fix: stabilize nats connection (#889)

Signed-off-by: Yashash H L <[email protected]> Signed-off-by: Vigith Maurice <[email protected]> Co-authored-by: Vigith Maurice <[email protected]>
numaproj · Jul 26, 2023 · 85360f6 · 85360f6
1 parent d4f8f59
commit 85360f6
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Showing 36 changed files with 593 additions and 764 deletions.
diff --git a/pkg/daemon/server/daemon_server.go b/pkg/daemon/server/daemon_server.go
@@ -61,13 +61,24 @@ func NewDaemonServer(pl *v1alpha1.Pipeline, isbSvcType v1alpha1.ISBSvcType) *dae
 
 func (ds *daemonServer) Run(ctx context.Context) error {
 	log := logging.FromContext(ctx)
-	var isbSvcClient isbsvc.ISBService
-	var err error
+	var (
+		isbSvcClient   isbsvc.ISBService
+		err            error
+		natsClientPool *jsclient.ClientPool
+	)
+
+	natsClientPool, err = jsclient.NewClientPool(ctx, jsclient.WithClientPoolSize(1))
+	defer natsClientPool.CloseAll()
+
+	if err != nil {
+		log.Errorw("Failed to get a NATS client pool.", zap.Error(err))
+		return err
+	}
 	switch ds.isbSvcType {
 	case v1alpha1.ISBSvcTypeRedis:
 		isbSvcClient = isbsvc.NewISBRedisSvc(redisclient.NewInClusterRedisClient())
 	case v1alpha1.ISBSvcTypeJetStream:
-		isbSvcClient, err = isbsvc.NewISBJetStreamSvc(ds.pipeline.Name, isbsvc.WithJetStreamClient(jsclient.NewInClusterJetStreamClient()))
+		isbSvcClient, err = isbsvc.NewISBJetStreamSvc(ds.pipeline.Name, isbsvc.WithJetStreamClient(natsClientPool.NextAvailableClient()))
 		if err != nil {
 			log.Errorw("Failed to get an ISB Service client.", zap.Error(err))
 			return err

diff --git a/pkg/forward/forward.go b/pkg/forward/forward.go
@@ -205,6 +205,7 @@ func (isdf *InterStepDataForward) forwardAChunk(ctx context.Context) {
 	// at-least-once semantics for reading, during restart we will have to reprocess all unacknowledged messages. It is the
 	// responsibility of the Read function to do that.
 	readMessages, err := isdf.fromBufferPartition.Read(ctx, isdf.opts.readBatchSize)
+	isdf.opts.logger.Debugw("Read from buffer", zap.String("bufferFrom", isdf.fromBufferPartition.GetName()), zap.Int64("length", int64(len(readMessages))))
 	if err != nil {
 		isdf.opts.logger.Warnw("failed to read fromBufferPartition", zap.Error(err))
 		readMessagesError.With(map[string]string{metrics.LabelVertex: isdf.vertexName, metrics.LabelPipeline: isdf.pipelineName, metrics.LabelPartitionName: isdf.fromBufferPartition.GetName()}).Inc()
@@ -336,6 +337,7 @@ func (isdf *InterStepDataForward) forwardAChunk(ctx context.Context) {
 			isdf.fromBufferPartition.NoAck(ctx, readOffsets)
 			return
 		}
+		isdf.opts.logger.Debugw("writeToBuffers completed")
 	} else {
 		writeOffsets, err = isdf.streamMessage(ctx, dataMessages, processorWM)
 		if err != nil {

diff --git a/pkg/isb/stores/jetstream/reader.go b/pkg/isb/stores/jetstream/reader.go
@@ -25,20 +25,17 @@ import (
 	"time"
 
 	"github.com/nats-io/nats.go"
-	"go.uber.org/zap"
-	"k8s.io/apimachinery/pkg/util/wait"
-
 	"github.com/numaproj/numaflow/pkg/isb"
 	jsclient "github.com/numaproj/numaflow/pkg/shared/clients/nats"
 	"github.com/numaproj/numaflow/pkg/shared/logging"
+	"go.uber.org/zap"
 )
 
 type jetStreamReader struct {
 	name                   string
 	stream                 string
 	subject                string
-	conn                   *jsclient.NatsConn
-	js                     *jsclient.JetStreamContext
+	client                 *jsclient.NATSClient
 	sub                    *nats.Subscription
 	opts                   *readOptions
 	inProgressTickDuration time.Duration
@@ -47,7 +44,7 @@ type jetStreamReader struct {
 }
 
 // NewJetStreamBufferReader is used to provide a new JetStream buffer reader connection
-func NewJetStreamBufferReader(ctx context.Context, client jsclient.JetStreamClient, name, stream, subject string, partitionIdx int32, opts ...ReadOption) (isb.BufferReader, error) {
+func NewJetStreamBufferReader(ctx context.Context, client *jsclient.NATSClient, name, stream, subject string, partitionIdx int32, opts ...ReadOption) (isb.BufferReader, error) {
 	log := logging.FromContext(ctx).With("bufferReader", name).With("stream", stream).With("subject", subject)
 	o := defaultReadOptions()
 	for _, opt := range opts {
@@ -57,82 +54,40 @@ func NewJetStreamBufferReader(ctx context.Context, client jsclient.JetStreamClie
 			}
 		}
 	}
-	result := &jetStreamReader{
+	reader := &jetStreamReader{
 		name:         name,
 		stream:       stream,
 		subject:      subject,
+		client:       client,
 		partitionIdx: partitionIdx,
 		opts:         o,
 		log:          log,
 	}
 
-	connectAndSubscribe := func() (*jsclient.NatsConn, *jsclient.JetStreamContext, *nats.Subscription, error) {
-		conn, err := client.Connect(ctx, jsclient.ReconnectHandler(func(c *jsclient.NatsConn) {
-			if result.js == nil {
-				log.Error("JetStreamContext is nil")
-				return
-			}
-			var e error
-			_ = wait.ExponentialBackoffWithContext(ctx, wait.Backoff{
-				Steps:    5,
-				Duration: 1 * time.Second,
-				Factor:   1.0,
-				Jitter:   0.1,
-			}, func() (bool, error) {
-				var s *nats.Subscription
-				if s, e = result.js.PullSubscribe(subject, stream, nats.Bind(stream, stream)); e != nil {
-					log.Errorw("Failed to re-subscribe to the stream after reconnection, will retry if the limit is not reached", zap.Error(e))
-					return false, nil
-				} else {
-					result.sub = s
-					log.Info("Re-subscribed to the stream successfully")
-					return true, nil
-				}
-			})
-			if e != nil {
-				// Let it panic to start over
-				log.Fatalw("Failed to re-subscribe after retries", zap.Error(e))
-			}
-		}), jsclient.DisconnectErrHandler(func(nc *jsclient.NatsConn, err error) {
-			log.Errorw("Nats JetStream connection lost", zap.Error(err))
-		}))
-		if err != nil {
-			return nil, nil, nil, fmt.Errorf("failed to get nats connection, %w", err)
-		}
-		js, err := conn.JetStream()
-		if err != nil {
-			conn.Close()
-			return nil, nil, nil, fmt.Errorf("failed to get jetstream context, %w", err)
-		}
-		sub, err := js.PullSubscribe(subject, stream, nats.Bind(stream, stream))
-		if err != nil {
-			conn.Close()
-			return nil, nil, nil, fmt.Errorf("failed to subscribe jet stream subject %q, %w", subject, err)
-		}
-		return conn, js, sub, nil
-	}
-
-	conn, js, sub, err := connectAndSubscribe()
+	jsContext, err := reader.client.JetStreamContext()
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("failed to get JetStream context, %w", err)
 	}
 
-	consumer, err := js.ConsumerInfo(stream, stream)
+	consumer, err := jsContext.ConsumerInfo(stream, stream)
 	if err != nil {
-		conn.Close()
 		return nil, fmt.Errorf("failed to get consumer info, %w", err)
 	}
+
 	// If ackWait is 3s, ticks every 2s.
 	inProgessTickSeconds := int64(consumer.Config.AckWait.Seconds() * 2 / 3)
 	if inProgessTickSeconds < 1 {
 		inProgessTickSeconds = 1
 	}
 
-	result.conn = conn
-	result.js = js
-	result.sub = sub
-	result.inProgressTickDuration = time.Duration(inProgessTickSeconds * int64(time.Second))
-	return result, nil
+	sub, err := reader.client.Subscribe(subject, stream, nats.Bind(stream, stream))
+	if err != nil {
+		return nil, fmt.Errorf("failed to subscribe to subject %q, %w", subject, err)
+	}
+
+	reader.sub = sub
+	reader.inProgressTickDuration = time.Duration(inProgessTickSeconds * int64(time.Second))
+	return reader, nil
 }
 
 func (jr *jetStreamReader) GetName() string {
@@ -149,18 +104,11 @@ func (jr *jetStreamReader) Close() error {
 			jr.log.Errorw("Failed to unsubscribe", zap.Error(err))
 		}
 	}
-	if jr.conn != nil && !jr.conn.IsClosed() {
-		jr.conn.Close()
-	}
 	return nil
 }
 
 func (jr *jetStreamReader) Pending(_ context.Context) (int64, error) {
-	c, err := jr.js.ConsumerInfo(jr.stream, jr.stream)
-	if err != nil {
-		return isb.PendingNotAvailable, fmt.Errorf("failed to get consumer info, %w", err)
-	}
-	return int64(c.NumPending) + int64(c.NumAckPending), nil
+	return jr.client.PendingForStream(jr.stream, jr.stream)
 }
 
 func (jr *jetStreamReader) Read(_ context.Context, count int64) ([]*isb.ReadMessage, error) {

diff --git a/pkg/isb/stores/jetstream/reader_test.go b/pkg/isb/stores/jetstream/reader_test.go
@@ -28,7 +28,6 @@ import (
 
 	"github.com/numaproj/numaflow/pkg/isb"
 	"github.com/numaproj/numaflow/pkg/isb/testutils"
-	jsclient "github.com/numaproj/numaflow/pkg/shared/clients/nats"
 	natstest "github.com/numaproj/numaflow/pkg/shared/clients/nats/test"
 )
 
@@ -46,10 +45,8 @@ func TestJetStreamBufferRead(t *testing.T) {
 	defer cancel()
 
 	defaultJetStreamClient := natstest.JetStreamClient(t, s)
-	conn, err := defaultJetStreamClient.Connect(ctx)
-	assert.NoError(t, err)
-	defer conn.Close()
-	js, err := conn.JetStream()
+	defer defaultJetStreamClient.Close()
+	js, err := defaultJetStreamClient.JetStreamContext()
 	assert.NoError(t, err)
 
 	streamName := "testJetStreamBufferReader"
@@ -102,7 +99,7 @@ func TestJetStreamBufferRead(t *testing.T) {
 	}
 	assert.Equal(t, 20, len(offsetsInsideReadMessages))
 
-	fromStepJs, err := fromStep.conn.JetStream()
+	fromStepJs, err := fromStep.client.JetStreamContext()
 	assert.NoError(t, err)
 	streamInfo, err := fromStepJs.StreamInfo(streamName)
 	assert.NoError(t, err)
@@ -141,11 +138,9 @@ func TestGetName(t *testing.T) {
 	defer cancel()
 
 	defaultJetStreamClient := natstest.JetStreamClient(t, s)
-	conn, err := defaultJetStreamClient.Connect(ctx)
-	assert.NoError(t, err)
-	js, err := conn.JetStream()
+	js, err := defaultJetStreamClient.JetStreamContext()
 	assert.NoError(t, err)
-	defer conn.Close()
+	defer defaultJetStreamClient.Close()
 
 	streamName := "getName"
 	addStream(t, js, streamName)
@@ -168,10 +163,8 @@ func TestClose(t *testing.T) {
 	defer cancel()
 
 	defaultJetStreamClient := natstest.JetStreamClient(t, s)
-	conn, err := defaultJetStreamClient.Connect(ctx)
-	assert.NoError(t, err)
-	defer conn.Close()
-	js, err := conn.JetStream()
+	defer defaultJetStreamClient.Close()
+	js, err := defaultJetStreamClient.JetStreamContext()
 	assert.NoError(t, err)
 
 	streamName := "close"
@@ -186,7 +179,7 @@ func TestClose(t *testing.T) {
 
 }
 
-func addStream(t *testing.T, js *jsclient.JetStreamContext, streamName string) {
+func addStream(t *testing.T, js nats.JetStreamContext, streamName string) {
 
 	_, err := js.AddStream(&nats.StreamConfig{
 		Name:       streamName,
@@ -210,7 +203,7 @@ func addStream(t *testing.T, js *jsclient.JetStreamContext, streamName string) {
 
 }
 
-func deleteStream(js *jsclient.JetStreamContext, streamName string) {
+func deleteStream(js nats.JetStreamContext, streamName string) {
 	_ = js.DeleteConsumer(streamName, streamName)
 	_ = js.DeleteStream(streamName)
 }
diff --git a/pkg/isb/stores/jetstream/writer.go b/pkg/isb/stores/jetstream/writer.go
@@ -38,15 +38,15 @@ type jetStreamWriter struct {
 	partitionIdx int32
 	stream       string
 	subject      string
-	conn         *jsclient.NatsConn
-	js           *jsclient.JetStreamContext
+	client       *jsclient.NATSClient
+	js           nats.JetStreamContext
 	opts         *writeOptions
 	isFull       *atomic.Bool
 	log          *zap.SugaredLogger
 }
 
 // NewJetStreamBufferWriter is used to provide a new instance of JetStreamBufferWriter
-func NewJetStreamBufferWriter(ctx context.Context, client jsclient.JetStreamClient, name, stream, subject string, partitionIdx int32, opts ...WriteOption) (isb.BufferWriter, error) {
+func NewJetStreamBufferWriter(ctx context.Context, client *jsclient.NATSClient, name, stream, subject string, partitionIdx int32, opts ...WriteOption) (isb.BufferWriter, error) {
 	o := defaultWriteOptions()
 	for _, opt := range opts {
 		if opt != nil {
@@ -55,14 +55,10 @@ func NewJetStreamBufferWriter(ctx context.Context, client jsclient.JetStreamClie
 			}
 		}
 	}
-	conn, err := client.Connect(ctx)
-	if err != nil {
-		return nil, fmt.Errorf("failed to get nats connection, %w", err)
-	}
 
-	js, err := conn.JetStream(nats.PublishAsyncMaxPending(1024))
+	js, err := client.JetStreamContext(nats.PublishAsyncMaxPending(1024))
+
 	if err != nil {
-		conn.Close()
 		return nil, fmt.Errorf("failed to get JetStream context for writer")
 	}
 
@@ -71,7 +67,7 @@ func NewJetStreamBufferWriter(ctx context.Context, client jsclient.JetStreamClie
 		partitionIdx: partitionIdx,
 		stream:       stream,
 		subject:      subject,
-		conn:         conn,
+		client:       client,
 		js:           js,
 		opts:         o,
 		isFull:       atomic.NewBool(true),
@@ -85,7 +81,7 @@ func NewJetStreamBufferWriter(ctx context.Context, client jsclient.JetStreamClie
 func (jw *jetStreamWriter) runStatusChecker(ctx context.Context) {
 	labels := map[string]string{"buffer": jw.GetName()}
 	// Use a separated JetStream context for status checker
-	js, err := jw.conn.JetStream()
+	js, err := jw.client.JetStreamContext()
 	if err != nil {
 		// Let it exit if it fails to start the status checker
 		jw.log.Fatal("Failed to get Jet Stream context, %w", err)
@@ -150,10 +146,8 @@ func (jw *jetStreamWriter) GetPartitionIdx() int32 {
 	return jw.partitionIdx
 }
 
+// Close doesn't have to do anything for JetStreamBufferWriter, client will be closed by the caller.
 func (jw *jetStreamWriter) Close() error {
-	if jw.conn != nil && !jw.conn.IsClosed() {
-		jw.conn.Close()
-	}
 	return nil
 }