event: use common initialization logic (#3798)

Previously creating and adding targets for each notification type was
repeated.  This patch fixes it.

cmd/event-notifier.go

@@ -537,6 +537,28 @@ func loadAllBucketNotifications(objAPI ObjectLayer) (map[string]*notificationCon
 	return nConfigs, lConfigs, nil
 }
 
+// addQueueTarget - calls newTargetFunc function and adds its returned value to queueTargets
+func addQueueTarget(queueTargets map[string]*logrus.Logger,
+	accountID, queueType string,
+	newTargetFunc func(string) (*logrus.Logger, error)) (string, error) {
+
+	// Construct the queue ARN for AMQP.
+	queueARN := minioSqs + serverConfig.GetRegion() + ":" + accountID + ":" + queueType
+
+	// Queue target if already initialized we move to the next ARN.
+	if _, ok := queueTargets[queueARN]; ok {
+		return queueARN, nil
+	}
+
+	// Using accountID we can now initialize a new AMQP logrus instance.
+	logger, err := newTargetFunc(accountID)
+	if err == nil {
+		queueTargets[queueARN] = logger
+	}
+
+	return queueARN, err
+}
+
 // Loads all queue targets, initializes each queueARNs depending on their config.
 // Each instance of queueARN registers its own logrus to communicate with the
 // queue service. QueueARN once initialized is not initialized again for the
@@ -548,54 +570,37 @@ func loadAllQueueTargets() (map[string]*logrus.Logger, error) {
 		if !amqpN.Enable {
 			continue
 		}
-		// Construct the queue ARN for AMQP.
-		queueARN := minioSqs + serverConfig.GetRegion() + ":" + accountID + ":" + queueTypeAMQP
-		// Queue target if already initialized we move to the next ARN.
-		_, ok := queueTargets[queueARN]
-		if ok {
-			continue
-		}
-		// Using accountID we can now initialize a new AMQP logrus instance.
-		amqpLog, err := newAMQPNotify(accountID)
-		if err != nil {
-			// Encapsulate network error to be more informative.
+
+		if queueARN, err := addQueueTarget(queueTargets, accountID, queueTypeAMQP, newAMQPNotify); err != nil {
 			if _, ok := err.(net.Error); ok {
-				return nil, &net.OpError{
+				err = &net.OpError{
 					Op:  "Connecting to " + queueARN,
 					Net: "tcp",
 					Err: err,
 				}
 			}
+
 			return nil, err
 		}
-		queueTargets[queueARN] = amqpLog
 	}
+
 	// Load all nats targets, initialize their respective loggers.
 	for accountID, natsN := range serverConfig.Notify.GetNATS() {
 		if !natsN.Enable {
 			continue
 		}
-		// Construct the queue ARN for NATS.
-		queueARN := minioSqs + serverConfig.GetRegion() + ":" + accountID + ":" + queueTypeNATS
-		// Queue target if already initialized we move to the next ARN.
-		_, ok := queueTargets[queueARN]
-		if ok {
-			continue
-		}
-		// Using accountID we can now initialize a new NATS logrus instance.
-		natsLog, err := newNATSNotify(accountID)
-		if err != nil {
-			// Encapsulate network error to be more informative.
+
+		if queueARN, err := addQueueTarget(queueTargets, accountID, queueTypeNATS, newNATSNotify); err != nil {
 			if _, ok := err.(net.Error); ok {
-				return nil, &net.OpError{
+				err = &net.OpError{
 					Op:  "Connecting to " + queueARN,
 					Net: "tcp",
 					Err: err,
 				}
 			}
+
 			return nil, err
 		}
-		queueTargets[queueARN] = natsLog
 	}
 
 	// Load redis targets, initialize their respective loggers.
@@ -603,27 +608,18 @@ func loadAllQueueTargets() (map[string]*logrus.Logger, error) {
 		if !redisN.Enable {
 			continue
 		}
-		// Construct the queue ARN for Redis.
-		queueARN := minioSqs + serverConfig.GetRegion() + ":" + accountID + ":" + queueTypeRedis
-		// Queue target if already initialized we move to the next ARN.
-		_, ok := queueTargets[queueARN]
-		if ok {
-			continue
-		}
-		// Using accountID we can now initialize a new Redis logrus instance.
-		redisLog, err := newRedisNotify(accountID)
-		if err != nil {
-			// Encapsulate network error to be more informative.
+
+		if queueARN, err := addQueueTarget(queueTargets, accountID, queueTypeRedis, newRedisNotify); err != nil {
 			if _, ok := err.(net.Error); ok {
-				return nil, &net.OpError{
+				err = &net.OpError{
 					Op:  "Connecting to " + queueARN,
 					Net: "tcp",
 					Err: err,
 				}
 			}
+
 			return nil, err
 		}
-		queueTargets[queueARN] = redisLog
 	}
 
 	// Load Webhook targets, initialize their respective loggers.
@@ -631,20 +627,10 @@ func loadAllQueueTargets() (map[string]*logrus.Logger, error) {
 		if !webhookN.Enable {
 			continue
 		}
-		// Construct the queue ARN for Webhook.
-		queueARN := minioSqs + serverConfig.GetRegion() + ":" + accountID + ":" + queueTypeWebhook
-		_, ok := queueTargets[queueARN]
-		if ok {
-			continue
-		}
-
-		// Using accountID we can now initialize a new Webhook logrus instance.
-		webhookLog, err := newWebhookNotify(accountID)
-		if err != nil {
 
+		if _, err := addQueueTarget(queueTargets, accountID, queueTypeWebhook, newWebhookNotify); err != nil {
 			return nil, err
 		}
-		queueTargets[queueARN] = webhookLog
 	}
 
 	// Load elastic targets, initialize their respective loggers.
@@ -652,25 +638,18 @@ func loadAllQueueTargets() (map[string]*logrus.Logger, error) {
 		if !elasticN.Enable {
 			continue
 		}
-		// Construct the queue ARN for Elastic.
-		queueARN := minioSqs + serverConfig.GetRegion() + ":" + accountID + ":" + queueTypeElastic
-		_, ok := queueTargets[queueARN]
-		if ok {
-			continue
-		}
-		// Using accountID we can now initialize a new ElasticSearch logrus instance.
-		elasticLog, err := newElasticNotify(accountID)
-		if err != nil {
-			// Encapsulate network error to be more informative.
+
+		if queueARN, err := addQueueTarget(queueTargets, accountID, queueTypeElastic, newElasticNotify); err != nil {
 			if _, ok := err.(net.Error); ok {
-				return nil, &net.OpError{
-					Op: "Connecting to " + queueARN, Net: "tcp",
+				err = &net.OpError{
+					Op:  "Connecting to " + queueARN,
+					Net: "tcp",
 					Err: err,
 				}
 			}
+
 			return nil, err
 		}
-		queueTargets[queueARN] = elasticLog
 	}
 
 	// Load PostgreSQL targets, initialize their respective loggers.
@@ -678,50 +657,37 @@ func loadAllQueueTargets() (map[string]*logrus.Logger, error) {
 		if !pgN.Enable {
 			continue
 		}
-		// Construct the queue ARN for Postgres.
-		queueARN := minioSqs + serverConfig.GetRegion() + ":" + accountID + ":" + queueTypePostgreSQL
-		_, ok := queueTargets[queueARN]
-		if ok {
-			continue
-		}
-		// Using accountID initialize a new Postgresql logrus instance.
-		pgLog, err := newPostgreSQLNotify(accountID)
-		if err != nil {
-			// Encapsulate network error to be more informative.
+
+		if queueARN, err := addQueueTarget(queueTargets, accountID, queueTypePostgreSQL, newPostgreSQLNotify); err != nil {
 			if _, ok := err.(net.Error); ok {
-				return nil, &net.OpError{
-					Op: "Connecting to " + queueARN, Net: "tcp",
+				err = &net.OpError{
+					Op:  "Connecting to " + queueARN,
+					Net: "tcp",
 					Err: err,
 				}
 			}
+
 			return nil, err
 		}
-		queueTargets[queueARN] = pgLog
 	}
+
 	// Load Kafka targets, initialize their respective loggers.
 	for accountID, kafkaN := range serverConfig.Notify.GetKafka() {
 		if !kafkaN.Enable {
 			continue
 		}
-		// Construct the queue ARN for Kafka.
-		queueARN := minioSqs + serverConfig.GetRegion() + ":" + accountID + ":" + queueTypeKafka
-		_, ok := queueTargets[queueARN]
-		if ok {
-			continue
-		}
-		// Using accountID initialize a new Kafka logrus instance.
-		kafkaLog, err := newKafkaNotify(accountID)
-		if err != nil {
-			// Encapsulate network error to be more informative.
+
+		if queueARN, err := addQueueTarget(queueTargets, accountID, queueTypeKafka, newKafkaNotify); err != nil {
 			if _, ok := err.(net.Error); ok {
-				return nil, &net.OpError{
-					Op: "Connecting to " + queueARN, Net: "tcp",
+				err = &net.OpError{
+					Op:  "Connecting to " + queueARN,
+					Net: "tcp",
 					Err: err,
 				}
 			}
+
 			return nil, err
 		}
-		queueTargets[queueARN] = kafkaLog
 	}
 
 	// Successfully initialized queue targets.