DRY up the closure

producer.go

@@ -332,6 +332,18 @@ func (p *Producer) leaderDispatcher(topic string, partition int32, input chan *M
 	var output chan *MessageToSend
 	var backlog []*MessageToSend
 	breaker := breaker.New(3, 1, 10*time.Second)
+	doUpdate := func() (err error) {
+		if err = p.client.RefreshTopicMetadata(topic); err != nil {
+			return err
+		}
+
+		if leader, err = p.client.Leader(topic, partition); err != nil {
+			return err
+		}
+
+		output = p.getBrokerWorker(leader)
+		return nil
+	}
 
 	// try to prefetch the leader; if this doesn't work, we'll do a proper breaker-protected refresh-and-fetch
 	// on the first message
@@ -362,12 +374,7 @@ func (p *Producer) leaderDispatcher(topic string, partition int32, input chan *M
 			// retry *and* chaser flag set, flush the backlog and return to normal processing
 			Logger.Printf("producer/leader state change to [flushing] on %s/%d\n", topic, partition)
 			if output == nil {
-				err := breaker.Run(func() (err error) {
-					leader, output, err = p.updateLeaderAndWorker(topic, partition)
-					return err
-				})
-
-				if err != nil {
+				if err := breaker.Run(doUpdate); err != nil {
 					p.returnErrors(backlog, err)
 					backlog = nil
 					continue
@@ -384,12 +391,7 @@ func (p *Producer) leaderDispatcher(topic string, partition int32, input chan *M
 		}
 
 		if output == nil {
-			err := breaker.Run(func() (err error) {
-				leader, output, err = p.updateLeaderAndWorker(topic, partition)
-				return err
-			})
-
-			if err != nil {
+			if err := breaker.Run(doUpdate); err != nil {
 				p.returnError(msg, err)
 				continue
 			}
@@ -785,17 +787,3 @@ func (p *Producer) unrefBrokerWorker(broker *Broker) {
 		}
 	}
 }
-
-func (p *Producer) updateLeaderAndWorker(topic string, partition int32) (leader *Broker, worker chan *MessageToSend, err error) {
-	if err = p.client.RefreshTopicMetadata(topic); err != nil {
-		return nil, nil, err
-	}
-
-	if leader, err = p.client.Leader(topic, partition); err != nil {
-		return nil, nil, err
-	}
-
-	worker = p.getBrokerWorker(leader)
-
-	return leader, worker, nil
-}