[Fix] Fix the key-based batch can't guarantee the ordering when flush…

…ing (#1252)

### Motivation

When using key-based producing, the key-based batcher cannot guarantee the sequence ID order when flushing messages. This leads to frequent disconnections between the client and the broker, resulting in poor performance.

Here is the related log:
```
time="2024-07-19T03:38:07Z" level=warning msg="Received send error from server: [PersistenceError] : [Cannot determine whether the message is a duplicate at this time]"
time="2024-07-19T03:38:07Z" level=warning msg="Connection was closed" cnx="xxx" producerID=1 producer_name=xxx topic="xxx"
time="2024-07-19T03:38:07Z" level=warning msg="Failed to write on connection" error="use of closed network connection" local_addr="xxx" remote_addr="xxx"
```

The broker receives unordered messages and returns a SendError to the client. This causes the client to reconnect to the broker.

### Modifications

- Refactor the BatchBuilder interface.
- Sort batches before flushing in the key-based batcher builder.

(cherry picked from commit e2fd4c9)

pulsar/internal/batch_builder.go

@@ -57,13 +57,11 @@ type BatchBuilder interface {
  ) bool
 
  // Flush all the messages buffered in the client and wait until all messages have been successfully persisted.
- Flush() (batchData Buffer, sequenceID uint64, callbacks []interface{}, err error)
+ Flush() *FlushBatch
 
- // Flush all the messages buffered in multiple batches and wait until all
+ // FlushBatches all the messages buffered in multiple batches and wait until all
  // messages have been successfully persisted.
- FlushBatches() (
- batchData []Buffer, sequenceID []uint64, callbacks [][]interface{}, errors []error,
- )
+ FlushBatches() []*FlushBatch
 
  // Return the batch container batch message in multiple batches.
  IsMultiBatches() bool
@@ -72,6 +70,13 @@ type BatchBuilder interface {
  Close() error
 }
 
+type FlushBatch struct {
+ BatchData Buffer
+ SequenceID uint64
+ Callbacks []interface{}
+ Error error
+}
+
 // batchContainer wraps the objects needed to a batch.
 // batchContainer implement BatchBuilder as a single batch container.
 type batchContainer struct {
@@ -250,12 +255,10 @@ func (bc *batchContainer) reset() {
 }
 
 // Flush all the messages buffered in the client and wait until all messages have been successfully persisted.
-func (bc *batchContainer) Flush() (
- batchData Buffer, sequenceID uint64, callbacks []interface{}, err error,
-) {
+func (bc *batchContainer) Flush() *FlushBatch {
  if bc.numMessages == 0 {
  // No-Op for empty batch
- return nil, 0, nil, nil
+ return nil
  }
 
  bc.log.Debug("BatchBuilder flush: messages: ", bc.numMessages)
@@ -271,22 +274,27 @@ func (bc *batchContainer) Flush() (
  buffer = NewBuffer(int(uncompressedSize * 3 / 2))
  }
 
+ sequenceID := uint64(0)
+ var err error
  if err = serializeMessage(
  buffer, bc.cmdSend, bc.msgMetadata, bc.buffer, bc.compressionProvider,
  bc.encryptor, bc.maxMessageSize, true,
  ); err == nil { // no error in serializing Batch
  sequenceID = bc.cmdSend.Send.GetSequenceId()
  }
 
- callbacks = bc.callbacks
+ callbacks := bc.callbacks
  bc.reset()
- return buffer, sequenceID, callbacks, err
+ return &FlushBatch{
+ BatchData: buffer,
+ SequenceID: sequenceID,
+ Callbacks: callbacks,
+ Error: err,
+ }
 }
 
 // FlushBatches only for multiple batches container
-func (bc *batchContainer) FlushBatches() (
- batchData []Buffer, sequenceID []uint64, callbacks [][]interface{}, errors []error,
-) {
+func (bc *batchContainer) FlushBatches() []*FlushBatch {
  panic("single batch container not support FlushBatches(), please use Flush() instead")
 }
 

pulsar/internal/key_based_batch_builder.go

@@ -191,51 +191,35 @@ func (bc *keyBasedBatchContainer) reset() {
  bc.batches.containers = map[string]*batchContainer{}
 }
 
-// Flush all the messages buffered in multiple batches and wait until all
+// FlushBatches all the messages buffered in multiple batches and wait until all
 // messages have been successfully persisted.
-func (bc *keyBasedBatchContainer) FlushBatches() (
- batchesData []Buffer, sequenceIDs []uint64, callbacks [][]interface{}, errors []error,
-) {
+func (bc *keyBasedBatchContainer) FlushBatches() []*FlushBatch {
  if bc.numMessages == 0 {
  // No-Op for empty batch
- return nil, nil, nil, nil
+ return nil
  }
 
  bc.log.Debug("keyBasedBatchContainer flush: messages: ", bc.numMessages)
- var batchesLen = len(bc.batches.containers)
- var idx = 0
- sortedKeys := make([]string, 0, batchesLen)
-
- batchesData = make([]Buffer, batchesLen)
- sequenceIDs = make([]uint64, batchesLen)
- callbacks = make([][]interface{}, batchesLen)
- errors = make([]error, batchesLen)
-
  bc.batches.l.RLock()
  defer bc.batches.l.RUnlock()
- for k := range bc.batches.containers {
- sortedKeys = append(sortedKeys, k)
- }
- sort.Strings(sortedKeys)
- for _, k := range sortedKeys {
- container := bc.batches.containers[k]
- b, s, c, err := container.Flush()
- if b != nil {
- batchesData[idx] = b
- sequenceIDs[idx] = s
- callbacks[idx] = c
- errors[idx] = err
+ flushBatches := make([]*FlushBatch, 0, len(bc.batches.containers))
+ for _, container := range bc.batches.containers {
+ batch := container.Flush()
+ if batch == nil {
+ continue
  }
- idx++
+ flushBatches = append(flushBatches, batch)
  }
 
  bc.reset()
- return batchesData, sequenceIDs, callbacks, errors
+ // Sort items by sequenceID
+ sort.Slice(flushBatches, func(i, j int) bool {
+ return flushBatches[i].SequenceID < flushBatches[j].SequenceID
+ })
+ return flushBatches
 }
 
-func (bc *keyBasedBatchContainer) Flush() (
- batchData Buffer, sequenceID uint64, callbacks []interface{}, err error,
-) {
+func (bc *keyBasedBatchContainer) Flush() *FlushBatch {
  panic("multi batches container not support Flush(), please use FlushBatches() instead")
 }
 

pulsar/internal/key_based_batch_builder_test.go

@@ -0,0 +1,80 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package internal
+
+import (
+ "fmt"
+ "testing"
+ "time"
+
+ "github.com/apache/pulsar-client-go/pulsar/internal/compression"
+ pb "github.com/apache/pulsar-client-go/pulsar/internal/pulsar_proto"
+ "github.com/apache/pulsar-client-go/pulsar/log"
+ "github.com/sirupsen/logrus"
+ "github.com/stretchr/testify/assert"
+ "google.golang.org/protobuf/proto"
+)
+
+type mockBufferPool struct {
+}
+
+func (m *mockBufferPool) GetBuffer() Buffer {
+ return nil
+}
+
+type mockEncryptor struct {
+}
+
+func (m *mockEncryptor) Encrypt(_ []byte, _ *pb.MessageMetadata) ([]byte, error) {
+ return []byte("test"), nil
+}
+
+func TestKeyBasedBatcherOrdering(t *testing.T) {
+ keyBatcher, err := NewKeyBasedBatchBuilder(
+ 1000,
+ 1000,
+ 1000,
+ "test",
+ 1,
+ pb.CompressionType_NONE,
+ compression.Level(0),
+ &mockBufferPool{},
+ log.NewLoggerWithLogrus(logrus.StandardLogger()),
+ &mockEncryptor{},
+ )
+ if err != nil {
+ assert.Fail(t, "Failed to create key based batcher")
+ }
+
+ sequenceID := uint64(0)
+ for i := 0; i < 10; i++ {
+ metadata := &pb.SingleMessageMetadata{
+ OrderingKey: []byte(fmt.Sprintf("key-%d", i)),
+ PayloadSize: proto.Int32(0),
+ }
+ assert.True(t, keyBatcher.Add(metadata, &sequenceID, []byte("test"), nil, nil, time.Now(),
+ nil, false, false, 0, 0))
+ }
+
+ batches := keyBatcher.FlushBatches()
+ for i := 1; i < len(batches); i++ {
+ if batches[i].SequenceID <= batches[i-1].SequenceID {
+ t.Errorf("Batch id is not incremental at index %d: %d <= %d", i, batches[i].SequenceID, batches[i-1].SequenceID)
+ }
+ }
+}

pulsar/producer_partition.go

@@ -846,10 +846,11 @@ func (p *partitionProducer) internalFlushCurrentBatch() {
  return
  }
 
- batchData, sequenceID, callbacks, err := p.batchBuilder.Flush()
- if batchData == nil {
+ batch := p.batchBuilder.Flush()
+ if batch == nil {
  return
  }
+ batchData, sequenceID, callbacks, err := batch.BatchData, batch.SequenceID, batch.Callbacks, batch.Error
 
  // error occurred in batch flush
  // report it using callback
@@ -969,38 +970,38 @@ func (p *partitionProducer) failTimeoutMessages() {
 }
 
 func (p *partitionProducer) internalFlushCurrentBatches() {
- batchesData, sequenceIDs, callbacks, errs := p.batchBuilder.FlushBatches()
- if batchesData == nil {
+ flushBatches := p.batchBuilder.FlushBatches()
+ if flushBatches == nil {
  return
  }
 
- for i := range batchesData {
+ for _, b := range flushBatches {
  // error occurred in processing batch
  // report it using callback
- if errs[i] != nil {
- for _, cb := range callbacks[i] {
+ if b.Error != nil {
+ for _, cb := range b.Callbacks {
  if sr, ok := cb.(*sendRequest); ok {
- sr.done(nil, errs[i])
+ sr.done(nil, b.Error)
  }
  }
 
- if errors.Is(errs[i], internal.ErrExceedMaxMessageSize) {
- p.log.WithError(ErrMessageTooLarge).Errorf("internal err: %s", errs[i])
+ if errors.Is(b.Error, internal.ErrExceedMaxMessageSize) {
+ p.log.WithError(ErrMessageTooLarge).Errorf("internal err: %s", b.Error)
  return
  }
 
  continue
  }
- if batchesData[i] == nil {
+ if b.BatchData == nil {
  continue
  }
  p.pendingQueue.Put(&pendingItem{
  sentAt: time.Now(),
- buffer: batchesData[i],
- sequenceID: sequenceIDs[i],
- sendRequests: callbacks[i],
+ buffer: b.BatchData,
+ sequenceID: b.SequenceID,
+ sendRequests: b.Callbacks,
  })
- p._getConn().WriteData(batchesData[i])
+ p._getConn().WriteData(b.BatchData)
  }
 
 }