Place wait group Add() and Done() near to each other

collectors/collectorManager.go

@@ -102,18 +102,18 @@ func (cm *collectorManager) Init(ticker mct.MultiChanTicker, duration time.Durat
 
 // Start starts the metric collector manager
 func (cm *collectorManager) Start() {
-	cm.wg.Add(1)
 	tick := make(chan time.Time)
 	cm.ticker.AddChannel(tick)
 
+	cm.wg.Add(1)
 	go func() {
+		defer cm.wg.Done()
 		// Collector manager is done
 		done := func() {
 			// close all metric collectors
 			for _, c := range cm.collectors {
 				c.Close()
 			}
-			cm.wg.Done()
 			cclog.ComponentDebug("CollectorManager", "DONE")
 		}
 

internal/metricRouter/metricRouter.go

@@ -80,7 +80,10 @@ func (r *metricRouter) StartTimer() {
 	m := make(chan time.Time)
 	r.ticker.AddChannel(m)
 	r.timerdone = make(chan bool)
+
+	r.wg.Add(1)
 	go func() {
+		defer r.wg.Done()
 		for {
 			select {
 			case <-r.timerdone:
@@ -169,13 +172,11 @@ func (r *metricRouter) DoDelTags(point lp.CCMetric) {
 
 // Start starts the metric router
 func (r *metricRouter) Start() {
-	r.wg.Add(1)
 	r.timestamp = time.Now()
 	if r.config.IntervalStamp {
 		r.StartTimer()
 	}
 	done := func() {
-		r.wg.Done()
 		cclog.ComponentDebug("MetricRouter", "DONE")
 	}
 	forward := func(point lp.CCMetric) {
@@ -186,7 +187,10 @@ func (r *metricRouter) Start() {
 			o <- point
 		}
 	}
+
+	r.wg.Add(1)
 	go func() {
+		defer r.wg.Done()
 		for {
 			//		RouterLoop:
 			select {

metric-collector.go

@@ -51,25 +51,16 @@ type RuntimeConfig struct {
 	CliArgs    map[string]string
 	ConfigFile CentralConfigFile
 
-	Router         mr.MetricRouter
+	MetricRouter    mr.MetricRouter
 	CollectManager  collectors.CollectorManager
 	SinkManager     sinks.SinkManager
 	ReceiveManager  receivers.ReceiveManager
-	Ticker         mct.MultiChanTicker
+	MultiChanTicker mct.MultiChanTicker
 
 	Channels []chan lp.CCMetric
 	Sync     sync.WaitGroup
 }
 
-func prepare_runcfg() RuntimeConfig {
-	return RuntimeConfig{
-		Router:         nil,
-		CollectManager: nil,
-		SinkManager:    nil,
-		ReceiveManager: nil,
-	}
-}
-
 //// Structure of the configuration file
 //type GlobalConfig struct {
 //	Sink           sinks.SinkConfig           `json:"sink"`
@@ -157,8 +148,9 @@ func ReadCli() map[string]string {
 
 // General shutdownHandler function that gets executed in case of interrupt or graceful shutdownHandler
 func shutdownHandler(config *RuntimeConfig, shutdownSignal chan os.Signal) {
-	<-shutdownSignal
+	defer config.Sync.Done()
 
+	<-shutdownSignal
 	// Remove shutdown handler
 	// every additional interrupt signal will stop without cleaning up
 	signal.Stop(shutdownSignal)
@@ -166,7 +158,7 @@ func shutdownHandler(config *RuntimeConfig, shutdownSignal chan os.Signal) {
 	cclog.Info("Shutdown...")
 
 	cclog.Debug("Shutdown Ticker...")
-	config.Ticker.Close()
+	config.MultiChanTicker.Close()
 
 	if config.CollectManager != nil {
 		cclog.Debug("Shutdown CollectManager...")
@@ -176,9 +168,9 @@ func shutdownHandler(config *RuntimeConfig, shutdownSignal chan os.Signal) {
 		cclog.Debug("Shutdown ReceiveManager...")
 		config.ReceiveManager.Close()
 	}
-	if config.Router != nil {
+	if config.MetricRouter != nil {
 		cclog.Debug("Shutdown Router...")
-		config.Router.Close()
+		config.MetricRouter.Close()
 	}
 	if config.SinkManager != nil {
 		cclog.Debug("Shutdown SinkManager...")
@@ -189,15 +181,20 @@ func shutdownHandler(config *RuntimeConfig, shutdownSignal chan os.Signal) {
 	//	RemovePidfile(pidfile)
 	//	pidfile = config.CliArgs["pidfile"]
 	//	RemovePidfile(pidfile)
-	config.Sync.Done()
 }
 
 func mainFunc() int {
 	var err error
 	use_recv := false
 
-	rcfg := prepare_runcfg()
-	rcfg.CliArgs = ReadCli()
+	// Initialize runtime configuration
+	rcfg := RuntimeConfig{
+		MetricRouter:   nil,
+		CollectManager: nil,
+		SinkManager:    nil,
+		ReceiveManager: nil,
+		CliArgs:        ReadCli(),
+	}
 
 	// Load and check configuration
 	err = LoadCentralConfiguration(rcfg.CliArgs["configfile"], &rcfg.ConfigFile)
@@ -225,61 +222,75 @@ func mainFunc() int {
 	rcfg.Hostname = strings.SplitN(rcfg.Hostname, `.`, 2)[0]
 	//	err = CreatePidfile(rcfg.CliArgs["pidfile"])
 
-	if rcfg.CliArgs["logfile"] != "stderr" {
-		cclog.SetOutput(rcfg.CliArgs["logfile"])
+	// Set log file
+	if logfile := rcfg.CliArgs["logfile"]; logfile != "stderr" {
+		cclog.SetOutput(logfile)
 	}
-	//	err = SetLogging(rcfg.CliArgs["logfile"])
-	//	if err != nil {
-	//		log.Print("Error setting up logging system to ", rcfg.CliArgs["logfile"], " on ", rcfg.Hostname)
-	//		return
-	//	}
-	rcfg.Ticker = mct.NewTicker(rcfg.Interval)
+
+	// Creat new multi channel ticker
+	rcfg.MultiChanTicker = mct.NewTicker(rcfg.Interval)
+
+	// Create new metric router
 	if len(rcfg.ConfigFile.RouterConfigFile) > 0 {
-		rcfg.Router, err = mr.New(rcfg.Ticker, &rcfg.Sync, rcfg.ConfigFile.RouterConfigFile)
+		rcfg.MetricRouter, err = mr.New(rcfg.MultiChanTicker, &rcfg.Sync, rcfg.ConfigFile.RouterConfigFile)
 		if err != nil {
 			cclog.Error(err.Error())
 			return 1
 		}
 	}
+
+	// Create new sink
 	if len(rcfg.ConfigFile.SinkConfigFile) > 0 {
 		rcfg.SinkManager, err = sinks.New(&rcfg.Sync, rcfg.ConfigFile.SinkConfigFile)
 		if err != nil {
 			cclog.Error(err.Error())
 			return 1
 		}
+
+		// Connect metric router to sink manager
 		RouterToSinksChannel := make(chan lp.CCMetric, 200)
 		rcfg.SinkManager.AddInput(RouterToSinksChannel)
-		rcfg.Router.AddOutput(RouterToSinksChannel)
+		rcfg.MetricRouter.AddOutput(RouterToSinksChannel)
 	}
+
+	// Create new collector manager
 	if len(rcfg.ConfigFile.CollectorConfigFile) > 0 {
-		rcfg.CollectManager, err = collectors.New(rcfg.Ticker, rcfg.Duration, &rcfg.Sync, rcfg.ConfigFile.CollectorConfigFile)
+		rcfg.CollectManager, err = collectors.New(rcfg.MultiChanTicker, rcfg.Duration, &rcfg.Sync, rcfg.ConfigFile.CollectorConfigFile)
 		if err != nil {
 			cclog.Error(err.Error())
 			return 1
 		}
+
+		// Connect collector manager to metric router
 		CollectToRouterChannel := make(chan lp.CCMetric, 200)
 		rcfg.CollectManager.AddOutput(CollectToRouterChannel)
-		rcfg.Router.AddCollectorInput(CollectToRouterChannel)
+		rcfg.MetricRouter.AddCollectorInput(CollectToRouterChannel)
 	}
+
+	// Create new receive manager
 	if len(rcfg.ConfigFile.ReceiverConfigFile) > 0 {
 		rcfg.ReceiveManager, err = receivers.New(&rcfg.Sync, rcfg.ConfigFile.ReceiverConfigFile)
 		if err != nil {
 			cclog.Error(err.Error())
 			return 1
 		}
+
+		// Connect receive manager to metric router
 		ReceiveToRouterChannel := make(chan lp.CCMetric, 200)
 		rcfg.ReceiveManager.AddOutput(ReceiveToRouterChannel)
-		rcfg.Router.AddReceiverInput(ReceiveToRouterChannel)
+		rcfg.MetricRouter.AddReceiverInput(ReceiveToRouterChannel)
 		use_recv = true
 	}
 
+	// Create shutdown handler
 	shutdownSignal := make(chan os.Signal, 1)
 	signal.Notify(shutdownSignal, os.Interrupt)
 	signal.Notify(shutdownSignal, syscall.SIGTERM)
+	rcfg.Sync.Add(1)
 	go shutdownHandler(&rcfg, shutdownSignal)
 
-	rcfg.Sync.Add(1)
-	rcfg.Router.Start()
+	// Start the managers
+	rcfg.MetricRouter.Start()
 	rcfg.SinkManager.Start()
 	rcfg.CollectManager.Start()
 
@@ -294,8 +305,9 @@ func mainFunc() int {
 		shutdownSignal <- os.Interrupt
 	}
 
-	// Wait until shutdownHandler is executed
+	// Wait that all goroutines finish
 	rcfg.Sync.Wait()
+
 	return 0
 }