Fix data race when accessing partition producer state (#215)

Fix data race when accessing partition producer state

pulsar/producer_partition.go

@@ -31,17 +31,16 @@ import (
 	"github.com/apache/pulsar-client-go/pulsar/internal/pb"
 )
 
-type producerState int
-
 const (
-	producerInit producerState = iota
+	// producer states
+	producerInit int32 = iota
 	producerReady
 	producerClosing
 	producerClosed
 )
 
 type partitionProducer struct {
-	state  producerState
+	state  int32
 	client *client
 	topic  string
 	log    *log.Entry
@@ -107,7 +106,7 @@ func newPartitionProducer(client *client, topic string, options *ProducerOptions
 
 	p.log = p.log.WithField("producer_name", p.producerName)
 	p.log.WithField("cnx", p.cnx.ID()).Info("Created producer")
-	p.state = producerReady
+	atomic.StoreInt32(&p.state, producerReady)
 
 	go p.runEventsLoop()
 
@@ -181,7 +180,7 @@ func (p *partitionProducer) ConnectionClosed() {
 func (p *partitionProducer) reconnectToBroker() {
 	backoff := internal.Backoff{}
 	for {
-		if p.state != producerReady {
+		if atomic.LoadInt32(&p.state) != producerReady {
 			// Producer is already closing
 			return
 		}
@@ -439,11 +438,10 @@ func (p *partitionProducer) ReceivedSendReceipt(response *pb.CommandSendReceipt)
 
 func (p *partitionProducer) internalClose(req *closeProducer) {
 	defer req.waitGroup.Done()
-	if p.state != producerReady {
+	if !atomic.CompareAndSwapInt32(&p.state, producerReady, producerClosing) {
 		return
 	}
 
-	p.state = producerClosing
 	p.log.Info("Closing producer")
 
 	id := p.client.rpcClient.NewRequestID()
@@ -458,7 +456,7 @@ func (p *partitionProducer) internalClose(req *closeProducer) {
 		p.log.Info("Closed producer")
 	}
 
-	p.state = producerClosed
+	atomic.StoreInt32(&p.state, producerClosed)
 	p.cnx.UnregisterListener(p.producerID)
 	p.batchFlushTicker.Stop()
 }
@@ -479,7 +477,7 @@ func (p *partitionProducer) Flush() error {
 }
 
 func (p *partitionProducer) Close() {
-	if p.state != producerReady {
+	if atomic.LoadInt32(&p.state) != producerReady {
 		// Producer is closing
 		return
 	}