Rename controller to nginx

controllers/nginx/nginx/utils.go

@@ -0,0 +1,173 @@
+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 nginx
+
+import (
+	"bytes"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"reflect"
+	"strings"
+
+	"github.com/golang/glog"
+
+	"github.com/mitchellh/mapstructure"
+	"k8s.io/kubernetes/pkg/api"
+)
+
+// getDNSServers returns the list of nameservers located in the file /etc/resolv.conf
+func getDNSServers() []string {
+	file, err := ioutil.ReadFile("/etc/resolv.conf")
+	if err != nil {
+		return []string{}
+	}
+
+	// Lines of the form "nameserver 1.2.3.4" accumulate.
+	nameservers := []string{}
+
+	lines := strings.Split(string(file), "\n")
+	for l := range lines {
+		trimmed := strings.TrimSpace(lines[l])
+		if strings.HasPrefix(trimmed, "#") {
+			continue
+		}
+		fields := strings.Fields(trimmed)
+		if len(fields) == 0 {
+			continue
+		}
+		if fields[0] == "nameserver" {
+			nameservers = append(nameservers, fields[1:]...)
+		}
+	}
+
+	glog.V(3).Infof("nameservers to use: %v", nameservers)
+	return nameservers
+}
+
+// ReadConfig obtains the configuration defined by the user merged with the defaults.
+func (ngx *Manager) ReadConfig(config *api.ConfigMap) nginxConfiguration {
+	if len(config.Data) == 0 {
+		return newDefaultNginxCfg()
+	}
+
+	cfg := newDefaultNginxCfg()
+
+	decoder, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
+		TagName:          "structs",
+		Result:           &cfg,
+		WeaklyTypedInput: true,
+	})
+
+	err = decoder.Decode(config.Data)
+	if err != nil {
+		glog.Infof("%v", err)
+	}
+
+	return cfg
+}
+
+func (ngx *Manager) needsReload(data *bytes.Buffer) (bool, error) {
+	filename := ngx.ConfigFile
+	in, err := os.Open(filename)
+	if err != nil {
+		return false, err
+	}
+
+	src, err := ioutil.ReadAll(in)
+	in.Close()
+	if err != nil {
+		return false, err
+	}
+
+	res := data.Bytes()
+	if !bytes.Equal(src, res) {
+		err = ioutil.WriteFile(filename, res, 0644)
+		if err != nil {
+			return false, err
+		}
+
+		dData, err := diff(src, res)
+		if err != nil {
+			glog.Errorf("error computing diff: %s", err)
+			return true, nil
+		}
+
+		if glog.V(2) {
+			glog.Infof("NGINX configuration diff a/%s b/%s\n", filename, filename)
+			glog.Infof("%v", string(dData))
+		}
+
+		return len(dData) > 0, nil
+	}
+
+	return false, nil
+}
+
+func diff(b1, b2 []byte) (data []byte, err error) {
+	f1, err := ioutil.TempFile("", "")
+	if err != nil {
+		return
+	}
+	defer os.Remove(f1.Name())
+	defer f1.Close()
+
+	f2, err := ioutil.TempFile("", "")
+	if err != nil {
+		return
+	}
+	defer os.Remove(f2.Name())
+	defer f2.Close()
+
+	f1.Write(b1)
+	f2.Write(b2)
+
+	data, err = exec.Command("diff", "-u", f1.Name(), f2.Name()).CombinedOutput()
+	if len(data) > 0 {
+		err = nil
+	}
+	return
+}
+
+func merge(dst, src map[string]interface{}) map[string]interface{} {
+	for key, srcVal := range src {
+		if dstVal, ok := dst[key]; ok {
+			srcMap, srcMapOk := toMap(srcVal)
+			dstMap, dstMapOk := toMap(dstVal)
+			if srcMapOk && dstMapOk {
+				srcVal = merge(dstMap, srcMap)
+			}
+		}
+		dst[key] = srcVal
+	}
+
+	return dst
+}
+
+func toMap(iface interface{}) (map[string]interface{}, bool) {
+	value := reflect.ValueOf(iface)
+	if value.Kind() == reflect.Map {
+		m := map[string]interface{}{}
+		for _, k := range value.MapKeys() {
+			m[k.String()] = value.MapIndex(k).Interface()
+		}
+
+		return m, true
+	}
+
+	return map[string]interface{}{}, false
+}