiciously.
-//
-// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
-//
-// If the wrapped Handler panics, no values are reported.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerRequestSize(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc {
-	code, method := checkLabels(obs)
-
-	if code {
-		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			d := newDelegator(w, nil)
-			next.ServeHTTP(d, r)
-			size := computeApproximateRequestSize(r)
-			obs.With(labels(code, method, r.Method, d.Status())).Observe(float64(size))
-		})
-	}
-
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		next.ServeHTTP(w, r)
-		size := computeApproximateRequestSize(r)
-		obs.With(labels(code, method, r.Method, 0)).Observe(float64(size))
-	})
-}
-
-// InstrumentHandlerResponseSize is a middleware that wraps the provided
-// http.Handler to observe the response size with the provided ObserverVec.
-// The ObserverVec must have zero, one, or two labels. The only allowed label
-// names are "code" and "method". The function panics if any other instance
-// labels are provided. The Observe method of the Observer in the ObserverVec
-// is called with the response size in bytes. Partitioning happens by HTTP
-// status code and/or HTTP method if the respective instance label names are
-// present in the ObserverVec. For unpartitioned observations, use an
-// ObserverVec with zero labels. Note that partitioning of Histograms is
-// expensive and should be used judiciously.
-//
-// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
-//
-// If the wrapped Handler panics, no values are reported.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerResponseSize(obs prometheus.ObserverVec, next http.Handler) http.Handler {
-	code, method := checkLabels(obs)
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		d := newDelegator(w, nil)
-		next.ServeHTTP(d, r)
-		obs.With(labels(code, method, r.Method, d.Status())).Observe(float64(d.Written()))
-	})
-}
-
-func checkLabels(c prometheus.Collector) (code bool, method bool) {
-	// TODO(beorn7): Remove this hacky way to check for instance labels
-	// once Descriptors can have their dimensionality queried.
-	var (
-		desc *prometheus.Desc
-		pm   dto.Metric
-	)
-
-	descc := make(chan *prometheus.Desc, 1)
-	c.Describe(descc)
-
-	select {
-	case desc = <-descc:
-	default:
-		panic("no description provided by collector")
-	}
-	select {
-	case <-descc:
-		panic("more than one description provided by collector")
-	default:
-	}
-
-	close(descc)
-
-	if _, err := prometheus.NewConstMetric(desc, prometheus.UntypedValue, 0); err == nil {
-		return
-	}
-	if m, err := prometheus.NewConstMetric(desc, prometheus.UntypedValue, 0, magicString); err == nil {
-		if err := m.Write(&pm); err != nil {
-			panic("error checking metric for labels")
-		}
-		for _, label := range pm.Label {
-			name, value := label.GetName(), label.GetValue()
-			if value != magicString {
-				continue
-			}
-			switch name {
-			case "code":
-				code = true
-			case "method":
-				method = true
-			default:
-				panic("metric partitioned with non-supported labels")
-			}
-			return
-		}
-		panic("previously set label not found – this must never happen")
-	}
-	if m, err := prometheus.NewConstMetric(desc, prometheus.UntypedValue, 0, magicString, magicString); err == nil {
-		if err := m.Write(&pm); err != nil {
-			panic("error checking metric for labels")
-		}
-		for _, label := range pm.Label {
-			name, value := label.GetName(), label.GetValue()
-			if value != magicString {
-				continue
-			}
-			if name == "code" || name == "method" {
-				continue
-			}
-			panic("metric partitioned with non-supported labels")
-		}
-		code = true
-		method = true
-		return
-	}
-	panic("metric partitioned with non-supported labels")
-}
-
-// emptyLabels is a one-time allocation for non-partitioned metrics to avoid
-// unnecessary allocations on each request.
-var emptyLabels = prometheus.Labels{}
-
-func labels(code, method bool, reqMethod string, status int) prometheus.Labels {
-	if !(code || method) {
-		return emptyLabels
-	}
-	labels := prometheus.Labels{}
-
-	if code {
-		labels["code"] = sanitizeCode(status)
-	}
-	if method {
-		labels["method"] = sanitizeMethod(reqMethod)
-	}
-
-	return labels
-}
-
-func computeApproximateRequestSize(r *http.Request) int {
-	s := 0
-	if r.URL != nil {
-		s += len(r.URL.String())
-	}
-
-	s += len(r.Method)
-	s += len(r.Proto)
-	for name, values := range r.Header {
-		s += len(name)
-		for _, value := range values {
-			s += len(value)
-		}
-	}
-	s += len(r.Host)
-
-	// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
-
-	if r.ContentLength != -1 {
-		s += int(r.ContentLength)
-	}
-	return s
-}
-
-func sanitizeMethod(m string) string {
-	switch m {
-	case "GET", "get":
-		return "get"
-	case "PUT", "put":
-		return "put"
-	case "HEAD", "head":
-		return "head"
-	case "POST", "post":
-		return "post"
-	case "DELETE", "delete":
-		return "delete"
-	case "CONNECT", "connect":
-		return "connect"
-	case "OPTIONS", "options":
-		return "options"
-	case "NOTIFY", "notify":
-		return "notify"
-	default:
-		return strings.ToLower(m)
-	}
-}
-
-// If the wrapped http.Handler has not set a status code, i.e. the value is
-// currently 0, santizeCode will return 200, for consistency with behavior in
-// the stdlib.
-func sanitizeCode(s int) string {
-	switch s {
-	case 100:
-		return "100"
-	case 101:
-		return "101"
-
-	case 200, 0:
-		return "200"
-	case 201:
-		return "201"
-	case 202:
-		return "202"
-	case 203:
-		return "203"
-	case 204:
-		return "204"
-	case 205:
-		return "205"
-	case 206:
-		return "206"
-
-	case 300:
-		return "300"
-	case 301:
-		return "301"
-	case 302:
-		return "302"
-	case 304:
-		return "304"
-	case 305:
-		return "305"
-	case 307:
-		return "307"
-
-	case 400:
-		return "400"
-	case 401:
-		return "401"
-	case 402:
-		return "402"
-	case 403:
-		return "403"
-	case 404:
-		return "404"
-	case 405:
-		return "405"
-	case 406:
-		return "406"
-	case 407:
-		return "407"
-	case 408:
-		return "408"
-	case 409:
-		return "409"
-	case 410:
-		return "410"
-	case 411:
-		return "411"
-	case 412:
-		return "412"
-	case 413:
-		return "413"
-	case 414:
-		return "414"
-	case 415:
-		return "415"
-	case 416:
-		return "416"
-	case 417:
-		return "417"
-	case 418:
-		return "418"
-
-	case 500:
-		return "500"
-	case 501:
-		return "501"
-	case 502:
-		return "502"
-	case 503:
-		return "503"
-	case 504:
-		return "504"
-	case 505:
-		return "505"
-
-	case 428:
-		return "428"
-	case 429:
-		return "429"
-	case 431:
-		return "431"
-	case 511:
-		return "511"
-
-	default:
-		return strconv.Itoa(s)
-	}
-}
-
-type delegator interface {
-	Status() int
-	Written() int64
-
-	http.ResponseWriter
-}
-
-type responseWriterDelegator struct {
-	http.ResponseWriter
-
-	handler, method    string
-	status             int
-	written            int64
-	wroteHeader        bool
-	observeWriteHeader func(int)
-}
-
-func (r *responseWriterDelegator) Status() int {
-	return r.status
-}
-
-func (r *responseWriterDelegator) Written() int64 {
-	return r.written
-}
-
-func (r *responseWriterDelegator) WriteHeader(code int) {
-	r.status = code
-	r.wroteHeader = true
-	r.ResponseWriter.WriteHeader(code)
-	if r.observeWriteHeader != nil {
-		r.observeWriteHeader(code)
-	}
-}
-
-func (r *responseWriterDelegator) Write(b []byte) (int, error) {
-	if !r.wroteHeader {
-		r.WriteHeader(http.StatusOK)
-	}
-	n, err := r.ResponseWriter.Write(b)
-	r.written += int64(n)
-	return n, err
-}
-
-type fancyDelegator struct {
-	*responseWriterDelegator
-}
-
-func (r *fancyDelegator) CloseNotify() <-chan bool {
-	return r.ResponseWriter.(http.CloseNotifier).CloseNotify()
-}
-
-func (r *fancyDelegator) Hijack() (net.Conn, *bufio.ReadWriter, error) {
-	return r.ResponseWriter.(http.Hijacker).Hijack()
-}
-
-func (r *fancyDelegator) Flush() {
-	r.ResponseWriter.(http.Flusher).Flush()
-}
-
-func (r *fancyDelegator) ReadFrom(re io.Reader) (int64, error) {
-	if !r.wroteHeader {
-		r.WriteHeader(http.StatusOK)
-	}
-	n, err := r.ResponseWriter.(io.ReaderFrom).ReadFrom(re)
-	r.written += n
-	return n, err
-}

vendor/github.com/prometheus/client_golang/prometheus/push/examples_test.go

@@ -0,0 +1,56 @@
+// Copyright 2016 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package push_test
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/push"
+)
+
+func ExampleCollectors() {
+	completionTime := prometheus.NewGauge(prometheus.GaugeOpts{
+		Name: "db_backup_last_completion_timestamp_seconds",
+		Help: "The timestamp of the last succesful completion of a DB backup.",
+	})
+	completionTime.Set(float64(time.Now().Unix()))
+	if err := push.Collectors(
+		"db_backup", push.HostnameGroupingKey(),
+		"http://pushgateway:9091",
+		completionTime,
+	); err != nil {
+		fmt.Println("Could not push completion time to Pushgateway:", err)
+	}
+}
+
+func ExampleRegistry() {
+	registry := prometheus.NewRegistry()
+
+	completionTime := prometheus.NewGauge(prometheus.GaugeOpts{
+		Name: "db_backup_last_completion_timestamp_seconds",
+		Help: "The timestamp of the last succesful completion of a DB backup.",
+	})
+	registry.MustRegister(completionTime)
+
+	completionTime.Set(float64(time.Now().Unix()))
+	if err := push.FromGatherer(
+		"db_backup", push.HostnameGroupingKey(),
+		"http://pushgateway:9091",
+		registry,
+	); err != nil {
+		fmt.Println("Could not push completion time to Pushgateway:", err)
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/push/push.go

@@ -0,0 +1,172 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Copyright (c) 2013, The Prometheus Authors
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+// Package push provides functions to push metrics to a Pushgateway. The metrics
+// to push are either collected from a provided registry, or from explicitly
+// listed collectors.
+//
+// See the documentation of the Pushgateway to understand the meaning of the
+// grouping parameters and the differences between push.Registry and
+// push.Collectors on the one hand and push.AddRegistry and push.AddCollectors
+// on the other hand: https://github.com/prometheus/pushgateway
+package push
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"os"
+	"strings"
+
+	"github.com/prometheus/common/expfmt"
+	"github.com/prometheus/common/model"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+const contentTypeHeader = "Content-Type"
+
+// FromGatherer triggers a metric collection by the provided Gatherer (which is
+// usually implemented by a prometheus.Registry) and pushes all gathered metrics
+// to the Pushgateway specified by url, using the provided job name and the
+// (optional) further grouping labels (the grouping map may be nil). See the
+// Pushgateway documentation for detailed implications of the job and other
+// grouping labels. Neither the job name nor any grouping label value may
+// contain a "/". The metrics pushed must not contain a job label of their own
+// nor any of the grouping labels.
+//
+// You can use just host:port or ip:port as url, in which case 'http://' is
+// added automatically. You can also include the schema in the URL. However, do
+// not include the '/metrics/jobs/...' part.
+//
+// Note that all previously pushed metrics with the same job and other grouping
+// labels will be replaced with the metrics pushed by this call. (It uses HTTP
+// method 'PUT' to push to the Pushgateway.)
+func FromGatherer(job string, grouping map[string]string, url string, g prometheus.Gatherer) error {
+	return push(job, grouping, url, g, "PUT")
+}
+
+// AddFromGatherer works like FromGatherer, but only previously pushed metrics
+// with the same name (and the same job and other grouping labels) will be
+// replaced. (It uses HTTP method 'POST' to push to the Pushgateway.)
+func AddFromGatherer(job string, grouping map[string]string, url string, g prometheus.Gatherer) error {
+	return push(job, grouping, url, g, "POST")
+}
+
+func push(job string, grouping map[string]string, pushURL string, g prometheus.Gatherer, method string) error {
+	if !strings.Contains(pushURL, "://") {
+		pushURL = "http://" + pushURL
+	}
+	if strings.HasSuffix(pushURL, "/") {
+		pushURL = pushURL[:len(pushURL)-1]
+	}
+
+	if strings.Contains(job, "/") {
+		return fmt.Errorf("job contains '/': %s", job)
+	}
+	urlComponents := []string{url.QueryEscape(job)}
+	for ln, lv := range grouping {
+		if !model.LabelNameRE.MatchString(ln) {
+			return fmt.Errorf("grouping label has invalid name: %s", ln)
+		}
+		if strings.Contains(lv, "/") {
+			return fmt.Errorf("value of grouping label %s contains '/': %s", ln, lv)
+		}
+		urlComponents = append(urlComponents, ln, lv)
+	}
+	pushURL = fmt.Sprintf("%s/metrics/job/%s", pushURL, strings.Join(urlComponents, "/"))
+
+	mfs, err := g.Gather()
+	if err != nil {
+		return err
+	}
+	buf := &bytes.Buffer{}
+	enc := expfmt.NewEncoder(buf, expfmt.FmtProtoDelim)
+	// Check for pre-existing grouping labels:
+	for _, mf := range mfs {
+		for _, m := range mf.GetMetric() {
+			for _, l := range m.GetLabel() {
+				if l.GetName() == "job" {
+					return fmt.Errorf("pushed metric %s (%s) already contains a job label", mf.GetName(), m)
+				}
+				if _, ok := grouping[l.GetName()]; ok {
+					return fmt.Errorf(
+						"pushed metric %s (%s) already contains grouping label %s",
+						mf.GetName(), m, l.GetName(),
+					)
+				}
+			}
+		}
+		enc.Encode(mf)
+	}
+	req, err := http.NewRequest(method, pushURL, buf)
+	if err != nil {
+		return err
+	}
+	req.Header.Set(contentTypeHeader, string(expfmt.FmtProtoDelim))
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != 202 {
+		body, _ := ioutil.ReadAll(resp.Body) // Ignore any further error as this is for an error message only.
+		return fmt.Errorf("unexpected status code %d while pushing to %s: %s", resp.StatusCode, pushURL, body)
+	}
+	return nil
+}
+
+// Collectors works like FromGatherer, but it does not use a Gatherer. Instead,
+// it collects from the provided collectors directly. It is a convenient way to
+// push only a few metrics.
+func Collectors(job string, grouping map[string]string, url string, collectors ...prometheus.Collector) error {
+	return pushCollectors(job, grouping, url, "PUT", collectors...)
+}
+
+// AddCollectors works like AddFromGatherer, but it does not use a Gatherer.
+// Instead, it collects from the provided collectors directly. It is a
+// convenient way to push only a few metrics.
+func AddCollectors(job string, grouping map[string]string, url string, collectors ...prometheus.Collector) error {
+	return pushCollectors(job, grouping, url, "POST", collectors...)
+}
+
+func pushCollectors(job string, grouping map[string]string, url, method string, collectors ...prometheus.Collector) error {
+	r := prometheus.NewRegistry()
+	for _, collector := range collectors {
+		if err := r.Register(collector); err != nil {
+			return err
+		}
+	}
+	return push(job, grouping, url, r, method)
+}
+
+// HostnameGroupingKey returns a label map with the only entry
+// {instance="<hostname>"}. This can be conveniently used as the grouping
+// parameter if metrics should be pushed with the hostname as label. The
+// returned map is created upon each call so that the caller is free to add more
+// labels to the map.
+func HostnameGroupingKey() map[string]string {
+	hostname, err := os.Hostname()
+	if err != nil {
+		return map[string]string{"instance": "unknown"}
+	}
+	return map[string]string{"instance": hostname}
+}

vendor/github.com/prometheus/client_golang/prometheus/push/push_test.go

@@ -0,0 +1,176 @@
+// Copyright 2016 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Copyright (c) 2013, The Prometheus Authors
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+package push
+
+import (
+	"bytes"
+	"io/ioutil"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"testing"
+
+	"github.com/prometheus/common/expfmt"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+func TestPush(t *testing.T) {
+
+	var (
+		lastMethod string
+		lastBody   []byte
+		lastPath   string
+	)
+
+	host, err := os.Hostname()
+	if err != nil {
+		t.Error(err)
+	}
+
+	// Fake a Pushgateway that always responds with 202.
+	pgwOK := httptest.NewServer(
+		http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			lastMethod = r.Method
+			var err error
+			lastBody, err = ioutil.ReadAll(r.Body)
+			if err != nil {
+				t.Fatal(err)
+			}
+			lastPath = r.URL.EscapedPath()
+			w.Header().Set("Content-Type", `text/plain; charset=utf-8`)
+			w.WriteHeader(http.StatusAccepted)
+		}),
+	)
+	defer pgwOK.Close()
+
+	// Fake a Pushgateway that always responds with 500.
+	pgwErr := httptest.NewServer(
+		http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			http.Error(w, "fake error", http.StatusInternalServerError)
+		}),
+	)
+	defer pgwErr.Close()
+
+	metric1 := prometheus.NewCounter(prometheus.CounterOpts{
+		Name: "testname1",
+		Help: "testhelp1",
+	})
+	metric2 := prometheus.NewGauge(prometheus.GaugeOpts{
+		Name:        "testname2",
+		Help:        "testhelp2",
+		ConstLabels: prometheus.Labels{"foo": "bar", "dings": "bums"},
+	})
+
+	reg := prometheus.NewRegistry()
+	reg.MustRegister(metric1)
+	reg.MustRegister(metric2)
+
+	mfs, err := reg.Gather()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	buf := &bytes.Buffer{}
+	enc := expfmt.NewEncoder(buf, expfmt.FmtProtoDelim)
+
+	for _, mf := range mfs {
+		if err := enc.Encode(mf); err != nil {
+			t.Fatal(err)
+		}
+	}
+	wantBody := buf.Bytes()
+
+	// PushCollectors, all good.
+	if err := Collectors("testjob", HostnameGroupingKey(), pgwOK.URL, metric1, metric2); err != nil {
+		t.Fatal(err)
+	}
+	if lastMethod != "PUT" {
+		t.Error("want method PUT for PushCollectors, got", lastMethod)
+	}
+	if bytes.Compare(lastBody, wantBody) != 0 {
+		t.Errorf("got body %v, want %v", lastBody, wantBody)
+	}
+	if lastPath != "/metrics/job/testjob/instance/"+host {
+		t.Error("unexpected path:", lastPath)
+	}
+
+	// PushAddCollectors, with nil grouping, all good.
+	if err := AddCollectors("testjob", nil, pgwOK.URL, metric1, metric2); err != nil {
+		t.Fatal(err)
+	}
+	if lastMethod != "POST" {
+		t.Error("want method POST for PushAddCollectors, got", lastMethod)
+	}
+	if bytes.Compare(lastBody, wantBody) != 0 {
+		t.Errorf("got body %v, want %v", lastBody, wantBody)
+	}
+	if lastPath != "/metrics/job/testjob" {
+		t.Error("unexpected path:", lastPath)
+	}
+
+	// PushCollectors with a broken PGW.
+	if err := Collectors("testjob", nil, pgwErr.URL, metric1, metric2); err == nil {
+		t.Error("push to broken Pushgateway succeeded")
+	} else {
+		if got, want := err.Error(), "unexpected status code 500 while pushing to "+pgwErr.URL+"/metrics/job/testjob: fake error\n"; got != want {
+			t.Errorf("got error %q, want %q", got, want)
+		}
+	}
+
+	// PushCollectors with invalid grouping or job.
+	if err := Collectors("testjob", map[string]string{"foo": "bums"}, pgwErr.URL, metric1, metric2); err == nil {
+		t.Error("push with grouping contained in metrics succeeded")
+	}
+	if err := Collectors("test/job", nil, pgwErr.URL, metric1, metric2); err == nil {
+		t.Error("push with invalid job value succeeded")
+	}
+	if err := Collectors("testjob", map[string]string{"foo/bar": "bums"}, pgwErr.URL, metric1, metric2); err == nil {
+		t.Error("push with invalid grouping succeeded")
+	}
+	if err := Collectors("testjob", map[string]string{"foo-bar": "bums"}, pgwErr.URL, metric1, metric2); err == nil {
+		t.Error("push with invalid grouping succeeded")
+	}
+
+	// Push registry, all good.
+	if err := FromGatherer("testjob", HostnameGroupingKey(), pgwOK.URL, reg); err != nil {
+		t.Fatal(err)
+	}
+	if lastMethod != "PUT" {
+		t.Error("want method PUT for Push, got", lastMethod)
+	}
+	if bytes.Compare(lastBody, wantBody) != 0 {
+		t.Errorf("got body %v, want %v", lastBody, wantBody)
+	}
+
+	// PushAdd registry, all good.
+	if err := AddFromGatherer("testjob", map[string]string{"a": "x", "b": "y"}, pgwOK.URL, reg); err != nil {
+		t.Fatal(err)
+	}
+	if lastMethod != "POST" {
+		t.Error("want method POSTT for PushAdd, got", lastMethod)
+	}
+	if bytes.Compare(lastBody, wantBody) != 0 {
+		t.Errorf("got body %v, want %v", lastBody, wantBody)
+	}
+	if lastPath != "/metrics/job/testjob/a/x/b/y" && lastPath != "/metrics/job/testjob/b/y/a/x" {
+		t.Error("unexpected path:", lastPath)
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/registry.go

@@ -152,6 +152,38 @@ func MustRegister(cs ...Collector) {
 	DefaultRegisterer.MustRegister(cs...)
 }
 
+// RegisterOrGet registers the provided Collector with the DefaultRegisterer and
+// returns the Collector, unless an equal Collector was registered before, in
+// which case that Collector is returned.
+//
+// Deprecated: RegisterOrGet is merely a convenience function for the
+// implementation as described in the documentation for
+// AlreadyRegisteredError. As the use case is relatively rare, this function
+// will be removed in a future version of this package to clean up the
+// namespace.
+func RegisterOrGet(c Collector) (Collector, error) {
+	if err := Register(c); err != nil {
+		if are, ok := err.(AlreadyRegisteredError); ok {
+			return are.ExistingCollector, nil
+		}
+		return nil, err
+	}
+	return c, nil
+}
+
+// MustRegisterOrGet behaves like RegisterOrGet but panics instead of returning
+// an error.
+//
+// Deprecated: This is deprecated for the same reason RegisterOrGet is. See
+// there for details.
+func MustRegisterOrGet(c Collector) Collector {
+	c, err := RegisterOrGet(c)
+	if err != nil {
+		panic(err)
+	}
+	return c
+}
+
 // Unregister removes the registration of the provided Collector from the
 // DefaultRegisterer.
 //
@@ -169,6 +201,25 @@ func (gf GathererFunc) Gather() ([]*dto.MetricFamily, error) {
 	return gf()
 }
 
+// SetMetricFamilyInjectionHook replaces the DefaultGatherer with one that
+// gathers from the previous DefaultGatherers but then merges the MetricFamily
+// protobufs returned from the provided hook function with the MetricFamily
+// protobufs returned from the original DefaultGatherer.
+//
+// Deprecated: This function manipulates the DefaultGatherer variable. Consider
+// the implications, i.e. don't do this concurrently with any uses of the
+// DefaultGatherer. In the rare cases where you need to inject MetricFamily
+// protobufs directly, it is recommended to use a custom Registry and combine it
+// with a custom Gatherer using the Gatherers type (see
+// there). SetMetricFamilyInjectionHook only exists for compatibility reasons
+// with previous versions of this package.
+func SetMetricFamilyInjectionHook(hook func() []*dto.MetricFamily) {
+	DefaultGatherer = Gatherers{
+		DefaultGatherer,
+		GathererFunc(func() ([]*dto.MetricFamily, error) { return hook(), nil }),
+	}
+}
+
 // AlreadyRegisteredError is returned by the Register method if the Collector to
 // be registered has already been registered before, or a different Collector
 // that collects the same metrics has been registered before. Registration fails
@@ -243,7 +294,7 @@ func (r *Registry) Register(c Collector) error {
 	}()
 	r.mtx.Lock()
 	defer r.mtx.Unlock()
-	// Conduct various tests...
+	// Coduct various tests...
 	for desc := range descChan {
 
 		// Is the descriptor valid at all?
@@ -396,7 +447,7 @@ func (r *Registry) Gather() ([]*dto.MetricFamily, error) {
 
 	// Drain metricChan in case of premature return.
 	defer func() {
-		for range metricChan {
+		for _ = range metricChan {
 		}
 	}()
 
@@ -632,7 +683,7 @@ func (s metricSorter) Less(i, j int) bool {
 	return s[i].GetTimestampMs() < s[j].GetTimestampMs()
 }
 
-// normalizeMetricFamilies returns a MetricFamily slice with empty
+// normalizeMetricFamilies returns a MetricFamily slice whith empty
 // MetricFamilies pruned and the remaining MetricFamilies sorted by name within
 // the slice, with the contained Metrics sorted within each MetricFamily.
 func normalizeMetricFamilies(metricFamiliesByName map[string]*dto.MetricFamily) []*dto.MetricFamily {

vendor/github.com/prometheus/client_golang/prometheus/registry_test.go

@@ -0,0 +1,545 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Copyright (c) 2013, The Prometheus Authors
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+package prometheus_test
+
+import (
+	"bytes"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/prometheus/common/expfmt"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+)
+
+func testHandler(t testing.TB) {
+
+	metricVec := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Name:        "name",
+			Help:        "docstring",
+			ConstLabels: prometheus.Labels{"constname": "constvalue"},
+		},
+		[]string{"labelname"},
+	)
+
+	metricVec.WithLabelValues("val1").Inc()
+	metricVec.WithLabelValues("val2").Inc()
+
+	externalMetricFamily := &dto.MetricFamily{
+		Name: proto.String("externalname"),
+		Help: proto.String("externaldocstring"),
+		Type: dto.MetricType_COUNTER.Enum(),
+		Metric: []*dto.Metric{
+			{
+				Label: []*dto.LabelPair{
+					{
+						Name:  proto.String("externalconstname"),
+						Value: proto.String("externalconstvalue"),
+					},
+					{
+						Name:  proto.String("externallabelname"),
+						Value: proto.String("externalval1"),
+					},
+				},
+				Counter: &dto.Counter{
+					Value: proto.Float64(1),
+				},
+			},
+		},
+	}
+	externalBuf := &bytes.Buffer{}
+	enc := expfmt.NewEncoder(externalBuf, expfmt.FmtProtoDelim)
+	if err := enc.Encode(externalMetricFamily); err != nil {
+		t.Fatal(err)
+	}
+	externalMetricFamilyAsBytes := externalBuf.Bytes()
+	externalMetricFamilyAsText := []byte(`# HELP externalname externaldocstring
+# TYPE externalname counter
+externalname{externalconstname="externalconstvalue",externallabelname="externalval1"} 1
+`)
+	externalMetricFamilyAsProtoText := []byte(`name: "externalname"
+help: "externaldocstring"
+type: COUNTER
+metric: <
+  label: <
+    name: "externalconstname"
+    value: "externalconstvalue"
+  >
+  label: <
+    name: "externallabelname"
+    value: "externalval1"
+  >
+  counter: <
+    value: 1
+  >
+>
+
+`)
+	externalMetricFamilyAsProtoCompactText := []byte(`name:"externalname" help:"externaldocstring" type:COUNTER metric:<label:<name:"externalconstname" value:"externalconstvalue" > label:<name:"externallabelname" value:"externalval1" > counter:<value:1 > > 
+`)
+
+	expectedMetricFamily := &dto.MetricFamily{
+		Name: proto.String("name"),
+		Help: proto.String("docstring"),
+		Type: dto.MetricType_COUNTER.Enum(),
+		Metric: []*dto.Metric{
+			{
+				Label: []*dto.LabelPair{
+					{
+						Name:  proto.String("constname"),
+						Value: proto.String("constvalue"),
+					},
+					{
+						Name:  proto.String("labelname"),
+						Value: proto.String("val1"),
+					},
+				},
+				Counter: &dto.Counter{
+					Value: proto.Float64(1),
+				},
+			},
+			{
+				Label: []*dto.LabelPair{
+					{
+						Name:  proto.String("constname"),
+						Value: proto.String("constvalue"),
+					},
+					{
+						Name:  proto.String("labelname"),
+						Value: proto.String("val2"),
+					},
+				},
+				Counter: &dto.Counter{
+					Value: proto.Float64(1),
+				},
+			},
+		},
+	}
+	buf := &bytes.Buffer{}
+	enc = expfmt.NewEncoder(buf, expfmt.FmtProtoDelim)
+	if err := enc.Encode(expectedMetricFamily); err != nil {
+		t.Fatal(err)
+	}
+	expectedMetricFamilyAsBytes := buf.Bytes()
+	expectedMetricFamilyAsText := []byte(`# HELP name docstring
+# TYPE name counter
+name{constname="constvalue",labelname="val1"} 1
+name{constname="constvalue",labelname="val2"} 1
+`)
+	expectedMetricFamilyAsProtoText := []byte(`name: "name"
+help: "docstring"
+type: COUNTER
+metric: <
+  label: <
+    name: "constname"
+    value: "constvalue"
+  >
+  label: <
+    name: "labelname"
+    value: "val1"
+  >
+  counter: <
+    value: 1
+  >
+>
+metric: <
+  label: <
+    name: "constname"
+    value: "constvalue"
+  >
+  label: <
+    name: "labelname"
+    value: "val2"
+  >
+  counter: <
+    value: 1
+  >
+>
+
+`)
+	expectedMetricFamilyAsProtoCompactText := []byte(`name:"name" help:"docstring" type:COUNTER metric:<label:<name:"constname" value:"constvalue" > label:<name:"labelname" value:"val1" > counter:<value:1 > > metric:<label:<name:"constname" value:"constvalue" > label:<name:"labelname" value:"val2" > counter:<value:1 > > 
+`)
+
+	externalMetricFamilyWithSameName := &dto.MetricFamily{
+		Name: proto.String("name"),
+		Help: proto.String("docstring"),
+		Type: dto.MetricType_COUNTER.Enum(),
+		Metric: []*dto.Metric{
+			{
+				Label: []*dto.LabelPair{
+					{
+						Name:  proto.String("constname"),
+						Value: proto.String("constvalue"),
+					},
+					{
+						Name:  proto.String("labelname"),
+						Value: proto.String("different_val"),
+					},
+				},
+				Counter: &dto.Counter{
+					Value: proto.Float64(42),
+				},
+			},
+		},
+	}
+
+	expectedMetricFamilyMergedWithExternalAsProtoCompactText := []byte(`name:"name" help:"docstring" type:COUNTER metric:<label:<name:"constname" value:"constvalue" > label:<name:"labelname" value:"different_val" > counter:<value:42 > > metric:<label:<name:"constname" value:"constvalue" > label:<name:"labelname" value:"val1" > counter:<value:1 > > metric:<label:<name:"constname" value:"constvalue" > label:<name:"labelname" value:"val2" > counter:<value:1 > > 
+`)
+
+	type output struct {
+		headers map[string]string
+		body    []byte
+	}
+
+	var scenarios = []struct {
+		headers    map[string]string
+		out        output
+		collector  prometheus.Collector
+		externalMF []*dto.MetricFamily
+	}{
+		{ // 0
+			headers: map[string]string{
+				"Accept": "foo/bar;q=0.2, dings/bums;q=0.8",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `text/plain; version=0.0.4`,
+				},
+				body: []byte{},
+			},
+		},
+		{ // 1
+			headers: map[string]string{
+				"Accept": "foo/bar;q=0.2, application/quark;q=0.8",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `text/plain; version=0.0.4`,
+				},
+				body: []byte{},
+			},
+		},
+		{ // 2
+			headers: map[string]string{
+				"Accept": "foo/bar;q=0.2, application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=bla;q=0.8",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `text/plain; version=0.0.4`,
+				},
+				body: []byte{},
+			},
+		},
+		{ // 3
+			headers: map[string]string{
+				"Accept": "text/plain;q=0.2, application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=delimited;q=0.8",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=delimited`,
+				},
+				body: []byte{},
+			},
+		},
+		{ // 4
+			headers: map[string]string{
+				"Accept": "application/json",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `text/plain; version=0.0.4`,
+				},
+				body: expectedMetricFamilyAsText,
+			},
+			collector: metricVec,
+		},
+		{ // 5
+			headers: map[string]string{
+				"Accept": "application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=delimited",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=delimited`,
+				},
+				body: expectedMetricFamilyAsBytes,
+			},
+			collector: metricVec,
+		},
+		{ // 6
+			headers: map[string]string{
+				"Accept": "application/json",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `text/plain; version=0.0.4`,
+				},
+				body: externalMetricFamilyAsText,
+			},
+			externalMF: []*dto.MetricFamily{externalMetricFamily},
+		},
+		{ // 7
+			headers: map[string]string{
+				"Accept": "application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=delimited",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=delimited`,
+				},
+				body: externalMetricFamilyAsBytes,
+			},
+			externalMF: []*dto.MetricFamily{externalMetricFamily},
+		},
+		{ // 8
+			headers: map[string]string{
+				"Accept": "application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=delimited",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=delimited`,
+				},
+				body: bytes.Join(
+					[][]byte{
+						externalMetricFamilyAsBytes,
+						expectedMetricFamilyAsBytes,
+					},
+					[]byte{},
+				),
+			},
+			collector:  metricVec,
+			externalMF: []*dto.MetricFamily{externalMetricFamily},
+		},
+		{ // 9
+			headers: map[string]string{
+				"Accept": "text/plain",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `text/plain; version=0.0.4`,
+				},
+				body: []byte{},
+			},
+		},
+		{ // 10
+			headers: map[string]string{
+				"Accept": "application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=bla;q=0.2, text/plain;q=0.5",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `text/plain; version=0.0.4`,
+				},
+				body: expectedMetricFamilyAsText,
+			},
+			collector: metricVec,
+		},
+		{ // 11
+			headers: map[string]string{
+				"Accept": "application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=bla;q=0.2, text/plain;q=0.5;version=0.0.4",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `text/plain; version=0.0.4`,
+				},
+				body: bytes.Join(
+					[][]byte{
+						externalMetricFamilyAsText,
+						expectedMetricFamilyAsText,
+					},
+					[]byte{},
+				),
+			},
+			collector:  metricVec,
+			externalMF: []*dto.MetricFamily{externalMetricFamily},
+		},
+		{ // 12
+			headers: map[string]string{
+				"Accept": "application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=delimited;q=0.2, text/plain;q=0.5;version=0.0.2",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=delimited`,
+				},
+				body: bytes.Join(
+					[][]byte{
+						externalMetricFamilyAsBytes,
+						expectedMetricFamilyAsBytes,
+					},
+					[]byte{},
+				),
+			},
+			collector:  metricVec,
+			externalMF: []*dto.MetricFamily{externalMetricFamily},
+		},
+		{ // 13
+			headers: map[string]string{
+				"Accept": "application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=text;q=0.5, application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=delimited;q=0.4",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=text`,
+				},
+				body: bytes.Join(
+					[][]byte{
+						externalMetricFamilyAsProtoText,
+						expectedMetricFamilyAsProtoText,
+					},
+					[]byte{},
+				),
+			},
+			collector:  metricVec,
+			externalMF: []*dto.MetricFamily{externalMetricFamily},
+		},
+		{ // 14
+			headers: map[string]string{
+				"Accept": "application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=compact-text",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=compact-text`,
+				},
+				body: bytes.Join(
+					[][]byte{
+						externalMetricFamilyAsProtoCompactText,
+						expectedMetricFamilyAsProtoCompactText,
+					},
+					[]byte{},
+				),
+			},
+			collector:  metricVec,
+			externalMF: []*dto.MetricFamily{externalMetricFamily},
+		},
+		{ // 15
+			headers: map[string]string{
+				"Accept": "application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=compact-text",
+			},
+			out: output{
+				headers: map[string]string{
+					"Content-Type": `application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=compact-text`,
+				},
+				body: bytes.Join(
+					[][]byte{
+						externalMetricFamilyAsProtoCompactText,
+						expectedMetricFamilyMergedWithExternalAsProtoCompactText,
+					},
+					[]byte{},
+				),
+			},
+			collector: metricVec,
+			externalMF: []*dto.MetricFamily{
+				externalMetricFamily,
+				externalMetricFamilyWithSameName,
+			},
+		},
+	}
+	for i, scenario := range scenarios {
+		registry := prometheus.NewPedanticRegistry()
+		gatherer := prometheus.Gatherer(registry)
+		if scenario.externalMF != nil {
+			gatherer = prometheus.Gatherers{
+				registry,
+				prometheus.GathererFunc(func() ([]*dto.MetricFamily, error) {
+					return scenario.externalMF, nil
+				}),
+			}
+		}
+
+		if scenario.collector != nil {
+			registry.Register(scenario.collector)
+		}
+		writer := httptest.NewRecorder()
+		handler := prometheus.InstrumentHandler("prometheus", promhttp.HandlerFor(gatherer, promhttp.HandlerOpts{}))
+		request, _ := http.NewRequest("GET", "/", nil)
+		for key, value := range scenario.headers {
+			request.Header.Add(key, value)
+		}
+		handler(writer, request)
+
+		for key, value := range scenario.out.headers {
+			if writer.HeaderMap.Get(key) != value {
+				t.Errorf(
+					"%d. expected %q for header %q, got %q",
+					i, value, key, writer.Header().Get(key),
+				)
+			}
+		}
+
+		if !bytes.Equal(scenario.out.body, writer.Body.Bytes()) {
+			t.Errorf(
+				"%d. expected body:\n%s\ngot body:\n%s\n",
+				i, scenario.out.body, writer.Body.Bytes(),
+			)
+		}
+	}
+}
+
+func TestHandler(t *testing.T) {
+	testHandler(t)
+}
+
+func BenchmarkHandler(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		testHandler(b)
+	}
+}
+
+func TestRegisterWithOrGet(t *testing.T) {
+	// Replace the default registerer just to be sure. This is bad, but this
+	// whole test will go away once RegisterOrGet is removed.
+	oldRegisterer := prometheus.DefaultRegisterer
+	defer func() {
+		prometheus.DefaultRegisterer = oldRegisterer
+	}()
+	prometheus.DefaultRegisterer = prometheus.NewRegistry()
+	original := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Name: "test",
+			Help: "help",
+		},
+		[]string{"foo", "bar"},
+	)
+	equalButNotSame := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Name: "test",
+			Help: "help",
+		},
+		[]string{"foo", "bar"},
+	)
+	if err := prometheus.Register(original); err != nil {
+		t.Fatal(err)
+	}
+	if err := prometheus.Register(equalButNotSame); err == nil {
+		t.Fatal("expected error when registringe equal collector")
+	}
+	existing, err := prometheus.RegisterOrGet(equalButNotSame)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if existing != original {
+		t.Error("expected original collector but got something else")
+	}
+	if existing == equalButNotSame {
+		t.Error("expected original callector but got new one")
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/summary.go

@@ -54,9 +54,6 @@ type Summary interface {
 }
 
 // DefObjectives are the default Summary quantile values.
-//
-// Deprecated: DefObjectives will not be used as the default objectives in
-// v0.10 of the library. The default Summary will have no quantiles then.
 var (
 	DefObjectives = map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001}
 
@@ -116,15 +113,9 @@ type SummaryOpts struct {
 	ConstLabels Labels
 
 	// Objectives defines the quantile rank estimates with their respective
-	// absolute error. If Objectives[q] = e, then the value reported for q
-	// will be the φ-quantile value for some φ between q-e and q+e.  The
-	// default value is DefObjectives. It is used if Objectives is left at
-	// its zero value (i.e. nil). To create a Summary without Objectives,
-	// set it to an empty map (i.e. map[float64]float64{}).
-	//
-	// Deprecated: Note that the current value of DefObjectives is
-	// deprecated. It will be replaced by an empty map in v0.10 of the
-	// library. Please explicitly set Objectives to the desired value.
+	// absolute error. If Objectives[q] = e, then the value reported
+	// for q will be the φ-quantile value for some φ between q-e and q+e.
+	// The default value is DefObjectives.
 	Objectives map[float64]float64
 
 	// MaxAge defines the duration for which an observation stays relevant
@@ -192,7 +183,7 @@ func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary {
 		}
 	}
 
-	if opts.Objectives == nil {
+	if len(opts.Objectives) == 0 {
 		opts.Objectives = DefObjectives
 	}
 
@@ -419,24 +410,24 @@ func NewSummaryVec(opts SummaryOpts, labelNames []string) *SummaryVec {
 	}
 }
 
-// GetMetricWithLabelValues replaces the method of the same name in MetricVec.
-// The difference is that this method returns an Observer and not a Metric so
-// that no type conversion to an Observer is required.
-func (m *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) {
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns a Summary and not a
+// Metric so that no type conversion is required.
+func (m *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Summary, error) {
 	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
 	if metric != nil {
-		return metric.(Observer), err
+		return metric.(Summary), err
 	}
 	return nil, err
 }
 
 // GetMetricWith replaces the method of the same name in MetricVec. The
-// difference is that this method returns an Observer and not a Metric so that
-// no type conversion to an Observer is required.
-func (m *SummaryVec) GetMetricWith(labels Labels) (Observer, error) {
+// difference is that this method returns a Summary and not a Metric so that no
+// type conversion is required.
+func (m *SummaryVec) GetMetricWith(labels Labels) (Summary, error) {
 	metric, err := m.MetricVec.GetMetricWith(labels)
 	if metric != nil {
-		return metric.(Observer), err
+		return metric.(Summary), err
 	}
 	return nil, err
 }
@@ -445,15 +436,15 @@ func (m *SummaryVec) GetMetricWith(labels Labels) (Observer, error) {
 // GetMetricWithLabelValues would have returned an error. By not returning an
 // error, WithLabelValues allows shortcuts like
 //     myVec.WithLabelValues("404", "GET").Observe(42.21)
-func (m *SummaryVec) WithLabelValues(lvs ...string) Observer {
-	return m.MetricVec.WithLabelValues(lvs...).(Observer)
+func (m *SummaryVec) WithLabelValues(lvs ...string) Summary {
+	return m.MetricVec.WithLabelValues(lvs...).(Summary)
 }
 
 // With works as GetMetricWith, but panics where GetMetricWithLabels would have
 // returned an error. By not returning an error, With allows shortcuts like
 //     myVec.With(Labels{"code": "404", "method": "GET"}).Observe(42.21)
-func (m *SummaryVec) With(labels Labels) Observer {
-	return m.MetricVec.With(labels).(Observer)
+func (m *SummaryVec) With(labels Labels) Summary {
+	return m.MetricVec.With(labels).(Summary)
 }
 
 type constSummary struct {

vendor/github.com/prometheus/client_golang/prometheus/summary_test.go

@@ -0,0 +1,347 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"math"
+	"math/rand"
+	"sort"
+	"sync"
+	"testing"
+	"testing/quick"
+	"time"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+func benchmarkSummaryObserve(w int, b *testing.B) {
+	b.StopTimer()
+
+	wg := new(sync.WaitGroup)
+	wg.Add(w)
+
+	g := new(sync.WaitGroup)
+	g.Add(1)
+
+	s := NewSummary(SummaryOpts{})
+
+	for i := 0; i < w; i++ {
+		go func() {
+			g.Wait()
+
+			for i := 0; i < b.N; i++ {
+				s.Observe(float64(i))
+			}
+
+			wg.Done()
+		}()
+	}
+
+	b.StartTimer()
+	g.Done()
+	wg.Wait()
+}
+
+func BenchmarkSummaryObserve1(b *testing.B) {
+	benchmarkSummaryObserve(1, b)
+}
+
+func BenchmarkSummaryObserve2(b *testing.B) {
+	benchmarkSummaryObserve(2, b)
+}
+
+func BenchmarkSummaryObserve4(b *testing.B) {
+	benchmarkSummaryObserve(4, b)
+}
+
+func BenchmarkSummaryObserve8(b *testing.B) {
+	benchmarkSummaryObserve(8, b)
+}
+
+func benchmarkSummaryWrite(w int, b *testing.B) {
+	b.StopTimer()
+
+	wg := new(sync.WaitGroup)
+	wg.Add(w)
+
+	g := new(sync.WaitGroup)
+	g.Add(1)
+
+	s := NewSummary(SummaryOpts{})
+
+	for i := 0; i < 1000000; i++ {
+		s.Observe(float64(i))
+	}
+
+	for j := 0; j < w; j++ {
+		outs := make([]dto.Metric, b.N)
+
+		go func(o []dto.Metric) {
+			g.Wait()
+
+			for i := 0; i < b.N; i++ {
+				s.Write(&o[i])
+			}
+
+			wg.Done()
+		}(outs)
+	}
+
+	b.StartTimer()
+	g.Done()
+	wg.Wait()
+}
+
+func BenchmarkSummaryWrite1(b *testing.B) {
+	benchmarkSummaryWrite(1, b)
+}
+
+func BenchmarkSummaryWrite2(b *testing.B) {
+	benchmarkSummaryWrite(2, b)
+}
+
+func BenchmarkSummaryWrite4(b *testing.B) {
+	benchmarkSummaryWrite(4, b)
+}
+
+func BenchmarkSummaryWrite8(b *testing.B) {
+	benchmarkSummaryWrite(8, b)
+}
+
+func TestSummaryConcurrency(t *testing.T) {
+	if testing.Short() {
+		t.Skip("Skipping test in short mode.")
+	}
+
+	rand.Seed(42)
+
+	it := func(n uint32) bool {
+		mutations := int(n%1e4 + 1e4)
+		concLevel := int(n%5 + 1)
+		total := mutations * concLevel
+
+		var start, end sync.WaitGroup
+		start.Add(1)
+		end.Add(concLevel)
+
+		sum := NewSummary(SummaryOpts{
+			Name: "test_summary",
+			Help: "helpless",
+		})
+
+		allVars := make([]float64, total)
+		var sampleSum float64
+		for i := 0; i < concLevel; i++ {
+			vals := make([]float64, mutations)
+			for j := 0; j < mutations; j++ {
+				v := rand.NormFloat64()
+				vals[j] = v
+				allVars[i*mutations+j] = v
+				sampleSum += v
+			}
+
+			go func(vals []float64) {
+				start.Wait()
+				for _, v := range vals {
+					sum.Observe(v)
+				}
+				end.Done()
+			}(vals)
+		}
+		sort.Float64s(allVars)
+		start.Done()
+		end.Wait()
+
+		m := &dto.Metric{}
+		sum.Write(m)
+		if got, want := int(*m.Summary.SampleCount), total; got != want {
+			t.Errorf("got sample count %d, want %d", got, want)
+		}
+		if got, want := *m.Summary.SampleSum, sampleSum; math.Abs((got-want)/want) > 0.001 {
+			t.Errorf("got sample sum %f, want %f", got, want)
+		}
+
+		objectives := make([]float64, 0, len(DefObjectives))
+		for qu := range DefObjectives {
+			objectives = append(objectives, qu)
+		}
+		sort.Float64s(objectives)
+
+		for i, wantQ := range objectives {
+			ε := DefObjectives[wantQ]
+			gotQ := *m.Summary.Quantile[i].Quantile
+			gotV := *m.Summary.Quantile[i].Value
+			min, max := getBounds(allVars, wantQ, ε)
+			if gotQ != wantQ {
+				t.Errorf("got quantile %f, want %f", gotQ, wantQ)
+			}
+			if gotV < min || gotV > max {
+				t.Errorf("got %f for quantile %f, want [%f,%f]", gotV, gotQ, min, max)
+			}
+		}
+		return true
+	}
+
+	if err := quick.Check(it, nil); err != nil {
+		t.Error(err)
+	}
+}
+
+func TestSummaryVecConcurrency(t *testing.T) {
+	if testing.Short() {
+		t.Skip("Skipping test in short mode.")
+	}
+
+	rand.Seed(42)
+
+	objectives := make([]float64, 0, len(DefObjectives))
+	for qu := range DefObjectives {
+
+		objectives = append(objectives, qu)
+	}
+	sort.Float64s(objectives)
+
+	it := func(n uint32) bool {
+		mutations := int(n%1e4 + 1e4)
+		concLevel := int(n%7 + 1)
+		vecLength := int(n%3 + 1)
+
+		var start, end sync.WaitGroup
+		start.Add(1)
+		end.Add(concLevel)
+
+		sum := NewSummaryVec(
+			SummaryOpts{
+				Name: "test_summary",
+				Help: "helpless",
+			},
+			[]string{"label"},
+		)
+
+		allVars := make([][]float64, vecLength)
+		sampleSums := make([]float64, vecLength)
+		for i := 0; i < concLevel; i++ {
+			vals := make([]float64, mutations)
+			picks := make([]int, mutations)
+			for j := 0; j < mutations; j++ {
+				v := rand.NormFloat64()
+				vals[j] = v
+				pick := rand.Intn(vecLength)
+				picks[j] = pick
+				allVars[pick] = append(allVars[pick], v)
+				sampleSums[pick] += v
+			}
+
+			go func(vals []float64) {
+				start.Wait()
+				for i, v := range vals {
+					sum.WithLabelValues(string('A' + picks[i])).Observe(v)
+				}
+				end.Done()
+			}(vals)
+		}
+		for _, vars := range allVars {
+			sort.Float64s(vars)
+		}
+		start.Done()
+		end.Wait()
+
+		for i := 0; i < vecLength; i++ {
+			m := &dto.Metric{}
+			s := sum.WithLabelValues(string('A' + i))
+			s.Write(m)
+			if got, want := int(*m.Summary.SampleCount), len(allVars[i]); got != want {
+				t.Errorf("got sample count %d for label %c, want %d", got, 'A'+i, want)
+			}
+			if got, want := *m.Summary.SampleSum, sampleSums[i]; math.Abs((got-want)/want) > 0.001 {
+				t.Errorf("got sample sum %f for label %c, want %f", got, 'A'+i, want)
+			}
+			for j, wantQ := range objectives {
+				ε := DefObjectives[wantQ]
+				gotQ := *m.Summary.Quantile[j].Quantile
+				gotV := *m.Summary.Quantile[j].Value
+				min, max := getBounds(allVars[i], wantQ, ε)
+				if gotQ != wantQ {
+					t.Errorf("got quantile %f for label %c, want %f", gotQ, 'A'+i, wantQ)
+				}
+				if gotV < min || gotV > max {
+					t.Errorf("got %f for quantile %f for label %c, want [%f,%f]", gotV, gotQ, 'A'+i, min, max)
+				}
+			}
+		}
+		return true
+	}
+
+	if err := quick.Check(it, nil); err != nil {
+		t.Error(err)
+	}
+}
+
+func TestSummaryDecay(t *testing.T) {
+	if testing.Short() {
+		t.Skip("Skipping test in short mode.")
+		// More because it depends on timing than because it is particularly long...
+	}
+
+	sum := NewSummary(SummaryOpts{
+		Name:       "test_summary",
+		Help:       "helpless",
+		MaxAge:     100 * time.Millisecond,
+		Objectives: map[float64]float64{0.1: 0.001},
+		AgeBuckets: 10,
+	})
+
+	m := &dto.Metric{}
+	i := 0
+	tick := time.NewTicker(time.Millisecond)
+	for _ = range tick.C {
+		i++
+		sum.Observe(float64(i))
+		if i%10 == 0 {
+			sum.Write(m)
+			if got, want := *m.Summary.Quantile[0].Value, math.Max(float64(i)/10, float64(i-90)); math.Abs(got-want) > 20 {
+				t.Errorf("%d. got %f, want %f", i, got, want)
+			}
+			m.Reset()
+		}
+		if i >= 1000 {
+			break
+		}
+	}
+	tick.Stop()
+	// Wait for MaxAge without observations and make sure quantiles are NaN.
+	time.Sleep(100 * time.Millisecond)
+	sum.Write(m)
+	if got := *m.Summary.Quantile[0].Value; !math.IsNaN(got) {
+		t.Errorf("got %f, want NaN after expiration", got)
+	}
+}
+
+func getBounds(vars []float64, q, ε float64) (min, max float64) {
+	// TODO(beorn7): This currently tolerates an error of up to 2*ε. The
+	// error must be at most ε, but for some reason, it's sometimes slightly
+	// higher. That's a bug.
+	n := float64(len(vars))
+	lower := int((q - 2*ε) * n)
+	upper := int(math.Ceil((q + 2*ε) * n))
+	min = vars[0]
+	if lower > 1 {
+		min = vars[lower-1]
+	}
+	max = vars[len(vars)-1]
+	if upper < len(vars) {
+		max = vars[upper-1]
+	}
+	return
+}

vendor/github.com/prometheus/client_golang/prometheus/timer.go

@@ -1,48 +0,0 @@
-// Copyright 2016 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import "time"
-
-// Timer is a helper type to time functions. Use NewTimer to create new
-// instances.
-type Timer struct {
-	begin    time.Time
-	observer Observer
-}
-
-// NewTimer creates a new Timer. The provided Observer is used to observe a
-// duration in seconds. Timer is usually used to time a function call in the
-// following way:
-//    func TimeMe() {
-//        timer := NewTimer(myHistogram)
-//        defer timer.ObserveDuration()
-//        // Do actual work.
-//    }
-func NewTimer(o Observer) *Timer {
-	return &Timer{
-		begin:    time.Now(),
-		observer: o,
-	}
-}
-
-// ObserveDuration records the duration passed since the Timer was created with
-// NewTimer. It calls the Observe method of the Observer provided during
-// construction with the duration in seconds as an argument. ObserveDuration is
-// usually called with a defer statement.
-func (t *Timer) ObserveDuration() {
-	if t.observer != nil {
-		t.observer.Observe(time.Since(t.begin).Seconds())
-	}
-}

vendor/github.com/prometheus/client_golang/prometheus/untyped.go

@@ -20,11 +20,6 @@ package prometheus
 // no type information is implied.
 //
 // To create Untyped instances, use NewUntyped.
-//
-// Deprecated: The Untyped type is deprecated because it doesn't make sense in
-// direct instrumentation. If you need to mirror an external metric of unknown
-// type (usually while writing exporters), Use MustNewConstMetric to create an
-// untyped metric instance on the fly.
 type Untyped interface {
 	Metric
 	Collector

vendor/github.com/prometheus/client_golang/prometheus/value.go

@@ -19,7 +19,6 @@ import (
 	"math"
 	"sort"
 	"sync/atomic"
-	"time"
 
 	dto "github.com/prometheus/client_model/go"
 
@@ -44,7 +43,7 @@ var errInconsistentCardinality = errors.New("inconsistent label cardinality")
 // ValueType. This is a low-level building block used by the library to back the
 // implementations of Counter, Gauge, and Untyped.
 type value struct {
-	// valBits contains the bits of the represented float64 value. It has
+	// valBits containst the bits of the represented float64 value. It has
 	// to go first in the struct to guarantee alignment for atomic
 	// operations.  http://golang.org/pkg/sync/atomic/#pkg-note-BUG
 	valBits uint64
@@ -81,10 +80,6 @@ func (v *value) Set(val float64) {
 	atomic.StoreUint64(&v.valBits, math.Float64bits(val))
 }
 
-func (v *value) SetToCurrentTime() {
-	v.Set(float64(time.Now().UnixNano()) / 1e9)
-}
-
 func (v *value) Inc() {
 	v.Add(1)
 }

vendor/github.com/prometheus/client_golang/prometheus/vec_test.go

@@ -0,0 +1,312 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"fmt"
+	"testing"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+func TestDelete(t *testing.T) {
+	vec := NewUntypedVec(
+		UntypedOpts{
+			Name: "test",
+			Help: "helpless",
+		},
+		[]string{"l1", "l2"},
+	)
+	testDelete(t, vec)
+}
+
+func TestDeleteWithCollisions(t *testing.T) {
+	vec := NewUntypedVec(
+		UntypedOpts{
+			Name: "test",
+			Help: "helpless",
+		},
+		[]string{"l1", "l2"},
+	)
+	vec.hashAdd = func(h uint64, s string) uint64 { return 1 }
+	vec.hashAddByte = func(h uint64, b byte) uint64 { return 1 }
+	testDelete(t, vec)
+}
+
+func testDelete(t *testing.T, vec *UntypedVec) {
+	if got, want := vec.Delete(Labels{"l1": "v1", "l2": "v2"}), false; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+
+	vec.With(Labels{"l1": "v1", "l2": "v2"}).(Untyped).Set(42)
+	if got, want := vec.Delete(Labels{"l1": "v1", "l2": "v2"}), true; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+	if got, want := vec.Delete(Labels{"l1": "v1", "l2": "v2"}), false; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+
+	vec.With(Labels{"l1": "v1", "l2": "v2"}).(Untyped).Set(42)
+	if got, want := vec.Delete(Labels{"l2": "v2", "l1": "v1"}), true; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+	if got, want := vec.Delete(Labels{"l2": "v2", "l1": "v1"}), false; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+
+	vec.With(Labels{"l1": "v1", "l2": "v2"}).(Untyped).Set(42)
+	if got, want := vec.Delete(Labels{"l2": "v1", "l1": "v2"}), false; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+	if got, want := vec.Delete(Labels{"l1": "v1"}), false; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+}
+
+func TestDeleteLabelValues(t *testing.T) {
+	vec := NewUntypedVec(
+		UntypedOpts{
+			Name: "test",
+			Help: "helpless",
+		},
+		[]string{"l1", "l2"},
+	)
+	testDeleteLabelValues(t, vec)
+}
+
+func TestDeleteLabelValuesWithCollisions(t *testing.T) {
+	vec := NewUntypedVec(
+		UntypedOpts{
+			Name: "test",
+			Help: "helpless",
+		},
+		[]string{"l1", "l2"},
+	)
+	vec.hashAdd = func(h uint64, s string) uint64 { return 1 }
+	vec.hashAddByte = func(h uint64, b byte) uint64 { return 1 }
+	testDeleteLabelValues(t, vec)
+}
+
+func testDeleteLabelValues(t *testing.T, vec *UntypedVec) {
+	if got, want := vec.DeleteLabelValues("v1", "v2"), false; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+
+	vec.With(Labels{"l1": "v1", "l2": "v2"}).(Untyped).Set(42)
+	vec.With(Labels{"l1": "v1", "l2": "v3"}).(Untyped).Set(42) // Add junk data for collision.
+	if got, want := vec.DeleteLabelValues("v1", "v2"), true; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+	if got, want := vec.DeleteLabelValues("v1", "v2"), false; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+	if got, want := vec.DeleteLabelValues("v1", "v3"), true; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+
+	vec.With(Labels{"l1": "v1", "l2": "v2"}).(Untyped).Set(42)
+	// Delete out of order.
+	if got, want := vec.DeleteLabelValues("v2", "v1"), false; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+	if got, want := vec.DeleteLabelValues("v1"), false; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+}
+
+func TestMetricVec(t *testing.T) {
+	vec := NewUntypedVec(
+		UntypedOpts{
+			Name: "test",
+			Help: "helpless",
+		},
+		[]string{"l1", "l2"},
+	)
+	testMetricVec(t, vec)
+}
+
+func TestMetricVecWithCollisions(t *testing.T) {
+	vec := NewUntypedVec(
+		UntypedOpts{
+			Name: "test",
+			Help: "helpless",
+		},
+		[]string{"l1", "l2"},
+	)
+	vec.hashAdd = func(h uint64, s string) uint64 { return 1 }
+	vec.hashAddByte = func(h uint64, b byte) uint64 { return 1 }
+	testMetricVec(t, vec)
+}
+
+func testMetricVec(t *testing.T, vec *UntypedVec) {
+	vec.Reset() // Actually test Reset now!
+
+	var pair [2]string
+	// Keep track of metrics.
+	expected := map[[2]string]int{}
+
+	for i := 0; i < 1000; i++ {
+		pair[0], pair[1] = fmt.Sprint(i%4), fmt.Sprint(i%5) // Varying combinations multiples.
+		expected[pair]++
+		vec.WithLabelValues(pair[0], pair[1]).Inc()
+
+		expected[[2]string{"v1", "v2"}]++
+		vec.WithLabelValues("v1", "v2").(Untyped).Inc()
+	}
+
+	var total int
+	for _, metrics := range vec.children {
+		for _, metric := range metrics {
+			total++
+			copy(pair[:], metric.values)
+
+			var metricOut dto.Metric
+			if err := metric.metric.Write(&metricOut); err != nil {
+				t.Fatal(err)
+			}
+			actual := *metricOut.Untyped.Value
+
+			var actualPair [2]string
+			for i, label := range metricOut.Label {
+				actualPair[i] = *label.Value
+			}
+
+			// Test output pair against metric.values to ensure we've selected
+			// the right one. We check this to ensure the below check means
+			// anything at all.
+			if actualPair != pair {
+				t.Fatalf("unexpected pair association in metric map: %v != %v", actualPair, pair)
+			}
+
+			if actual != float64(expected[pair]) {
+				t.Fatalf("incorrect counter value for %v: %v != %v", pair, actual, expected[pair])
+			}
+		}
+	}
+
+	if total != len(expected) {
+		t.Fatalf("unexpected number of metrics: %v != %v", total, len(expected))
+	}
+
+	vec.Reset()
+
+	if len(vec.children) > 0 {
+		t.Fatalf("reset failed")
+	}
+}
+
+func TestCounterVecEndToEndWithCollision(t *testing.T) {
+	vec := NewCounterVec(
+		CounterOpts{
+			Name: "test",
+			Help: "helpless",
+		},
+		[]string{"labelname"},
+	)
+	vec.WithLabelValues("77kepQFQ8Kl").Inc()
+	vec.WithLabelValues("!0IC=VloaY").Add(2)
+
+	m := &dto.Metric{}
+	if err := vec.WithLabelValues("77kepQFQ8Kl").Write(m); err != nil {
+		t.Fatal(err)
+	}
+	if got, want := m.GetLabel()[0].GetValue(), "77kepQFQ8Kl"; got != want {
+		t.Errorf("got label value %q, want %q", got, want)
+	}
+	if got, want := m.GetCounter().GetValue(), 1.; got != want {
+		t.Errorf("got value %f, want %f", got, want)
+	}
+	m.Reset()
+	if err := vec.WithLabelValues("!0IC=VloaY").Write(m); err != nil {
+		t.Fatal(err)
+	}
+	if got, want := m.GetLabel()[0].GetValue(), "!0IC=VloaY"; got != want {
+		t.Errorf("got label value %q, want %q", got, want)
+	}
+	if got, want := m.GetCounter().GetValue(), 2.; got != want {
+		t.Errorf("got value %f, want %f", got, want)
+	}
+}
+
+func BenchmarkMetricVecWithLabelValuesBasic(b *testing.B) {
+	benchmarkMetricVecWithLabelValues(b, map[string][]string{
+		"l1": []string{"onevalue"},
+		"l2": []string{"twovalue"},
+	})
+}
+
+func BenchmarkMetricVecWithLabelValues2Keys10ValueCardinality(b *testing.B) {
+	benchmarkMetricVecWithLabelValuesCardinality(b, 2, 10)
+}
+
+func BenchmarkMetricVecWithLabelValues4Keys10ValueCardinality(b *testing.B) {
+	benchmarkMetricVecWithLabelValuesCardinality(b, 4, 10)
+}
+
+func BenchmarkMetricVecWithLabelValues2Keys100ValueCardinality(b *testing.B) {
+	benchmarkMetricVecWithLabelValuesCardinality(b, 2, 100)
+}
+
+func BenchmarkMetricVecWithLabelValues10Keys100ValueCardinality(b *testing.B) {
+	benchmarkMetricVecWithLabelValuesCardinality(b, 10, 100)
+}
+
+func BenchmarkMetricVecWithLabelValues10Keys1000ValueCardinality(b *testing.B) {
+	benchmarkMetricVecWithLabelValuesCardinality(b, 10, 1000)
+}
+
+func benchmarkMetricVecWithLabelValuesCardinality(b *testing.B, nkeys, nvalues int) {
+	labels := map[string][]string{}
+
+	for i := 0; i < nkeys; i++ {
+		var (
+			k  = fmt.Sprintf("key-%v", i)
+			vs = make([]string, 0, nvalues)
+		)
+		for j := 0; j < nvalues; j++ {
+			vs = append(vs, fmt.Sprintf("value-%v", j))
+		}
+		labels[k] = vs
+	}
+
+	benchmarkMetricVecWithLabelValues(b, labels)
+}
+
+func benchmarkMetricVecWithLabelValues(b *testing.B, labels map[string][]string) {
+	var keys []string
+	for k := range labels { // Map order dependent, who cares though.
+		keys = append(keys, k)
+	}
+
+	values := make([]string, len(labels)) // Value cache for permutations.
+	vec := NewUntypedVec(
+		UntypedOpts{
+			Name: "test",
+			Help: "helpless",
+		},
+		keys,
+	)
+
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		// Varies input across provide map entries based on key size.
+		for j, k := range keys {
+			candidates := labels[k]
+			values[j] = candidates[i%len(candidates)]
+		}
+
+		vec.WithLabelValues(values...)
+	}
+}

vendor/github.com/prometheus/client_model/.gitignore

@@ -0,0 +1 @@
+target/

vendor/github.com/prometheus/client_model/CONTRIBUTING.md

@@ -0,0 +1,18 @@
+# Contributing
+
+Prometheus uses GitHub to manage reviews of pull requests.
+
+* If you have a trivial fix or improvement, go ahead and create a pull request,
+  addressing (with `@...`) the maintainer of this repository (see
+  [MAINTAINERS.md](MAINTAINERS.md)) in the description of the pull request.
+
+* If you plan to do something more involved, first discuss your ideas
+  on our [mailing list](https://groups.google.com/forum/?fromgroups#!forum/prometheus-developers).
+  This will avoid unnecessary work and surely give you and us a good deal
+  of inspiration.
+
+* Relevant coding style guidelines are the [Go Code Review
+  Comments](https://code.google.com/p/go-wiki/wiki/CodeReviewComments)
+  and the _Formatting and style_ section of Peter Bourgon's [Go: Best
+  Practices for Production
+  Environments](http://peter.bourgon.org/go-in-production/#formatting-and-style).

vendor/github.com/prometheus/client_model/MAINTAINERS.md

@@ -0,0 +1 @@
+* Björn Rabenstein <beorn@soundcloud.com>

vendor/github.com/prometheus/client_model/Makefile

@@ -0,0 +1,61 @@
+# Copyright 2013 Prometheus Team
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+
+# http://www.apache.org/licenses/LICENSE-2.0
+
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+KEY_ID ?= _DEFINE_ME_
+
+all: cpp go java python ruby
+
+SUFFIXES:
+
+cpp: cpp/metrics.pb.cc cpp/metrics.pb.h
+
+cpp/metrics.pb.cc: metrics.proto
+	protoc $< --cpp_out=cpp/
+
+cpp/metrics.pb.h: metrics.proto
+	protoc $< --cpp_out=cpp/
+
+go: go/metrics.pb.go
+
+go/metrics.pb.go: metrics.proto
+	protoc $< --go_out=go/
+
+java: src/main/java/io/prometheus/client/Metrics.java pom.xml
+	mvn clean compile package
+
+src/main/java/io/prometheus/client/Metrics.java: metrics.proto
+	protoc $< --java_out=src/main/java
+
+python: python/prometheus/client/model/metrics_pb2.py
+
+python/prometheus/client/model/metrics_pb2.py: metrics.proto
+	protoc $< --python_out=python/prometheus/client/model
+
+ruby:
+	$(MAKE) -C ruby build
+
+clean:
+	-rm -rf cpp/*
+	-rm -rf go/*
+	-rm -rf java/*
+	-rm -rf python/*
+	-$(MAKE) -C ruby clean
+	-mvn clean
+
+maven-deploy-snapshot: java
+	mvn clean deploy -Dgpg.keyname=$(KEY_ID) -DperformRelease=true
+
+maven-deploy-release: java
+	mvn clean release:clean release:prepare release:perform -Dgpg.keyname=$(KEY_ID) -DperformRelease=true
+
+.PHONY: all clean cpp go java maven-deploy-snapshot maven-deploy-release python ruby

vendor/github.com/prometheus/client_model/README.md

@@ -0,0 +1,26 @@
+# Background
+Under most circumstances, manually downloading this repository should never
+be required.
+
+# Prerequisites
+# Base
+* [Google Protocol Buffers](https://developers.google.com/protocol-buffers)
+
+## Java
+* [Apache Maven](http://maven.apache.org)
+* [Prometheus Maven Repository](https://github.com/prometheus/io.prometheus-maven-repository) checked out into ../io.prometheus-maven-repository
+
+## Go
+*  [Go](http://golang.org)
+*  [goprotobuf](https://code.google.com/p/goprotobuf)
+
+## Ruby
+*  [Ruby](https://www.ruby-lang.org)
+*  [bundler](https://rubygems.org/gems/bundler)
+
+# Building
+    $ make
+
+# Getting Started
+  * The Go source code is periodically indexed: [Go Protocol Buffer Model](http://godoc.org/github.com/prometheus/client_model/go).
+  * All of the core developers are accessible via the [Prometheus Developers Mailinglist](https://groups.google.com/forum/?fromgroups#!forum/prometheus-developers).

vendor/github.com/prometheus/client_model/metrics.proto

@@ -0,0 +1,81 @@
+// Copyright 2013 Prometheus Team
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+syntax = "proto2";
+
+package io.prometheus.client;
+option java_package = "io.prometheus.client";
+
+message LabelPair {
+  optional string name  = 1;
+  optional string value = 2;
+}
+
+enum MetricType {
+  COUNTER    = 0;
+  GAUGE      = 1;
+  SUMMARY    = 2;
+  UNTYPED    = 3;
+  HISTOGRAM  = 4;
+}
+
+message Gauge {
+  optional double value = 1;
+}
+
+message Counter {
+  optional double value = 1;
+}
+
+message Quantile {
+  optional double quantile = 1;
+  optional double value    = 2;
+}
+
+message Summary {
+  optional uint64   sample_count = 1;
+  optional double   sample_sum   = 2;
+  repeated Quantile quantile     = 3;
+}
+
+message Untyped {
+  optional double value = 1;
+}
+
+message Histogram {
+  optional uint64 sample_count = 1;
+  optional double sample_sum   = 2;
+  repeated Bucket bucket       = 3; // Ordered in increasing order of upper_bound, +Inf bucket is optional.
+}
+
+message Bucket {
+  optional uint64 cumulative_count = 1; // Cumulative in increasing order.
+  optional double upper_bound = 2;      // Inclusive.
+}
+
+message Metric {
+  repeated LabelPair label        = 1;
+  optional Gauge     gauge        = 2;
+  optional Counter   counter      = 3;
+  optional Summary   summary      = 4;
+  optional Untyped   untyped      = 5;
+  optional Histogram histogram    = 7;
+  optional int64     timestamp_ms = 6;
+}
+
+message MetricFamily {
+  optional string     name   = 1;
+  optional string     help   = 2;
+  optional MetricType type   = 3;
+  repeated Metric     metric = 4;
+}

vendor/github.com/prometheus/client_model/pom.xml

@@ -0,0 +1,130 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>io.prometheus.client</groupId>
+    <artifactId>model</artifactId>
+    <version>0.0.3-SNAPSHOT</version>
+
+    <parent>
+        <groupId>org.sonatype.oss</groupId>
+        <artifactId>oss-parent</artifactId>
+        <version>7</version>
+    </parent>
+
+    <name>Prometheus Client Data Model</name>
+    <url>http://github.com/prometheus/client_model</url>
+    <description>
+      Prometheus Client Data Model: Generated Protocol Buffer Assets
+    </description>
+
+    <licenses>
+        <license>
+            <name>The Apache Software License, Version 2.0</name>
+            <url>http://www.apache.org/licenses/LICENSE-2.0.txt</url>
+            <distribution>repo</distribution>
+        </license>
+    </licenses>
+
+    <scm>
+        <connection>scm:git:git@github.com:prometheus/client_model.git</connection>
+        <developerConnection>scm:git:git@github.com:prometheus/client_model.git</developerConnection>
+        <url>git@github.com:prometheus/client_model.git</url>
+    </scm>
+
+    <developers>
+        <developer>
+            <id>mtp</id>
+            <name>Matt T. Proud</name>
+            <email>matt.proud@gmail.com</email>
+        </developer>
+    </developers>
+
+    <dependencies>
+      <dependency>
+        <groupId>com.google.protobuf</groupId>
+        <artifactId>protobuf-java</artifactId>
+        <version>2.5.0</version>
+      </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-javadoc-plugin</artifactId>
+                <version>2.8</version>
+                <configuration>
+                    <encoding>UTF-8</encoding>
+                    <docencoding>UTF-8</docencoding>
+                    <linksource>true</linksource>
+                </configuration>
+                <executions>
+                    <execution>
+                        <id>generate-javadoc-site-report</id>
+                        <phase>site</phase>
+                        <goals>
+                            <goal>javadoc</goal>
+                        </goals>
+                    </execution>
+                    <execution>
+                      <id>attach-javadocs</id>
+                      <goals>
+                        <goal>jar</goal>
+                      </goals>
+                    </execution>
+                </executions>
+            </plugin>
+            <plugin>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>1.6</source>
+                    <target>1.6</target>
+                </configuration>
+                <version>3.1</version>
+            </plugin>
+            <plugin>
+              <groupId>org.apache.maven.plugins</groupId>
+              <artifactId>maven-source-plugin</artifactId>
+              <version>2.2.1</version>
+              <executions>
+                <execution>
+                  <id>attach-sources</id>
+                  <goals>
+                    <goal>jar</goal>
+                  </goals>
+                </execution>
+              </executions>
+            </plugin>
+        </plugins>
+    </build>
+    <profiles>
+        <profile>
+            <id>release-sign-artifacts</id>
+            <activation>
+                <property>
+                    <name>performRelease</name>
+                    <value>true</value>
+                </property>
+            </activation>
+            <build>
+                <plugins>
+                    <plugin>
+                        <groupId>org.apache.maven.plugins</groupId>
+                        <artifactId>maven-gpg-plugin</artifactId>
+                        <version>1.4</version>
+                        <executions>
+                            <execution>
+                                <id>sign-artifacts</id>
+                                <phase>verify</phase>
+                                <goals>
+                                    <goal>sign</goal>
+                                </goals>
+                            </execution>
+                        </executions>
+                    </plugin>
+                </plugins>
+            </build>
+        </profile>
+    </profiles>
+</project>

vendor/github.com/prometheus/client_model/python/prometheus/__init__.py

@@ -0,0 +1,12 @@
+ # Copyright 2013 Prometheus Team
+ # Licensed under the Apache License, Version 2.0 (the "License");
+ # you may not use this file except in compliance with the License.
+ # You may obtain a copy of the License at
+
+ # http://www.apache.org/licenses/LICENSE-2.0
+
+ # Unless required by applicable law or agreed to in writing, software
+ # distributed under the License is distributed on an "AS IS" BASIS,
+ # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ # See the License for the specific language governing permissions and
+ # limitations under the License.

vendor/github.com/prometheus/client_model/python/prometheus/client/__init__.py

@@ -0,0 +1,12 @@
+ # Copyright 2013 Prometheus Team
+ # Licensed under the Apache License, Version 2.0 (the "License");
+ # you may not use this file except in compliance with the License.
+ # You may obtain a copy of the License at
+
+ # http://www.apache.org/licenses/LICENSE-2.0
+
+ # Unless required by applicable law or agreed to in writing, software
+ # distributed under the License is distributed on an "AS IS" BASIS,
+ # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ # See the License for the specific language governing permissions and
+ # limitations under the License.

vendor/github.com/prometheus/client_model/python/prometheus/client/model/__init__.py

@@ -0,0 +1,14 @@
+ # Copyright 2013 Prometheus Team
+ # Licensed under the Apache License, Version 2.0 (the "License");
+ # you may not use this file except in compliance with the License.
+ # You may obtain a copy of the License at
+
+ # http://www.apache.org/licenses/LICENSE-2.0
+
+ # Unless required by applicable law or agreed to in writing, software
+ # distributed under the License is distributed on an "AS IS" BASIS,
+ # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ # See the License for the specific language governing permissions and
+ # limitations under the License.
+
+__all__ = ['metrics_pb2']

vendor/github.com/prometheus/client_model/python/prometheus/client/model/metrics_pb2.py

@@ -0,0 +1,575 @@
+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# source: metrics.proto
+
+import sys
+_b=sys.version_info[0]<3 and (lambda x:x) or (lambda x:x.encode('latin1'))
+from google.protobuf.internal import enum_type_wrapper
+from google.protobuf import descriptor as _descriptor
+from google.protobuf import message as _message
+from google.protobuf import reflection as _reflection
+from google.protobuf import symbol_database as _symbol_database
+from google.protobuf import descriptor_pb2
+# @@protoc_insertion_point(imports)
+
+_sym_db = _symbol_database.Default()
+
+
+
+
+DESCRIPTOR = _descriptor.FileDescriptor(
+  name='metrics.proto',
+  package='io.prometheus.client',
+  serialized_pb=_b('\n\rmetrics.proto\x12\x14io.prometheus.client\"(\n\tLabelPair\x12\x0c\n\x04name\x18\x01 \x01(\t\x12\r\n\x05value\x18\x02 \x01(\t\"\x16\n\x05Gauge\x12\r\n\x05value\x18\x01 \x01(\x01\"\x18\n\x07\x43ounter\x12\r\n\x05value\x18\x01 \x01(\x01\"+\n\x08Quantile\x12\x10\n\x08quantile\x18\x01 \x01(\x01\x12\r\n\x05value\x18\x02 \x01(\x01\"e\n\x07Summary\x12\x14\n\x0csample_count\x18\x01 \x01(\x04\x12\x12\n\nsample_sum\x18\x02 \x01(\x01\x12\x30\n\x08quantile\x18\x03 \x03(\x0b\x32\x1e.io.prometheus.client.Quantile\"\x18\n\x07Untyped\x12\r\n\x05value\x18\x01 \x01(\x01\"c\n\tHistogram\x12\x14\n\x0csample_count\x18\x01 \x01(\x04\x12\x12\n\nsample_sum\x18\x02 \x01(\x01\x12,\n\x06\x62ucket\x18\x03 \x03(\x0b\x32\x1c.io.prometheus.client.Bucket\"7\n\x06\x42ucket\x12\x18\n\x10\x63umulative_count\x18\x01 \x01(\x04\x12\x13\n\x0bupper_bound\x18\x02 \x01(\x01\"\xbe\x02\n\x06Metric\x12.\n\x05label\x18\x01 \x03(\x0b\x32\x1f.io.prometheus.client.LabelPair\x12*\n\x05gauge\x18\x02 \x01(\x0b\x32\x1b.io.prometheus.client.Gauge\x12.\n\x07\x63ounter\x18\x03 \x01(\x0b\x32\x1d.io.prometheus.client.Counter\x12.\n\x07summary\x18\x04 \x01(\x0b\x32\x1d.io.prometheus.client.Summary\x12.\n\x07untyped\x18\x05 \x01(\x0b\x32\x1d.io.prometheus.client.Untyped\x12\x32\n\thistogram\x18\x07 \x01(\x0b\x32\x1f.io.prometheus.client.Histogram\x12\x14\n\x0ctimestamp_ms\x18\x06 \x01(\x03\"\x88\x01\n\x0cMetricFamily\x12\x0c\n\x04name\x18\x01 \x01(\t\x12\x0c\n\x04help\x18\x02 \x01(\t\x12.\n\x04type\x18\x03 \x01(\x0e\x32 .io.prometheus.client.MetricType\x12,\n\x06metric\x18\x04 \x03(\x0b\x32\x1c.io.prometheus.client.Metric*M\n\nMetricType\x12\x0b\n\x07\x43OUNTER\x10\x00\x12\t\n\x05GAUGE\x10\x01\x12\x0b\n\x07SUMMARY\x10\x02\x12\x0b\n\x07UNTYPED\x10\x03\x12\r\n\tHISTOGRAM\x10\x04\x42\x16\n\x14io.prometheus.client')
+)
+_sym_db.RegisterFileDescriptor(DESCRIPTOR)
+
+_METRICTYPE = _descriptor.EnumDescriptor(
+  name='MetricType',
+  full_name='io.prometheus.client.MetricType',
+  filename=None,
+  file=DESCRIPTOR,
+  values=[
+    _descriptor.EnumValueDescriptor(
+      name='COUNTER', index=0, number=0,
+      options=None,
+      type=None),
+    _descriptor.EnumValueDescriptor(
+      name='GAUGE', index=1, number=1,
+      options=None,
+      type=None),
+    _descriptor.EnumValueDescriptor(
+      name='SUMMARY', index=2, number=2,
+      options=None,
+      type=None),
+    _descriptor.EnumValueDescriptor(
+      name='UNTYPED', index=3, number=3,
+      options=None,
+      type=None),
+    _descriptor.EnumValueDescriptor(
+      name='HISTOGRAM', index=4, number=4,
+      options=None,
+      type=None),
+  ],
+  containing_type=None,
+  options=None,
+  serialized_start=923,
+  serialized_end=1000,
+)
+_sym_db.RegisterEnumDescriptor(_METRICTYPE)
+
+MetricType = enum_type_wrapper.EnumTypeWrapper(_METRICTYPE)
+COUNTER = 0
+GAUGE = 1
+SUMMARY = 2
+UNTYPED = 3
+HISTOGRAM = 4
+
+
+
+_LABELPAIR = _descriptor.Descriptor(
+  name='LabelPair',
+  full_name='io.prometheus.client.LabelPair',
+  filename=None,
+  file=DESCRIPTOR,
+  containing_type=None,
+  fields=[
+    _descriptor.FieldDescriptor(
+      name='name', full_name='io.prometheus.client.LabelPair.name', index=0,
+      number=1, type=9, cpp_type=9, label=1,
+      has_default_value=False, default_value=_b("").decode('utf-8'),
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='value', full_name='io.prometheus.client.LabelPair.value', index=1,
+      number=2, type=9, cpp_type=9, label=1,
+      has_default_value=False, default_value=_b("").decode('utf-8'),
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+  ],
+  extensions=[
+  ],
+  nested_types=[],
+  enum_types=[
+  ],
+  options=None,
+  is_extendable=False,
+  extension_ranges=[],
+  oneofs=[
+  ],
+  serialized_start=39,
+  serialized_end=79,
+)
+
+
+_GAUGE = _descriptor.Descriptor(
+  name='Gauge',
+  full_name='io.prometheus.client.Gauge',
+  filename=None,
+  file=DESCRIPTOR,
+  containing_type=None,
+  fields=[
+    _descriptor.FieldDescriptor(
+      name='value', full_name='io.prometheus.client.Gauge.value', index=0,
+      number=1, type=1, cpp_type=5, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+  ],
+  extensions=[
+  ],
+  nested_types=[],
+  enum_types=[
+  ],
+  options=None,
+  is_extendable=False,
+  extension_ranges=[],
+  oneofs=[
+  ],
+  serialized_start=81,
+  serialized_end=103,
+)
+
+
+_COUNTER = _descriptor.Descriptor(
+  name='Counter',
+  full_name='io.prometheus.client.Counter',
+  filename=None,
+  file=DESCRIPTOR,
+  containing_type=None,
+  fields=[
+    _descriptor.FieldDescriptor(
+      name='value', full_name='io.prometheus.client.Counter.value', index=0,
+      number=1, type=1, cpp_type=5, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+  ],
+  extensions=[
+  ],
+  nested_types=[],
+  enum_types=[
+  ],
+  options=None,
+  is_extendable=False,
+  extension_ranges=[],
+  oneofs=[
+  ],
+  serialized_start=105,
+  serialized_end=129,
+)
+
+
+_QUANTILE = _descriptor.Descriptor(
+  name='Quantile',
+  full_name='io.prometheus.client.Quantile',
+  filename=None,
+  file=DESCRIPTOR,
+  containing_type=None,
+  fields=[
+    _descriptor.FieldDescriptor(
+      name='quantile', full_name='io.prometheus.client.Quantile.quantile', index=0,
+      number=1, type=1, cpp_type=5, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='value', full_name='io.prometheus.client.Quantile.value', index=1,
+      number=2, type=1, cpp_type=5, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+  ],
+  extensions=[
+  ],
+  nested_types=[],
+  enum_types=[
+  ],
+  options=None,
+  is_extendable=False,
+  extension_ranges=[],
+  oneofs=[
+  ],
+  serialized_start=131,
+  serialized_end=174,
+)
+
+
+_SUMMARY = _descriptor.Descriptor(
+  name='Summary',
+  full_name='io.prometheus.client.Summary',
+  filename=None,
+  file=DESCRIPTOR,
+  containing_type=None,
+  fields=[
+    _descriptor.FieldDescriptor(
+      name='sample_count', full_name='io.prometheus.client.Summary.sample_count', index=0,
+      number=1, type=4, cpp_type=4, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='sample_sum', full_name='io.prometheus.client.Summary.sample_sum', index=1,
+      number=2, type=1, cpp_type=5, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='quantile', full_name='io.prometheus.client.Summary.quantile', index=2,
+      number=3, type=11, cpp_type=10, label=3,
+      has_default_value=False, default_value=[],
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+  ],
+  extensions=[
+  ],
+  nested_types=[],
+  enum_types=[
+  ],
+  options=None,
+  is_extendable=False,
+  extension_ranges=[],
+  oneofs=[
+  ],
+  serialized_start=176,
+  serialized_end=277,
+)
+
+
+_UNTYPED = _descriptor.Descriptor(
+  name='Untyped',
+  full_name='io.prometheus.client.Untyped',
+  filename=None,
+  file=DESCRIPTOR,
+  containing_type=None,
+  fields=[
+    _descriptor.FieldDescriptor(
+      name='value', full_name='io.prometheus.client.Untyped.value', index=0,
+      number=1, type=1, cpp_type=5, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+  ],
+  extensions=[
+  ],
+  nested_types=[],
+  enum_types=[
+  ],
+  options=None,
+  is_extendable=False,
+  extension_ranges=[],
+  oneofs=[
+  ],
+  serialized_start=279,
+  serialized_end=303,
+)
+
+
+_HISTOGRAM = _descriptor.Descriptor(
+  name='Histogram',
+  full_name='io.prometheus.client.Histogram',
+  filename=None,
+  file=DESCRIPTOR,
+  containing_type=None,
+  fields=[
+    _descriptor.FieldDescriptor(
+      name='sample_count', full_name='io.prometheus.client.Histogram.sample_count', index=0,
+      number=1, type=4, cpp_type=4, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='sample_sum', full_name='io.prometheus.client.Histogram.sample_sum', index=1,
+      number=2, type=1, cpp_type=5, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='bucket', full_name='io.prometheus.client.Histogram.bucket', index=2,
+      number=3, type=11, cpp_type=10, label=3,
+      has_default_value=False, default_value=[],
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+  ],
+  extensions=[
+  ],
+  nested_types=[],
+  enum_types=[
+  ],
+  options=None,
+  is_extendable=False,
+  extension_ranges=[],
+  oneofs=[
+  ],
+  serialized_start=305,
+  serialized_end=404,
+)
+
+
+_BUCKET = _descriptor.Descriptor(
+  name='Bucket',
+  full_name='io.prometheus.client.Bucket',
+  filename=None,
+  file=DESCRIPTOR,
+  containing_type=None,
+  fields=[
+    _descriptor.FieldDescriptor(
+      name='cumulative_count', full_name='io.prometheus.client.Bucket.cumulative_count', index=0,
+      number=1, type=4, cpp_type=4, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='upper_bound', full_name='io.prometheus.client.Bucket.upper_bound', index=1,
+      number=2, type=1, cpp_type=5, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+  ],
+  extensions=[
+  ],
+  nested_types=[],
+  enum_types=[
+  ],
+  options=None,
+  is_extendable=False,
+  extension_ranges=[],
+  oneofs=[
+  ],
+  serialized_start=406,
+  serialized_end=461,
+)
+
+
+_METRIC = _descriptor.Descriptor(
+  name='Metric',
+  full_name='io.prometheus.client.Metric',
+  filename=None,
+  file=DESCRIPTOR,
+  containing_type=None,
+  fields=[
+    _descriptor.FieldDescriptor(
+      name='label', full_name='io.prometheus.client.Metric.label', index=0,
+      number=1, type=11, cpp_type=10, label=3,
+      has_default_value=False, default_value=[],
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='gauge', full_name='io.prometheus.client.Metric.gauge', index=1,
+      number=2, type=11, cpp_type=10, label=1,
+      has_default_value=False, default_value=None,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='counter', full_name='io.prometheus.client.Metric.counter', index=2,
+      number=3, type=11, cpp_type=10, label=1,
+      has_default_value=False, default_value=None,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='summary', full_name='io.prometheus.client.Metric.summary', index=3,
+      number=4, type=11, cpp_type=10, label=1,
+      has_default_value=False, default_value=None,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='untyped', full_name='io.prometheus.client.Metric.untyped', index=4,
+      number=5, type=11, cpp_type=10, label=1,
+      has_default_value=False, default_value=None,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='histogram', full_name='io.prometheus.client.Metric.histogram', index=5,
+      number=7, type=11, cpp_type=10, label=1,
+      has_default_value=False, default_value=None,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='timestamp_ms', full_name='io.prometheus.client.Metric.timestamp_ms', index=6,
+      number=6, type=3, cpp_type=2, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+  ],
+  extensions=[
+  ],
+  nested_types=[],
+  enum_types=[
+  ],
+  options=None,
+  is_extendable=False,
+  extension_ranges=[],
+  oneofs=[
+  ],
+  serialized_start=464,
+  serialized_end=782,
+)
+
+
+_METRICFAMILY = _descriptor.Descriptor(
+  name='MetricFamily',
+  full_name='io.prometheus.client.MetricFamily',
+  filename=None,
+  file=DESCRIPTOR,
+  containing_type=None,
+  fields=[
+    _descriptor.FieldDescriptor(
+      name='name', full_name='io.prometheus.client.MetricFamily.name', index=0,
+      number=1, type=9, cpp_type=9, label=1,
+      has_default_value=False, default_value=_b("").decode('utf-8'),
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='help', full_name='io.prometheus.client.MetricFamily.help', index=1,
+      number=2, type=9, cpp_type=9, label=1,
+      has_default_value=False, default_value=_b("").decode('utf-8'),
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='type', full_name='io.prometheus.client.MetricFamily.type', index=2,
+      number=3, type=14, cpp_type=8, label=1,
+      has_default_value=False, default_value=0,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+    _descriptor.FieldDescriptor(
+      name='metric', full_name='io.prometheus.client.MetricFamily.metric', index=3,
+      number=4, type=11, cpp_type=10, label=3,
+      has_default_value=False, default_value=[],
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
+  ],
+  extensions=[
+  ],
+  nested_types=[],
+  enum_types=[
+  ],
+  options=None,
+  is_extendable=False,
+  extension_ranges=[],
+  oneofs=[
+  ],
+  serialized_start=785,
+  serialized_end=921,
+)
+
+_SUMMARY.fields_by_name['quantile'].message_type = _QUANTILE
+_HISTOGRAM.fields_by_name['bucket'].message_type = _BUCKET
+_METRIC.fields_by_name['label'].message_type = _LABELPAIR
+_METRIC.fields_by_name['gauge'].message_type = _GAUGE
+_METRIC.fields_by_name['counter'].message_type = _COUNTER
+_METRIC.fields_by_name['summary'].message_type = _SUMMARY
+_METRIC.fields_by_name['untyped'].message_type = _UNTYPED
+_METRIC.fields_by_name['histogram'].message_type = _HISTOGRAM
+_METRICFAMILY.fields_by_name['type'].enum_type = _METRICTYPE
+_METRICFAMILY.fields_by_name['metric'].message_type = _METRIC
+DESCRIPTOR.message_types_by_name['LabelPair'] = _LABELPAIR
+DESCRIPTOR.message_types_by_name['Gauge'] = _GAUGE
+DESCRIPTOR.message_types_by_name['Counter'] = _COUNTER
+DESCRIPTOR.message_types_by_name['Quantile'] = _QUANTILE
+DESCRIPTOR.message_types_by_name['Summary'] = _SUMMARY
+DESCRIPTOR.message_types_by_name['Untyped'] = _UNTYPED
+DESCRIPTOR.message_types_by_name['Histogram'] = _HISTOGRAM
+DESCRIPTOR.message_types_by_name['Bucket'] = _BUCKET
+DESCRIPTOR.message_types_by_name['Metric'] = _METRIC
+DESCRIPTOR.message_types_by_name['MetricFamily'] = _METRICFAMILY
+DESCRIPTOR.enum_types_by_name['MetricType'] = _METRICTYPE
+
+LabelPair = _reflection.GeneratedProtocolMessageType('LabelPair', (_message.Message,), dict(
+  DESCRIPTOR = _LABELPAIR,
+  __module__ = 'metrics_pb2'
+  # @@protoc_insertion_point(class_scope:io.prometheus.client.LabelPair)
+  ))
+_sym_db.RegisterMessage(LabelPair)
+
+Gauge = _reflection.GeneratedProtocolMessageType('Gauge', (_message.Message,), dict(
+  DESCRIPTOR = _GAUGE,
+  __module__ = 'metrics_pb2'
+  # @@protoc_insertion_point(class_scope:io.prometheus.client.Gauge)
+  ))
+_sym_db.RegisterMessage(Gauge)
+
+Counter = _reflection.GeneratedProtocolMessageType('Counter', (_message.Message,), dict(
+  DESCRIPTOR = _COUNTER,
+  __module__ = 'metrics_pb2'
+  # @@protoc_insertion_point(class_scope:io.prometheus.client.Counter)
+  ))
+_sym_db.RegisterMessage(Counter)
+
+Quantile = _reflection.GeneratedProtocolMessageType('Quantile', (_message.Message,), dict(
+  DESCRIPTOR = _QUANTILE,
+  __module__ = 'metrics_pb2'
+  # @@protoc_insertion_point(class_scope:io.prometheus.client.Quantile)
+  ))
+_sym_db.RegisterMessage(Quantile)
+
+Summary = _reflection.GeneratedProtocolMessageType('Summary', (_message.Message,), dict(
+  DESCRIPTOR = _SUMMARY,
+  __module__ = 'metrics_pb2'
+  # @@protoc_insertion_point(class_scope:io.prometheus.client.Summary)
+  ))
+_sym_db.RegisterMessage(Summary)
+
+Untyped = _reflection.GeneratedProtocolMessageType('Untyped', (_message.Message,), dict(
+  DESCRIPTOR = _UNTYPED,
+  __module__ = 'metrics_pb2'
+  # @@protoc_insertion_point(class_scope:io.prometheus.client.Untyped)
+  ))
+_sym_db.RegisterMessage(Untyped)
+
+Histogram = _reflection.GeneratedProtocolMessageType('Histogram', (_message.Message,), dict(
+  DESCRIPTOR = _HISTOGRAM,
+  __module__ = 'metrics_pb2'
+  # @@protoc_insertion_point(class_scope:io.prometheus.client.Histogram)
+  ))
+_sym_db.RegisterMessage(Histogram)
+
+Bucket = _reflection.GeneratedProtocolMessageType('Bucket', (_message.Message,), dict(
+  DESCRIPTOR = _BUCKET,
+  __module__ = 'metrics_pb2'
+  # @@protoc_insertion_point(class_scope:io.prometheus.client.Bucket)
+  ))
+_sym_db.RegisterMessage(Bucket)
+
+Metric = _reflection.GeneratedProtocolMessageType('Metric', (_message.Message,), dict(
+  DESCRIPTOR = _METRIC,
+  __module__ = 'metrics_pb2'
+  # @@protoc_insertion_point(class_scope:io.prometheus.client.Metric)
+  ))
+_sym_db.RegisterMessage(Metric)
+
+MetricFamily = _reflection.GeneratedProtocolMessageType('MetricFamily', (_message.Message,), dict(
+  DESCRIPTOR = _METRICFAMILY,
+  __module__ = 'metrics_pb2'
+  # @@protoc_insertion_point(class_scope:io.prometheus.client.MetricFamily)
+  ))
+_sym_db.RegisterMessage(MetricFamily)
+
+
+DESCRIPTOR.has_options = True
+DESCRIPTOR._options = _descriptor._ParseOptions(descriptor_pb2.FileOptions(), _b('\n\024io.prometheus.client'))
+# @@protoc_insertion_point(module_scope)

vendor/github.com/prometheus/client_model/ruby/.gitignore

@@ -0,0 +1,5 @@
+*.gem
+.bundle
+Gemfile.lock
+pkg
+vendor/bundle

vendor/github.com/prometheus/client_model/ruby/Gemfile

@@ -0,0 +1,4 @@
+source 'https://rubygems.org'
+
+# Specify your gem's dependencies in prometheus-client-model.gemspec
+gemspec

vendor/github.com/prometheus/client_model/ruby/LICENSE

@@ -0,0 +1,201 @@
+                              Apache License
+                        Version 2.0, January 2004
+                     http://www.apache.org/licenses/
+
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+1. Definitions.
+
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+   otherwise, or (ii) ownership of fifty percent (50%) or more of the
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+   and charge a fee for, acceptance of support, warranty, indemnity,
+   or other liability obligations and/or rights consistent with this
+   License. However, in accepting such obligations, You may act only
+   on Your own behalf and on Your sole responsibility, not on behalf
+   of any other Contributor, and only if You agree to indemnify,
+   defend, and hold each Contributor harmless for any liability
+   incurred by, or claims asserted against, such Contributor by reason
+   of your accepting any such warranty or additional liability.
+
+END OF TERMS AND CONDITIONS
+
+APPENDIX: How to apply the Apache License to your work.
+
+   To apply the Apache License to your work, attach the following
+   boilerplate notice, with the fields enclosed by brackets "[]"
+   replaced with your own identifying information. (Don't include
+   the brackets!)  The text should be enclosed in the appropriate
+   comment syntax for the file format. We also recommend that a
+   file or class name and description of purpose be included on the
+   same "printed page" as the copyright notice for easier
+   identification within third-party archives.
+
+Copyright [yyyy] [name of copyright owner]
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

vendor/github.com/prometheus/client_model/ruby/Makefile

@@ -0,0 +1,17 @@
+VENDOR_BUNDLE = vendor/bundle
+
+build: $(VENDOR_BUNDLE)/.bundled
+	BEEFCAKE_NAMESPACE=Prometheus::Client protoc --beefcake_out lib/prometheus/client/model -I .. ../metrics.proto
+
+$(VENDOR_BUNDLE):
+	mkdir -p $@
+
+$(VENDOR_BUNDLE)/.bundled: $(VENDOR_BUNDLE) Gemfile
+	bundle install --quiet --path $<
+	@touch $@
+
+clean:
+	-rm -f lib/prometheus/client/model/metrics.pb.rb
+	-rm -rf $(VENDOR_BUNDLE)
+
+.PHONY: build clean

vendor/github.com/prometheus/client_model/ruby/README.md

@@ -0,0 +1,31 @@
+# Prometheus Ruby client model
+
+Data model artifacts for the [Prometheus Ruby client][1].
+
+## Installation
+
+    gem install prometheus-client-model
+
+## Usage
+
+Build the artifacts from the protobuf specification:
+
+    make build
+
+While this Gem's main purpose is to define the Prometheus data types for the
+[client][1], it's possible to use it without the client to decode a stream of
+delimited protobuf messages:
+
+```ruby
+require 'open-uri'
+require 'prometheus/client/model'
+
+CONTENT_TYPE = 'application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=delimited'
+
+stream = open('http://localhost:9090/metrics', 'Accept' => CONTENT_TYPE).read
+while family = Prometheus::Client::MetricFamily.read_delimited(stream)
+  puts family
+end
+```
+
+[1]: https://github.com/prometheus/client_ruby

vendor/github.com/prometheus/client_model/ruby/Rakefile

@@ -0,0 +1 @@
+require "bundler/gem_tasks"

vendor/github.com/prometheus/client_model/ruby/lib/prometheus/client/model.rb

@@ -0,0 +1,2 @@
+require 'prometheus/client/model/metrics.pb'
+require 'prometheus/client/model/version'

vendor/github.com/prometheus/client_model/ruby/lib/prometheus/client/model/metrics.pb.rb

@@ -0,0 +1,111 @@
+## Generated from metrics.proto for io.prometheus.client
+require "beefcake"
+
+module Prometheus
+  module Client
+
+    module MetricType
+      COUNTER = 0
+      GAUGE = 1
+      SUMMARY = 2
+      UNTYPED = 3
+      HISTOGRAM = 4
+    end
+
+    class LabelPair
+      include Beefcake::Message
+    end
+
+    class Gauge
+      include Beefcake::Message
+    end
+
+    class Counter
+      include Beefcake::Message
+    end
+
+    class Quantile
+      include Beefcake::Message
+    end
+
+    class Summary
+      include Beefcake::Message
+    end
+
+    class Untyped
+      include Beefcake::Message
+    end
+
+    class Histogram
+      include Beefcake::Message
+    end
+
+    class Bucket
+      include Beefcake::Message
+    end
+
+    class Metric
+      include Beefcake::Message
+    end
+
+    class MetricFamily
+      include Beefcake::Message
+    end
+
+    class LabelPair
+      optional :name, :string, 1
+      optional :value, :string, 2
+    end
+
+    class Gauge
+      optional :value, :double, 1
+    end
+
+    class Counter
+      optional :value, :double, 1
+    end
+
+    class Quantile
+      optional :quantile, :double, 1
+      optional :value, :double, 2
+    end
+
+    class Summary
+      optional :sample_count, :uint64, 1
+      optional :sample_sum, :double, 2
+      repeated :quantile, Quantile, 3
+    end
+
+    class Untyped
+      optional :value, :double, 1
+    end
+
+    class Histogram
+      optional :sample_count, :uint64, 1
+      optional :sample_sum, :double, 2
+      repeated :bucket, Bucket, 3
+    end
+
+    class Bucket
+      optional :cumulative_count, :uint64, 1
+      optional :upper_bound, :double, 2
+    end
+
+    class Metric
+      repeated :label, LabelPair, 1
+      optional :gauge, Gauge, 2
+      optional :counter, Counter, 3
+      optional :summary, Summary, 4
+      optional :untyped, Untyped, 5
+      optional :histogram, Histogram, 7
+      optional :timestamp_ms, :int64, 6
+    end
+
+    class MetricFamily
+      optional :name, :string, 1
+      optional :help, :string, 2
+      optional :type, MetricType, 3
+      repeated :metric, Metric, 4
+    end
+  end
+end

vendor/github.com/prometheus/client_model/ruby/lib/prometheus/client/model/version.rb

@@ -0,0 +1,7 @@
+module Prometheus
+  module Client
+    module Model
+      VERSION = '0.1.0'
+    end
+  end
+end

vendor/github.com/prometheus/client_model/ruby/prometheus-client-model.gemspec

@@ -0,0 +1,22 @@
+# coding: utf-8
+lib = File.expand_path('../lib', __FILE__)
+$LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
+require 'prometheus/client/model/version'
+
+Gem::Specification.new do |spec|
+  spec.name          = 'prometheus-client-model'
+  spec.version       = Prometheus::Client::Model::VERSION
+  spec.authors       = ['Tobias Schmidt']
+  spec.email         = ['tobidt@gmail.com']
+  spec.summary       = 'Data model artifacts for the Prometheus Ruby client'
+  spec.homepage      = 'https://github.com/prometheus/client_model/tree/master/ruby'
+  spec.license       = 'Apache 2.0'
+
+  spec.files         = %w[README.md LICENSE] + Dir.glob('{lib/**/*}')
+  spec.require_paths = ['lib']
+
+  spec.add_dependency 'beefcake', '>= 0.4.0'
+
+  spec.add_development_dependency 'bundler', '~> 1.3'
+  spec.add_development_dependency 'rake'
+end

vendor/github.com/prometheus/client_model/setup.py

@@ -0,0 +1,23 @@
+#!/usr/bin/python
+
+from setuptools import setup
+
+setup(
+    name = 'prometheus_client_model',
+    version = '0.0.1',
+    author = 'Matt T. Proud',
+    author_email = 'matt.proud@gmail.com',
+    description = 'Data model artifacts for the Prometheus client.',
+    license = 'Apache License 2.0',
+    url = 'http://github.com/prometheus/client_model',
+    packages = ['prometheus', 'prometheus/client', 'prometheus/client/model'],
+    package_dir = {'': 'python'},
+    requires = ['protobuf(==2.4.1)'],
+    platforms = 'Platform Independent',
+    classifiers = ['Development Status :: 3 - Alpha',
+                   'Intended Audience :: Developers',
+                   'Intended Audience :: System Administrators',
+                   'License :: OSI Approved :: Apache Software License',
+                   'Operating System :: OS Independent',
+                   'Topic :: Software Development :: Testing',
+                   'Topic :: System :: Monitoring'])

vendor/github.com/prometheus/common/.travis.yml

@@ -0,0 +1,6 @@
+sudo: false
+
+language: go
+go:
+  - 1.7.5
+  - tip

vendor/github.com/prometheus/common/CONTRIBUTING.md

@@ -0,0 +1,18 @@
+# Contributing
+
+Prometheus uses GitHub to manage reviews of pull requests.
+
+* If you have a trivial fix or improvement, go ahead and create a pull request,
+  addressing (with `@...`) the maintainer of this repository (see
+  [MAINTAINERS.md](MAINTAINERS.md)) in the description of the pull request.
+
+* If you plan to do something more involved, first discuss your ideas
+  on our [mailing list](https://groups.google.com/forum/?fromgroups#!forum/prometheus-developers).
+  This will avoid unnecessary work and surely give you and us a good deal
+  of inspiration.
+
+* Relevant coding style guidelines are the [Go Code Review
+  Comments](https://code.google.com/p/go-wiki/wiki/CodeReviewComments)
+  and the _Formatting and style_ section of Peter Bourgon's [Go: Best
+  Practices for Production
+  Environments](http://peter.bourgon.org/go-in-production/#formatting-and-style).

vendor/github.com/prometheus/common/MAINTAINERS.md

@@ -0,0 +1 @@
+* Fabian Reinartz <fabian.reinartz@coreos.com>

vendor/github.com/prometheus/common/README.md

@@ -0,0 +1,12 @@
+# Common
+[![Build Status](https://travis-ci.org/prometheus/common.svg)](https://travis-ci.org/prometheus/common)
+
+This repository contains Go libraries that are shared across Prometheus
+components and libraries.
+
+* **config**: Common configuration structures
+* **expfmt**: Decoding and encoding for the exposition format
+* **log**: A logging wrapper around [logrus](https://github.com/sirupsen/logrus)
+* **model**: Shared data structures
+* **route**: A routing wrapper around [httprouter](https://github.com/julienschmidt/httprouter) using `context.Context`
+* **version**: Version informations and metric

vendor/github.com/prometheus/common/config/config.go

@@ -0,0 +1,47 @@
+// Copyright 2016 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package config
+
+import (
+	"fmt"
+	"strings"
+)
+
+func checkOverflow(m map[string]interface{}, ctx string) error {
+	if len(m) > 0 {
+		var keys []string
+		for k := range m {
+			keys = append(keys, k)
+		}
+		return fmt.Errorf("unknown fields in %s: %s", ctx, strings.Join(keys, ", "))
+	}
+	return nil
+}
+
+// Secret special type for storing secrets.
+type Secret string
+
+// MarshalYAML implements the yaml.Marshaler interface for Secrets.
+func (s Secret) MarshalYAML() (interface{}, error) {
+	if s != "" {
+		return "<secret>", nil
+	}
+	return nil, nil
+}
+
+//UnmarshalYAML implements the yaml.Unmarshaler interface for Secrets.
+func (s *Secret) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	type plain Secret
+	return unmarshal((*plain)(s))
+}

vendor/github.com/prometheus/common/config/http_config.go

@@ -0,0 +1,279 @@
+// Copyright 2016 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package config
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"strings"
+
+	yaml "gopkg.in/yaml.v2"
+)
+
+// BasicAuth contains basic HTTP authentication credentials.
+type BasicAuth struct {
+	Username string `yaml:"username"`
+	Password Secret `yaml:"password"`
+
+	// Catches all undefined fields and must be empty after parsing.
+	XXX map[string]interface{} `yaml:",inline"`
+}
+
+// URL is a custom URL type that allows validation at configuration load time.
+type URL struct {
+	*url.URL
+}
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface for URLs.
+func (u *URL) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var s string
+	if err := unmarshal(&s); err != nil {
+		return err
+	}
+
+	urlp, err := url.Parse(s)
+	if err != nil {
+		return err
+	}
+	u.URL = urlp
+	return nil
+}
+
+// MarshalYAML implements the yaml.Marshaler interface for URLs.
+func (u URL) MarshalYAML() (interface{}, error) {
+	if u.URL != nil {
+		return u.String(), nil
+	}
+	return nil, nil
+}
+
+// HTTPClientConfig configures an HTTP client.
+type HTTPClientConfig struct {
+	// The HTTP basic authentication credentials for the targets.
+	BasicAuth *BasicAuth `yaml:"basic_auth,omitempty"`
+	// The bearer token for the targets.
+	BearerToken Secret `yaml:"bearer_token,omitempty"`
+	// The bearer token file for the targets.
+	BearerTokenFile string `yaml:"bearer_token_file,omitempty"`
+	// HTTP proxy server to use to connect to the targets.
+	ProxyURL URL `yaml:"proxy_url,omitempty"`
+	// TLSConfig to use to connect to the targets.
+	TLSConfig TLSConfig `yaml:"tls_config,omitempty"`
+
+	// Catches all undefined fields and must be empty after parsing.
+	XXX map[string]interface{} `yaml:",inline"`
+}
+
+func (c *HTTPClientConfig) validate() error {
+	if len(c.BearerToken) > 0 && len(c.BearerTokenFile) > 0 {
+		return fmt.Errorf("at most one of bearer_token & bearer_token_file must be configured")
+	}
+	if c.BasicAuth != nil && (len(c.BearerToken) > 0 || len(c.BearerTokenFile) > 0) {
+		return fmt.Errorf("at most one of basic_auth, bearer_token & bearer_token_file must be configured")
+	}
+	return nil
+}
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface
+func (c *HTTPClientConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	type plain HTTPClientConfig
+	err := unmarshal((*plain)(c))
+	if err != nil {
+		return err
+	}
+	err = c.validate()
+	if err != nil {
+		return c.validate()
+	}
+	return checkOverflow(c.XXX, "http_client_config")
+}
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface.
+func (a *BasicAuth) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	type plain BasicAuth
+	err := unmarshal((*plain)(a))
+	if err != nil {
+		return err
+	}
+	return checkOverflow(a.XXX, "basic_auth")
+}
+
+// NewHTTPClientFromConfig returns a new HTTP client configured for the
+// given config.HTTPClientConfig.
+func NewHTTPClientFromConfig(cfg *HTTPClientConfig) (*http.Client, error) {
+	tlsConfig, err := NewTLSConfig(&cfg.TLSConfig)
+	if err != nil {
+		return nil, err
+	}
+
+	// It's the caller's job to handle timeouts
+	var rt http.RoundTripper = &http.Transport{
+		Proxy:             http.ProxyURL(cfg.ProxyURL.URL),
+		DisableKeepAlives: true,
+		TLSClientConfig:   tlsConfig,
+	}
+
+	// If a bearer token is provided, create a round tripper that will set the
+	// Authorization header correctly on each request.
+	bearerToken := cfg.BearerToken
+	if len(bearerToken) == 0 && len(cfg.BearerTokenFile) > 0 {
+		b, err := ioutil.ReadFile(cfg.BearerTokenFile)
+		if err != nil {
+			return nil, fmt.Errorf("unable to read bearer token file %s: %s", cfg.BearerTokenFile, err)
+		}
+		bearerToken = Secret(strings.TrimSpace(string(b)))
+	}
+
+	if len(bearerToken) > 0 {
+		rt = NewBearerAuthRoundTripper(bearerToken, rt)
+	}
+
+	if cfg.BasicAuth != nil {
+		rt = NewBasicAuthRoundTripper(cfg.BasicAuth.Username, Secret(cfg.BasicAuth.Password), rt)
+	}
+
+	// Return a new client with the configured round tripper.
+	return &http.Client{Transport: rt}, nil
+}
+
+type bearerAuthRoundTripper struct {
+	bearerToken Secret
+	rt          http.RoundTripper
+}
+
+type basicAuthRoundTripper struct {
+	username string
+	password Secret
+	rt       http.RoundTripper
+}
+
+// NewBasicAuthRoundTripper will apply a BASIC auth authorization header to a request unless it has
+// already been set.
+func NewBasicAuthRoundTripper(username string, password Secret, rt http.RoundTripper) http.RoundTripper {
+	return &basicAuthRoundTripper{username, password, rt}
+}
+
+func (rt *bearerAuthRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	if len(req.Header.Get("Authorization")) == 0 {
+		req = cloneRequest(req)
+		req.Header.Set("Authorization", "Bearer "+string(rt.bearerToken))
+	}
+
+	return rt.rt.RoundTrip(req)
+}
+
+// NewBearerAuthRoundTripper adds the provided bearer token to a request unless the authorization
+// header has already been set.
+func NewBearerAuthRoundTripper(bearer Secret, rt http.RoundTripper) http.RoundTripper {
+	return &bearerAuthRoundTripper{bearer, rt}
+}
+
+func (rt *basicAuthRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	if len(req.Header.Get("Authorization")) != 0 {
+		return rt.RoundTrip(req)
+	}
+	req = cloneRequest(req)
+	req.SetBasicAuth(rt.username, string(rt.password))
+	return rt.rt.RoundTrip(req)
+}
+
+// cloneRequest returns a clone of the provided *http.Request.
+// The clone is a shallow copy of the struct and its Header map.
+func cloneRequest(r *http.Request) *http.Request {
+	// Shallow copy of the struct.
+	r2 := new(http.Request)
+	*r2 = *r
+	// Deep copy of the Header.
+	r2.Header = make(http.Header)
+	for k, s := range r.Header {
+		r2.Header[k] = s
+	}
+	return r2
+}
+
+// NewTLSConfig creates a new tls.Config from the given config.TLSConfig.
+func NewTLSConfig(cfg *TLSConfig) (*tls.Config, error) {
+	tlsConfig := &tls.Config{InsecureSkipVerify: cfg.InsecureSkipVerify}
+
+	// If a CA cert is provided then let's read it in so we can validate the
+	// scrape target's certificate properly.
+	if len(cfg.CAFile) > 0 {
+		caCertPool := x509.NewCertPool()
+		// Load CA cert.
+		caCert, err := ioutil.ReadFile(cfg.CAFile)
+		if err != nil {
+			return nil, fmt.Errorf("unable to use specified CA cert %s: %s", cfg.CAFile, err)
+		}
+		caCertPool.AppendCertsFromPEM(caCert)
+		tlsConfig.RootCAs = caCertPool
+	}
+
+	if len(cfg.ServerName) > 0 {
+		tlsConfig.ServerName = cfg.ServerName
+	}
+
+	// If a client cert & key is provided then configure TLS config accordingly.
+	if len(cfg.CertFile) > 0 && len(cfg.KeyFile) == 0 {
+		return nil, fmt.Errorf("client cert file %q specified without client key file", cfg.CertFile)
+	} else if len(cfg.KeyFile) > 0 && len(cfg.CertFile) == 0 {
+		return nil, fmt.Errorf("client key file %q specified without client cert file", cfg.KeyFile)
+	} else if len(cfg.CertFile) > 0 && len(cfg.KeyFile) > 0 {
+		cert, err := tls.LoadX509KeyPair(cfg.CertFile, cfg.KeyFile)
+		if err != nil {
+			return nil, fmt.Errorf("unable to use specified client cert (%s) & key (%s): %s", cfg.CertFile, cfg.KeyFile, err)
+		}
+		tlsConfig.Certificates = []tls.Certificate{cert}
+	}
+	tlsConfig.BuildNameToCertificate()
+
+	return tlsConfig, nil
+}
+
+// TLSConfig configures the options for TLS connections.
+type TLSConfig struct {
+	// The CA cert to use for the targets.
+	CAFile string `yaml:"ca_file,omitempty"`
+	// The client cert file for the targets.
+	CertFile string `yaml:"cert_file,omitempty"`
+	// The client key file for the targets.
+	KeyFile string `yaml:"key_file,omitempty"`
+	// Used to verify the hostname for the targets.
+	ServerName string `yaml:"server_name,omitempty"`
+	// Disable target certificate validation.
+	InsecureSkipVerify bool `yaml:"insecure_skip_verify"`
+
+	// Catches all undefined fields and must be empty after parsing.
+	XXX map[string]interface{} `yaml:",inline"`
+}
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface.
+func (c *TLSConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	type plain TLSConfig
+	if err := unmarshal((*plain)(c)); err != nil {
+		return err
+	}
+	return checkOverflow(c.XXX, "TLS config")
+}
+
+func (c HTTPClientConfig) String() string {
+	b, err := yaml.Marshal(c)
+	if err != nil {
+		return fmt.Sprintf("<error creating http client config string: %s>", err)
+	}
+	return string(b)
+}

vendor/github.com/prometheus/common/config/http_config_test.go

@@ -0,0 +1,157 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package config
+
+import (
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"strings"
+	"testing"
+
+	yaml "gopkg.in/yaml.v2"
+)
+
+var invalidHTTPClientConfigs = []struct {
+	httpClientConfigFile string
+	errMsg               string
+}{
+	{
+		httpClientConfigFile: "testdata/http.conf.bearer-token-and-file-set.bad.yml",
+		errMsg:               "at most one of bearer_token & bearer_token_file must be configured",
+	},
+	{
+		httpClientConfigFile: "testdata/http.conf.empty.bad.yml",
+		errMsg:               "at most one of basic_auth, bearer_token & bearer_token_file must be configured",
+	},
+}
+
+func TestAuthRoundTrippers(t *testing.T) {
+
+	cfg, _, err := LoadHTTPConfigFile("testdata/http.conf.good.yml")
+	if err != nil {
+		t.Errorf("Error loading HTTP client config: %v", err)
+	}
+
+	tlsConfig, err := NewTLSConfig(&cfg.TLSConfig)
+	if err != nil {
+		t.Errorf("Error creating new TLS config: %v", err)
+	}
+
+	rt := &http.Transport{
+		Proxy:             http.ProxyURL(cfg.ProxyURL.URL),
+		DisableKeepAlives: true,
+		TLSClientConfig:   tlsConfig,
+	}
+	req := new(http.Request)
+
+	bearerAuthRoundTripper := NewBearerAuthRoundTripper("mysecret", rt)
+	bearerAuthRoundTripper.RoundTrip(req)
+
+	basicAuthRoundTripper := NewBasicAuthRoundTripper("username", "password", rt)
+	basicAuthRoundTripper.RoundTrip(req)
+}
+
+func TestHideHTTPClientConfigSecrets(t *testing.T) {
+	c, _, err := LoadHTTPConfigFile("testdata/http.conf.good.yml")
+	if err != nil {
+		t.Errorf("Error parsing %s: %s", "testdata/http.conf.good.yml", err)
+	}
+
+	// String method must not reveal authentication credentials.
+	s := c.String()
+	if strings.Contains(s, "mysecret") {
+		t.Fatal("http client config's String method reveals authentication credentials.")
+	}
+}
+
+func mustParseURL(u string) *URL {
+	parsed, err := url.Parse(u)
+	if err != nil {
+		panic(err)
+	}
+	return &URL{URL: parsed}
+}
+
+func TestNewClientFromConfig(t *testing.T) {
+	cfg, _, err := LoadHTTPConfigFile("testdata/http.conf.good.yml")
+	if err != nil {
+		t.Errorf("Error loading HTTP client config: %v", err)
+	}
+	_, err = NewHTTPClientFromConfig(cfg)
+	if err != nil {
+		t.Errorf("Error creating new client from config: %v", err)
+	}
+}
+
+func TestNewClientFromInvalidConfig(t *testing.T) {
+	cfg, _, err := LoadHTTPConfigFile("testdata/http.conf.invalid-bearer-token-file.bad.yml")
+	if err != nil {
+		t.Errorf("Error loading HTTP client config: %v", err)
+	}
+	_, err = NewHTTPClientFromConfig(cfg)
+	if err == nil {
+		t.Error("Expected error creating new client from invalid config but got none")
+	}
+	if !strings.Contains(err.Error(), "unable to read bearer token file file: open file: no such file or directory") {
+		t.Errorf("Expected error with config but got: %s", err.Error())
+	}
+}
+
+func TestValidateHTTPConfig(t *testing.T) {
+	cfg, _, err := LoadHTTPConfigFile("testdata/http.conf.good.yml")
+	if err != nil {
+		t.Errorf("Error loading HTTP client config: %v", err)
+	}
+	err = cfg.validate()
+	if err != nil {
+		t.Fatalf("Error validating %s: %s", "testdata/http.conf.good.yml", err)
+	}
+}
+
+func TestInvalidHTTPConfigs(t *testing.T) {
+	for _, ee := range invalidHTTPClientConfigs {
+		_, _, err := LoadHTTPConfigFile(ee.httpClientConfigFile)
+		if err == nil {
+			t.Error("Expected error with config but got none")
+			continue
+		}
+		if !strings.Contains(err.Error(), ee.errMsg) {
+			t.Errorf("Expected error for invalid HTTP client configuration to contain %q but got: %s", ee.errMsg, err)
+		}
+	}
+}
+
+// LoadHTTPConfig parses the YAML input s into a HTTPClientConfig.
+func LoadHTTPConfig(s string) (*HTTPClientConfig, error) {
+	cfg := &HTTPClientConfig{}
+	err := yaml.Unmarshal([]byte(s), cfg)
+	if err != nil {
+		return nil, err
+	}
+	return cfg, nil
+}
+
+// LoadHTTPConfigFile parses the given YAML file into a HTTPClientConfig.
+func LoadHTTPConfigFile(filename string) (*HTTPClientConfig, []byte, error) {
+	content, err := ioutil.ReadFile(filename)
+	if err != nil {
+		return nil, nil, err
+	}
+	cfg, err := LoadHTTPConfig(string(content))
+	if err != nil {
+		return nil, nil, err
+	}
+	return cfg, content, nil
+}

vendor/github.com/prometheus/common/config/testdata/http.conf.bearer-token-and-file-set.bad.yml

@@ -0,0 +1,5 @@
+basic_auth:
+  username: username
+  password: "mysecret"
+bearer_token: mysecret
+bearer_token_file: file

vendor/github.com/prometheus/common/config/testdata/http.conf.empty.bad.yml

@@ -0,0 +1,4 @@
+basic_auth:
+  username: username
+  password: mysecret
+bearer_token_file: file

vendor/github.com/prometheus/common/config/testdata/http.conf.good.yml

@@ -0,0 +1,4 @@
+basic_auth:
+  username: username
+  password: "mysecret"
+proxy_url: "http://remote.host"

vendor/github.com/prometheus/common/config/testdata/http.conf.invalid-bearer-token-file.bad.yml

@@ -0,0 +1 @@
+bearer_token_file: file

vendor/github.com/prometheus/common/config/testdata/tls_config.cert_no_key.bad.yml

@@ -0,0 +1 @@
+cert_file: somefile

vendor/github.com/prometheus/common/config/testdata/tls_config.insecure.good.yml

@@ -0,0 +1 @@
+insecure_skip_verify: true

vendor/github.com/prometheus/common/config/testdata/tls_config.invalid_field.bad.yml

@@ -0,0 +1 @@
+something_invalid: true

vendor/github.com/prometheus/common/config/testdata/tls_config.key_no_cert.bad.yml

@@ -0,0 +1 @@
+key_file: somefile

vendor/github.com/prometheus/common/config/tls_config_test.go

@@ -0,0 +1,92 @@
+// Copyright 2016 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package config
+
+import (
+	"crypto/tls"
+	"io/ioutil"
+	"reflect"
+	"strings"
+	"testing"
+
+	"gopkg.in/yaml.v2"
+)
+
+// LoadTLSConfig parses the given YAML file into a tls.Config.
+func LoadTLSConfig(filename string) (*tls.Config, error) {
+	content, err := ioutil.ReadFile(filename)
+	if err != nil {
+		return nil, err
+	}
+	cfg := &TLSConfig{}
+	if err = yaml.Unmarshal(content, cfg); err != nil {
+		return nil, err
+	}
+	return NewTLSConfig(cfg)
+}
+
+var expectedTLSConfigs = []struct {
+	filename string
+	config   *tls.Config
+}{
+	{
+		filename: "tls_config.empty.good.yml",
+		config:   &tls.Config{},
+	}, {
+		filename: "tls_config.insecure.good.yml",
+		config:   &tls.Config{InsecureSkipVerify: true},
+	},
+}
+
+func TestValidTLSConfig(t *testing.T) {
+	for _, cfg := range expectedTLSConfigs {
+		cfg.config.BuildNameToCertificate()
+		got, err := LoadTLSConfig("testdata/" + cfg.filename)
+		if err != nil {
+			t.Errorf("Error parsing %s: %s", cfg.filename, err)
+		}
+		if !reflect.DeepEqual(*got, *cfg.config) {
+			t.Fatalf("%v: unexpected config result: \n\n%v\n expected\n\n%v", cfg.filename, got, cfg.config)
+		}
+	}
+}
+
+var expectedTLSConfigErrors = []struct {
+	filename string
+	errMsg   string
+}{
+	{
+		filename: "tls_config.invalid_field.bad.yml",
+		errMsg:   "unknown fields in",
+	}, {
+		filename: "tls_config.cert_no_key.bad.yml",
+		errMsg:   "specified without client key file",
+	}, {
+		filename: "tls_config.key_no_cert.bad.yml",
+		errMsg:   "specified without client cert file",
+	},
+}
+
+func TestBadTLSConfigs(t *testing.T) {
+	for _, ee := range expectedTLSConfigErrors {
+		_, err := LoadTLSConfig("testdata/" + ee.filename)
+		if err == nil {
+			t.Errorf("Expected error parsing %s but got none", ee.filename)
+			continue
+		}
+		if !strings.Contains(err.Error(), ee.errMsg) {
+			t.Errorf("Expected error for %s to contain %q but got: %s", ee.filename, ee.errMsg, err)
+		}
+	}
+}

vendor/github.com/prometheus/common/expfmt/bench_test.go

@@ -0,0 +1,167 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"bytes"
+	"compress/gzip"
+	"io"
+	"io/ioutil"
+	"testing"
+
+	"github.com/matttproud/golang_protobuf_extensions/pbutil"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+var parser TextParser
+
+// Benchmarks to show how much penalty text format parsing actually inflicts.
+//
+// Example results on Linux 3.13.0, Intel(R) Core(TM) i7-4700MQ CPU @ 2.40GHz, go1.4.
+//
+// BenchmarkParseText          1000           1188535 ns/op          205085 B/op       6135 allocs/op
+// BenchmarkParseTextGzip      1000           1376567 ns/op          246224 B/op       6151 allocs/op
+// BenchmarkParseProto        10000            172790 ns/op           52258 B/op       1160 allocs/op
+// BenchmarkParseProtoGzip     5000            324021 ns/op           94931 B/op       1211 allocs/op
+// BenchmarkParseProtoMap     10000            187946 ns/op           58714 B/op       1203 allocs/op
+//
+// CONCLUSION: The overhead for the map is negligible. Text format needs ~5x more allocations.
+// Without compression, it needs ~7x longer, but with compression (the more relevant scenario),
+// the difference becomes less relevant, only ~4x.
+//
+// The test data contains 248 samples.
+
+// BenchmarkParseText benchmarks the parsing of a text-format scrape into metric
+// family DTOs.
+func BenchmarkParseText(b *testing.B) {
+	b.StopTimer()
+	data, err := ioutil.ReadFile("testdata/text")
+	if err != nil {
+		b.Fatal(err)
+	}
+	b.StartTimer()
+
+	for i := 0; i < b.N; i++ {
+		if _, err := parser.TextToMetricFamilies(bytes.NewReader(data)); err != nil {
+			b.Fatal(err)
+		}
+	}
+}
+
+// BenchmarkParseTextGzip benchmarks the parsing of a gzipped text-format scrape
+// into metric family DTOs.
+func BenchmarkParseTextGzip(b *testing.B) {
+	b.StopTimer()
+	data, err := ioutil.ReadFile("testdata/text.gz")
+	if err != nil {
+		b.Fatal(err)
+	}
+	b.StartTimer()
+
+	for i := 0; i < b.N; i++ {
+		in, err := gzip.NewReader(bytes.NewReader(data))
+		if err != nil {
+			b.Fatal(err)
+		}
+		if _, err := parser.TextToMetricFamilies(in); err != nil {
+			b.Fatal(err)
+		}
+	}
+}
+
+// BenchmarkParseProto benchmarks the parsing of a protobuf-format scrape into
+// metric family DTOs. Note that this does not build a map of metric families
+// (as the text version does), because it is not required for Prometheus
+// ingestion either. (However, it is required for the text-format parsing, as
+// the metric family might be sprinkled all over the text, while the
+// protobuf-format guarantees bundling at one place.)
+func BenchmarkParseProto(b *testing.B) {
+	b.StopTimer()
+	data, err := ioutil.ReadFile("testdata/protobuf")
+	if err != nil {
+		b.Fatal(err)
+	}
+	b.StartTimer()
+
+	for i := 0; i < b.N; i++ {
+		family := &dto.MetricFamily{}
+		in := bytes.NewReader(data)
+		for {
+			family.Reset()
+			if _, err := pbutil.ReadDelimited(in, family); err != nil {
+				if err == io.EOF {
+					break
+				}
+				b.Fatal(err)
+			}
+		}
+	}
+}
+
+// BenchmarkParseProtoGzip is like BenchmarkParseProto above, but parses gzipped
+// protobuf format.
+func BenchmarkParseProtoGzip(b *testing.B) {
+	b.StopTimer()
+	data, err := ioutil.ReadFile("testdata/protobuf.gz")
+	if err != nil {
+		b.Fatal(err)
+	}
+	b.StartTimer()
+
+	for i := 0; i < b.N; i++ {
+		family := &dto.MetricFamily{}
+		in, err := gzip.NewReader(bytes.NewReader(data))
+		if err != nil {
+			b.Fatal(err)
+		}
+		for {
+			family.Reset()
+			if _, err := pbutil.ReadDelimited(in, family); err != nil {
+				if err == io.EOF {
+					break
+				}
+				b.Fatal(err)
+			}
+		}
+	}
+}
+
+// BenchmarkParseProtoMap is like BenchmarkParseProto but DOES put the parsed
+// metric family DTOs into a map. This is not happening during Prometheus
+// ingestion. It is just here to measure the overhead of that map creation and
+// separate it from the overhead of the text format parsing.
+func BenchmarkParseProtoMap(b *testing.B) {
+	b.StopTimer()
+	data, err := ioutil.ReadFile("testdata/protobuf")
+	if err != nil {
+		b.Fatal(err)
+	}
+	b.StartTimer()
+
+	for i := 0; i < b.N; i++ {
+		families := map[string]*dto.MetricFamily{}
+		in := bytes.NewReader(data)
+		for {
+			family := &dto.MetricFamily{}
+			if _, err := pbutil.ReadDelimited(in, family); err != nil {
+				if err == io.EOF {
+					break
+				}
+				b.Fatal(err)
+			}
+			families[family.GetName()] = family
+		}
+	}
+}

vendor/github.com/prometheus/common/expfmt/decode_test.go

@@ -0,0 +1,435 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"io"
+	"net/http"
+	"reflect"
+	"sort"
+	"strings"
+	"testing"
+
+	"github.com/golang/protobuf/proto"
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/prometheus/common/model"
+)
+
+func TestTextDecoder(t *testing.T) {
+	var (
+		ts = model.Now()
+		in = `
+# Only a quite simple scenario with two metric families.
+# More complicated tests of the parser itself can be found in the text package.
+# TYPE mf2 counter
+mf2 3
+mf1{label="value1"} -3.14 123456
+mf1{label="value2"} 42
+mf2 4
+`
+		out = model.Vector{
+			&model.Sample{
+				Metric: model.Metric{
+					model.MetricNameLabel: "mf1",
+					"label":               "value1",
+				},
+				Value:     -3.14,
+				Timestamp: 123456,
+			},
+			&model.Sample{
+				Metric: model.Metric{
+					model.MetricNameLabel: "mf1",
+					"label":               "value2",
+				},
+				Value:     42,
+				Timestamp: ts,
+			},
+			&model.Sample{
+				Metric: model.Metric{
+					model.MetricNameLabel: "mf2",
+				},
+				Value:     3,
+				Timestamp: ts,
+			},
+			&model.Sample{
+				Metric: model.Metric{
+					model.MetricNameLabel: "mf2",
+				},
+				Value:     4,
+				Timestamp: ts,
+			},
+		}
+	)
+
+	dec := &SampleDecoder{
+		Dec: &textDecoder{r: strings.NewReader(in)},
+		Opts: &DecodeOptions{
+			Timestamp: ts,
+		},
+	}
+	var all model.Vector
+	for {
+		var smpls model.Vector
+		err := dec.Decode(&smpls)
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			t.Fatal(err)
+		}
+		all = append(all, smpls...)
+	}
+	sort.Sort(all)
+	sort.Sort(out)
+	if !reflect.DeepEqual(all, out) {
+		t.Fatalf("output does not match")
+	}
+}
+
+func TestProtoDecoder(t *testing.T) {
+
+	var testTime = model.Now()
+
+	scenarios := []struct {
+		in       string
+		expected model.Vector
+		fail     bool
+	}{
+		{
+			in: "",
+		},
+		{
+			in:   "\x8f\x01\n\rrequest_count\x12\x12Number of requests\x18\x00\"0\n#\n\x0fsome_!abel_name\x12\x10some_label_value\x1a\t\t\x00\x00\x00\x00\x00\x00E\xc0\"6\n)\n\x12another_label_name\x12\x13another_label_value\x1a\t\t\x00\x00\x00\x00\x00\x00U@",
+			fail: true,
+		},
+		{
+			in: "\x8f\x01\n\rrequest_count\x12\x12Number of requests\x18\x00\"0\n#\n\x0fsome_label_name\x12\x10some_label_value\x1a\t\t\x00\x00\x00\x00\x00\x00E\xc0\"6\n)\n\x12another_label_name\x12\x13another_label_value\x1a\t\t\x00\x00\x00\x00\x00\x00U@",
+			expected: model.Vector{
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_count",
+						"some_label_name":     "some_label_value",
+					},
+					Value:     -42,
+					Timestamp: testTime,
+				},
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_count",
+						"another_label_name":  "another_label_value",
+					},
+					Value:     84,
+					Timestamp: testTime,
+				},
+			},
+		},
+		{
+			in: "\xb9\x01\n\rrequest_count\x12\x12Number of requests\x18\x02\"O\n#\n\x0fsome_label_name\x12\x10some_label_value\"(\x1a\x12\t\xaeG\xe1z\x14\xae\xef?\x11\x00\x00\x00\x00\x00\x00E\xc0\x1a\x12\t+\x87\x16\xd9\xce\xf7\xef?\x11\x00\x00\x00\x00\x00\x00U\xc0\"A\n)\n\x12another_label_name\x12\x13another_label_value\"\x14\x1a\x12\t\x00\x00\x00\x00\x00\x00\xe0?\x11\x00\x00\x00\x00\x00\x00$@",
+			expected: model.Vector{
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_count_count",
+						"some_label_name":     "some_label_value",
+					},
+					Value:     0,
+					Timestamp: testTime,
+				},
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_count_sum",
+						"some_label_name":     "some_label_value",
+					},
+					Value:     0,
+					Timestamp: testTime,
+				},
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_count",
+						"some_label_name":     "some_label_value",
+						"quantile":            "0.99",
+					},
+					Value:     -42,
+					Timestamp: testTime,
+				},
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_count",
+						"some_label_name":     "some_label_value",
+						"quantile":            "0.999",
+					},
+					Value:     -84,
+					Timestamp: testTime,
+				},
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_count_count",
+						"another_label_name":  "another_label_value",
+					},
+					Value:     0,
+					Timestamp: testTime,
+				},
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_count_sum",
+						"another_label_name":  "another_label_value",
+					},
+					Value:     0,
+					Timestamp: testTime,
+				},
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_count",
+						"another_label_name":  "another_label_value",
+						"quantile":            "0.5",
+					},
+					Value:     10,
+					Timestamp: testTime,
+				},
+			},
+		},
+		{
+			in: "\x8d\x01\n\x1drequest_duration_microseconds\x12\x15The response latency.\x18\x04\"S:Q\b\x85\x15\x11\xcd\xcc\xccL\x8f\xcb:A\x1a\v\b{\x11\x00\x00\x00\x00\x00\x00Y@\x1a\f\b\x9c\x03\x11\x00\x00\x00\x00\x00\x00^@\x1a\f\b\xd0\x04\x11\x00\x00\x00\x00\x00\x00b@\x1a\f\b\xf4\v\x11\x9a\x99\x99\x99\x99\x99e@\x1a\f\b\x85\x15\x11\x00\x00\x00\x00\x00\x00\xf0\u007f",
+			expected: model.Vector{
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_duration_microseconds_bucket",
+						"le": "100",
+					},
+					Value:     123,
+					Timestamp: testTime,
+				},
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_duration_microseconds_bucket",
+						"le": "120",
+					},
+					Value:     412,
+					Timestamp: testTime,
+				},
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_duration_microseconds_bucket",
+						"le": "144",
+					},
+					Value:     592,
+					Timestamp: testTime,
+				},
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_duration_microseconds_bucket",
+						"le": "172.8",
+					},
+					Value:     1524,
+					Timestamp: testTime,
+				},
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_duration_microseconds_bucket",
+						"le": "+Inf",
+					},
+					Value:     2693,
+					Timestamp: testTime,
+				},
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_duration_microseconds_sum",
+					},
+					Value:     1756047.3,
+					Timestamp: testTime,
+				},
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_duration_microseconds_count",
+					},
+					Value:     2693,
+					Timestamp: testTime,
+				},
+			},
+		},
+		{
+			// The metric type is unset in this protobuf, which needs to be handled
+			// correctly by the decoder.
+			in: "\x1c\n\rrequest_count\"\v\x1a\t\t\x00\x00\x00\x00\x00\x00\xf0?",
+			expected: model.Vector{
+				&model.Sample{
+					Metric: model.Metric{
+						model.MetricNameLabel: "request_count",
+					},
+					Value:     1,
+					Timestamp: testTime,
+				},
+			},
+		},
+	}
+
+	for i, scenario := range scenarios {
+		dec := &SampleDecoder{
+			Dec: &protoDecoder{r: strings.NewReader(scenario.in)},
+			Opts: &DecodeOptions{
+				Timestamp: testTime,
+			},
+		}
+
+		var all model.Vector
+		for {
+			var smpls model.Vector
+			err := dec.Decode(&smpls)
+			if err == io.EOF {
+				break
+			}
+			if scenario.fail {
+				if err == nil {
+					t.Fatal("Expected error but got none")
+				}
+				break
+			}
+			if err != nil {
+				t.Fatal(err)
+			}
+			all = append(all, smpls...)
+		}
+		sort.Sort(all)
+		sort.Sort(scenario.expected)
+		if !reflect.DeepEqual(all, scenario.expected) {
+			t.Fatalf("%d. output does not match, want: %#v, got %#v", i, scenario.expected, all)
+		}
+	}
+}
+
+func testDiscriminatorHTTPHeader(t testing.TB) {
+	var scenarios = []struct {
+		input  map[string]string
+		output Format
+		err    error
+	}{
+		{
+			input:  map[string]string{"Content-Type": `application/vnd.google.protobuf; proto="io.prometheus.client.MetricFamily"; encoding="delimited"`},
+			output: FmtProtoDelim,
+		},
+		{
+			input:  map[string]string{"Content-Type": `application/vnd.google.protobuf; proto="illegal"; encoding="delimited"`},
+			output: FmtUnknown,
+		},
+		{
+			input:  map[string]string{"Content-Type": `application/vnd.google.protobuf; proto="io.prometheus.client.MetricFamily"; encoding="illegal"`},
+			output: FmtUnknown,
+		},
+		{
+			input:  map[string]string{"Content-Type": `text/plain; version=0.0.4`},
+			output: FmtText,
+		},
+		{
+			input:  map[string]string{"Content-Type": `text/plain`},
+			output: FmtText,
+		},
+		{
+			input:  map[string]string{"Content-Type": `text/plain; version=0.0.3`},
+			output: FmtUnknown,
+		},
+	}
+
+	for i, scenario := range scenarios {
+		var header http.Header
+
+		if len(scenario.input) > 0 {
+			header = http.Header{}
+		}
+
+		for key, value := range scenario.input {
+			header.Add(key, value)
+		}
+
+		actual := ResponseFormat(header)
+
+		if scenario.output != actual {
+			t.Errorf("%d. expected %s, got %s", i, scenario.output, actual)
+		}
+	}
+}
+
+func TestDiscriminatorHTTPHeader(t *testing.T) {
+	testDiscriminatorHTTPHeader(t)
+}
+
+func BenchmarkDiscriminatorHTTPHeader(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		testDiscriminatorHTTPHeader(b)
+	}
+}
+
+func TestExtractSamples(t *testing.T) {
+	var (
+		goodMetricFamily1 = &dto.MetricFamily{
+			Name: proto.String("foo"),
+			Help: proto.String("Help for foo."),
+			Type: dto.MetricType_COUNTER.Enum(),
+			Metric: []*dto.Metric{
+				&dto.Metric{
+					Counter: &dto.Counter{
+						Value: proto.Float64(4711),
+					},
+				},
+			},
+		}
+		goodMetricFamily2 = &dto.MetricFamily{
+			Name: proto.String("bar"),
+			Help: proto.String("Help for bar."),
+			Type: dto.MetricType_GAUGE.Enum(),
+			Metric: []*dto.Metric{
+				&dto.Metric{
+					Gauge: &dto.Gauge{
+						Value: proto.Float64(3.14),
+					},
+				},
+			},
+		}
+		badMetricFamily = &dto.MetricFamily{
+			Name: proto.String("bad"),
+			Help: proto.String("Help for bad."),
+			Type: dto.MetricType(42).Enum(),
+			Metric: []*dto.Metric{
+				&dto.Metric{
+					Gauge: &dto.Gauge{
+						Value: proto.Float64(2.7),
+					},
+				},
+			},
+		}
+
+		opts = &DecodeOptions{
+			Timestamp: 42,
+		}
+	)
+
+	got, err := ExtractSamples(opts, goodMetricFamily1, goodMetricFamily2)
+	if err != nil {
+		t.Error("Unexpected error from ExtractSamples:", err)
+	}
+	want := model.Vector{
+		&model.Sample{Metric: model.Metric{model.MetricNameLabel: "foo"}, Value: 4711, Timestamp: 42},
+		&model.Sample{Metric: model.Metric{model.MetricNameLabel: "bar"}, Value: 3.14, Timestamp: 42},
+	}
+	if !reflect.DeepEqual(got, want) {
+		t.Errorf("unexpected samples extracted, got: %v, want: %v", got, want)
+	}
+
+	got, err = ExtractSamples(opts, goodMetricFamily1, badMetricFamily, goodMetricFamily2)
+	if err == nil {
+		t.Error("Expected error from ExtractSamples")
+	}
+	if !reflect.DeepEqual(got, want) {
+		t.Errorf("unexpected samples extracted, got: %v, want: %v", got, want)
+	}
+}

vendor/github.com/prometheus/common/expfmt/fuzz/corpus/from_test_parse_0

@@ -0,0 +1,2 @@
+
+

vendor/github.com/prometheus/common/expfmt/fuzz/corpus/from_test_parse_1

@@ -0,0 +1,6 @@
+
+minimal_metric 1.234
+another_metric -3e3 103948
+# Even that:
+no_labels{} 3
+# HELP line for non-existing metric will be ignored.

vendor/github.com/prometheus/common/expfmt/fuzz/corpus/from_test_parse_2

@@ -0,0 +1,12 @@
+
+# A normal comment.
+#
+# TYPE name counter
+name{labelname="val1",basename="basevalue"} NaN
+name {labelname="val2",basename="base\"v\\al\nue"} 0.23 1234567890
+# HELP name two-line\n doc  str\\ing
+
+ # HELP  name2  	doc str"ing 2
+  #    TYPE    name2 gauge
+name2{labelname="val2"	,basename   =   "basevalue2"		} +Inf 54321
+name2{ labelname = "val1" , }-Inf

vendor/github.com/prometheus/common/expfmt/fuzz/corpus/from_test_parse_3

@@ -0,0 +1,22 @@
+
+# TYPE my_summary summary
+my_summary{n1="val1",quantile="0.5"} 110
+decoy -1 -2
+my_summary{n1="val1",quantile="0.9"} 140 1
+my_summary_count{n1="val1"} 42
+# Latest timestamp wins in case of a summary.
+my_summary_sum{n1="val1"} 4711 2
+fake_sum{n1="val1"} 2001
+# TYPE another_summary summary
+another_summary_count{n2="val2",n1="val1"} 20
+my_summary_count{n2="val2",n1="val1"} 5 5
+another_summary{n1="val1",n2="val2",quantile=".3"} -1.2
+my_summary_sum{n1="val2"} 08 15
+my_summary{n1="val3", quantile="0.2"} 4711
+  my_summary{n1="val1",n2="val2",quantile="-12.34",} NaN
+# some
+# funny comments
+# HELP 
+# HELP
+# HELP my_summary
+# HELP my_summary 

vendor/github.com/prometheus/common/expfmt/fuzz/corpus/from_test_parse_4

@@ -0,0 +1,10 @@
+
+# HELP request_duration_microseconds The response latency.
+# TYPE request_duration_microseconds histogram
+request_duration_microseconds_bucket{le="100"} 123
+request_duration_microseconds_bucket{le="120"} 412
+request_duration_microseconds_bucket{le="144"} 592
+request_duration_microseconds_bucket{le="172.8"} 1524
+request_duration_microseconds_bucket{le="+Inf"} 2693
+request_duration_microseconds_sum 1.7560473e+06
+request_duration_microseconds_count 2693

vendor/github.com/prometheus/common/expfmt/fuzz/corpus/from_test_parse_error_0

@@ -0,0 +1 @@
+bla 3.14

vendor/github.com/prometheus/common/expfmt/fuzz/corpus/from_test_parse_error_1

@@ -0,0 +1 @@
+metric{label="\t"} 3.14

vendor/github.com/prometheus/common/expfmt/fuzz/corpus/from_test_parse_error_10

@@ -0,0 +1 @@
+metric{label="bla"} 3.14 2 3