Cleanup collection of prometheus metrics

controllers/nginx/pkg/metric/collector/process.go

@@ -0,0 +1,157 @@
+/*
+Copyright 2017 The Kubernetes 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 collector
+
+import (
+	"path/filepath"
+
+	"github.com/golang/glog"
+	common "github.com/ncabatoff/process-exporter"
+	"github.com/ncabatoff/process-exporter/proc"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+type BinaryNameMatcher struct {
+	name string
+	args []string
+}
+
+func (em BinaryNameMatcher) MatchAndName(nacl common.NameAndCmdline) (bool, string) {
+	if len(nacl.Cmdline) == 0 {
+		return false, ""
+	}
+	cmd := filepath.Base(nacl.Cmdline[0])
+	return em.name == cmd, ""
+}
+
+var (
+	numprocsDesc = prometheus.NewDesc(
+		"nginx_num_procs",
+		"number of processes",
+		nil, nil)
+
+	cpuSecsDesc = prometheus.NewDesc(
+		"nginx_cpu_seconds_total",
+		"Cpu usage in seconds",
+		nil, nil)
+
+	readBytesDesc = prometheus.NewDesc(
+		"nginx_read_bytes_total",
+		"number of bytes read",
+		nil, nil)
+
+	writeBytesDesc = prometheus.NewDesc(
+		"nginx_write_bytes_total",
+		"number of bytes written",
+		nil, nil)
+
+	memResidentbytesDesc = prometheus.NewDesc(
+		"nginx_resident_memory_bytes",
+		"number of bytes of memory in use",
+		nil, nil)
+
+	memVirtualbytesDesc = prometheus.NewDesc(
+		"nginx_virtual_memory_bytes",
+		"number of bytes of memory in use",
+		nil, nil)
+
+	startTimeDesc = prometheus.NewDesc(
+		"nginx_oldest_start_time_seconds",
+		"start time in seconds since 1970/01/01",
+		nil, nil)
+)
+
+type namedProcess struct {
+	scrapeChan chan scrapeRequest
+	*proc.Grouper
+	fs *proc.FS
+}
+
+func NewNamedProcessCollector(children bool, mn common.MatchNamer) (prometheus.Collector, error) {
+	fs, err := proc.NewFS("/proc")
+	if err != nil {
+		return nil, err
+	}
+	p := namedProcess{
+		scrapeChan: make(chan scrapeRequest),
+		Grouper:    proc.NewGrouper(children, mn),
+		fs:         fs,
+	}
+	_, err = p.Update(p.fs.AllProcs())
+	if err != nil {
+		return nil, err
+	}
+
+	go p.start()
+
+	return p, nil
+}
+
+// Describe implements prometheus.Collector.
+func (p namedProcess) Describe(ch chan<- *prometheus.Desc) {
+	ch <- cpuSecsDesc
+	ch <- numprocsDesc
+	ch <- readBytesDesc
+	ch <- writeBytesDesc
+	ch <- memResidentbytesDesc
+	ch <- memVirtualbytesDesc
+	ch <- startTimeDesc
+}
+
+// Collect implements prometheus.Collector.
+func (p namedProcess) Collect(ch chan<- prometheus.Metric) {
+	req := scrapeRequest{results: ch, done: make(chan struct{})}
+	p.scrapeChan <- req
+	<-req.done
+}
+
+func (p namedProcess) start() {
+	for req := range p.scrapeChan {
+		ch := req.results
+		p.scrape(ch)
+		req.done <- struct{}{}
+	}
+}
+
+func (p namedProcess) Stop() {
+	close(p.scrapeChan)
+}
+
+func (p namedProcess) scrape(ch chan<- prometheus.Metric) {
+	_, err := p.Update(p.fs.AllProcs())
+	if err != nil {
+		glog.Warningf("unexpected error obtaining nginx process info: %v", err)
+		return
+	}
+
+	for gname, gcounts := range p.Groups() {
+		ch <- prometheus.MustNewConstMetric(numprocsDesc,
+			prometheus.GaugeValue, float64(gcounts.Procs))
+		ch <- prometheus.MustNewConstMetric(memResidentbytesDesc,
+			prometheus.GaugeValue, float64(gcounts.Memresident))
+		ch <- prometheus.MustNewConstMetric(memVirtualbytesDesc,
+			prometheus.GaugeValue, float64(gcounts.Memvirtual))
+		ch <- prometheus.MustNewConstMetric(startTimeDesc,
+			prometheus.GaugeValue, float64(gcounts.OldestStartTime.Unix()))
+		ch <- prometheus.MustNewConstMetric(cpuSecsDesc,
+			prometheus.CounterValue, gcounts.Cpu)
+		ch <- prometheus.MustNewConstMetric(readBytesDesc,
+			prometheus.CounterValue, float64(gcounts.ReadBytes))
+		ch <- prometheus.MustNewConstMetric(writeBytesDesc,
+			prometheus.CounterValue, float64(gcounts.WriteBytes))
+	}
+}