Allow notifications prefixes

Could be useful when you have, for instance, several
clusters, and want to convey the current cluster with
the alerts notifications.

README.md

@@ -28,7 +28,7 @@ provide this server's address with "-s" flag, or a kube config with "-k").
 You can pass configuration values either by command line arguments, or
 environment variables, a yaml configuration file, or a combination or those.
 
-The command line flags are:
+The command line flags are (all optionals):
 ```
 Usage:
   kube-alert [flags]
@@ -45,13 +45,15 @@ Flags:
   -v, --log-level string         log level (default "debug")
   -l, --log-output string        log output (default "stderr")
   -r, --log-server string        log server (if using syslog)
+  -m, --messages-prefix string   prefix appended to notifications
 ```
 
 Using an (optional) configuration file:
 ```yaml
 dry-run: false
 healthcheck-port: 8080
 api-server: http://example.com:8080
+messages-prefix: kube-prod-cluster-42
 
 log:
   output: "stdout"

cmd/execute.go

@@ -28,6 +28,7 @@ var (
 	ddApiKey  string
 	ddAppKey  string
 	healthP   int
+	msgPrefix string
 
 	// rootCmd represents the base command when called without any subcommands
 	rootCmd = &cobra.Command{
@@ -42,6 +43,7 @@ var (
 				DdAppKey:   viper.GetString("datadog.app-key"),
 				DdApiKey:   viper.GetString("datadog.api-key"),
 				HealthPort: viper.GetInt("healthcheck-port"),
+				MsgPrefix:  viper.GetString("messages-prefix"),
 			}
 			config.Init(viper.GetString("api-server"), viper.GetString("kube-config"))
 			run.Run(config)
@@ -109,6 +111,11 @@ func init() {
 	if err := viper.BindPFlag("healthcheck-port", rootCmd.PersistentFlags().Lookup("healthcheck-port")); err != nil {
 		log.Fatal("Failed to bind cli argument:", err)
 	}
+
+	rootCmd.PersistentFlags().StringVarP(&msgPrefix, "messages-prefix", "m", "", "prefix appended to notifications")
+	if err := viper.BindPFlag("messages-prefix", rootCmd.PersistentFlags().Lookup("messages-prefix")); err != nil {
+		log.Fatal("Failed to bind cli argument:", err)
+	}
 }
 
 func initConfig() {

config/config.go

@@ -16,6 +16,7 @@ type AlertConfig struct {
 	DdAppKey   string
 	DdApiKey   string
 	HealthPort int
+	MsgPrefix  string
 }
 
 func (c *AlertConfig) Init(apiserver string, kubeconfig string) {

pkg/controllers/controllers.go

@@ -62,7 +62,7 @@ func (c *CommonController) Stop() {
 	c.Conf.Logger.Infof("Stopping %s controller", c.Name)
 	close(c.StopCh)
 
-	// give everything 2 seconds to stop gracefully
+	// give everything 2s max to stop gracefully
 	time.Sleep(2 * time.Second)
 	c.wg.Done()
 }

pkg/log/log.go

@@ -47,14 +47,14 @@ func New(logLevel string, logServer string, logOutput string) *logrus.Logger {
 		level = logrus.InfoLevel
 	}
 
-	formater := &logrus.TextFormatter{
+	formatter := &logrus.TextFormatter{
 		FullTimestamp:   true,
 		TimestampFormat: "2006-01-02 15:04:05",
 	}
 
 	log := &logrus.Logger{
 		Out:       output,
-		Formatter: formater,
+		Formatter: formatter,
 		Hooks:     make(logrus.LevelHooks),
 		Level:     level,
 	}

pkg/notifiers/notifiers.go

@@ -18,13 +18,18 @@ var Notifiers = []Notifier{
 }
 
 func Notify(c *config.AlertConfig, title string, msg string) {
+	ptitle := title
+	if c.MsgPrefix != "" {
+		ptitle = fmt.Sprintf("%s %s", c.MsgPrefix, title)
+	}
+
 	if c.DryRun {
-		fmt.Printf("%s: %s\n", title, msg)
+		fmt.Printf("%s: %s\n", ptitle, msg)
 		return
 	}
 
 	for _, notifier := range Notifiers {
-		err := notifier.Notify(c, title, msg)
+		err := notifier.Notify(c, ptitle, msg)
 		if err != nil {
 			c.Logger.Warningf("Failed to notify: %s", err)
 		}