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sinks/sinkManager.go

@@ -37,20 +37,28 @@ type SinkManager interface {
 	Close()
 }
 
+// Init initializes the sink manager by:
+// * Reading its configuration file
+// * Adding the configured sinks and providing them with the corresponding config
 func (sm *sinkManager) Init(wg *sync.WaitGroup, sinkConfigFile string) error {
 	sm.input = nil
 	sm.done = make(chan bool)
 	sm.wg = wg
 	sm.sinks = make(map[string]Sink, 0)
 
+	if len(sinkConfigFile) == 0 {
+		return nil
+	}
+
 	// Read sink config file
-	if len(sinkConfigFile) > 0 {
 	configFile, err := os.Open(sinkConfigFile)
 	if err != nil {
 		cclog.ComponentError("SinkManager", err.Error())
 		return err
 	}
 	defer configFile.Close()
+
+	// Parse config
 	jsonParser := json.NewDecoder(configFile)
 	var rawConfigs map[string]json.RawMessage
 	err = jsonParser.Decode(&rawConfigs)
@@ -58,6 +66,8 @@ func (sm *sinkManager) Init(wg *sync.WaitGroup, sinkConfigFile string) error {
 		cclog.ComponentError("SinkManager", err.Error())
 		return err
 	}
+
+	// Start sinks
 	for name, raw := range rawConfigs {
 		err = sm.AddOutput(name, raw)
 		if err != nil {
@@ -65,10 +75,12 @@ func (sm *sinkManager) Init(wg *sync.WaitGroup, sinkConfigFile string) error {
 			continue
 		}
 	}
-	}
+
 	return nil
 }
 
+// Start starts the sink managers background task, which
+// distributes received metrics to the sinks
 func (sm *sinkManager) Start() {
 	batchcount := 20
 
@@ -156,7 +168,7 @@ func (sm *sinkManager) Close() {
 
 // New creates a new initialized sink manager
 func New(wg *sync.WaitGroup, sinkConfigFile string) (SinkManager, error) {
-	sm := &sinkManager{}
+	sm := new(sinkManager)
 	err := sm.Init(wg, sinkConfigFile)
 	if err != nil {
 		return nil, err