[feat][txn]Implement transactional consumer/producer API

pulsar/client.go

@@ -184,6 +184,17 @@ type Client interface {
 	// {@link Consumer} or {@link Producer} instances directly on a particular partition.
 	TopicPartitions(topic string) ([]string, error)
 
+	// NewTransaction creates a new Transaction instance.
+	//
+	// This function is used to initiate a new transaction for performing
+	// atomic operations on the message broker. It returns a Transaction
+	// object that can be used to produce, consume and commit messages in a
+	// transactional manner.
+	//
+	// In case of any errors while creating the transaction, an error will
+	// be returned.
+	NewTransaction(duration time.Duration) (Transaction, error)
+
 	// Close Closes the Client and free associated resources
 	Close()
 }

pulsar/client_impl.go

@@ -195,6 +195,11 @@ func newClient(options ClientOptions) (Client, error) {
 	return c, nil
 }
 
+func (c *client) NewTransaction(timeout time.Duration) (Transaction, error) {
+	id, err := c.tcClient.newTransaction(timeout)
+	return newTransaction(*id, c.tcClient, timeout), err
+}
+
 func (c *client) CreateProducer(options ProducerOptions) (Producer, error) {
 	producer, err := newProducer(c, &options)
 	if err == nil {

pulsar/consumer.go

@@ -265,6 +265,9 @@ type Consumer interface {
 	// AckID the consumption of a single message, identified by its MessageID
 	AckID(MessageID) error
 
+	// AckWithTxn the consumption of a single message with a transaction
+	AckWithTxn(Message, Transaction) error
+
 	// AckCumulative the reception of all the messages in the stream up to (and including)
 	// the provided message.
 	AckCumulative(msg Message) error

pulsar/consumer_impl.go

@@ -38,6 +38,7 @@ type acker interface {
 	// AckID does not handle errors returned by the Broker side, so no need to wait for doneCh to finish.
 	AckID(id MessageID) error
 	AckIDWithResponse(id MessageID) error
+	AckIDWithTxn(msgID MessageID, txn Transaction) error
 	AckIDCumulative(msgID MessageID) error
 	AckIDWithResponseCumulative(msgID MessageID) error
 	NackID(id MessageID)
@@ -478,6 +479,15 @@ func (c *consumer) Receive(ctx context.Context) (message Message, err error) {
 	}
 }
 
+func (c *consumer) AckWithTxn(msg Message, txn Transaction) error {
+	msgID := msg.ID()
+	if err := c.checkMsgIDPartition(msgID); err != nil {
+		return err
+	}
+
+	return c.consumers[msgID.PartitionIdx()].AckIDWithTxn(msgID, txn)
+}
+
 // Chan return the message chan to users
 func (c *consumer) Chan() <-chan ConsumerMessage {
 	return c.messageCh

pulsar/consumer_multitopic.go

@@ -143,6 +143,23 @@ func (c *multiTopicConsumer) AckID(msgID MessageID) error {
 	return mid.consumer.AckID(msgID)
 }
 
+// AckWithTxn the consumption of a single message with a transaction
+func (c *multiTopicConsumer) AckWithTxn(msg Message, txn Transaction) error {
+	msgID := msg.ID()
+	if !checkMessageIDType(msgID) {
+		c.log.Warnf("invalid message id type %T", msgID)
+		return errors.New("invalid message id type in multi_consumer")
+	}
+	mid := toTrackingMessageID(msgID)
+
+	if mid.consumer == nil {
+		c.log.Warnf("unable to ack messageID=%+v can not determine topic", msgID)
+		return errors.New("unable to ack message because consumer is nil")
+	}
+
+	return mid.consumer.AckIDWithTxn(msgID, txn)
+}
+
 // AckCumulative the reception of all the messages in the stream up to (and including)
 // the provided message
 func (c *multiTopicConsumer) AckCumulative(msg Message) error {

pulsar/consumer_partition.go

@@ -417,6 +417,93 @@ func (pc *partitionConsumer) Unsubscribe() error {
 	return req.err
 }
 
+func (pc *partitionConsumer) AckIDWithTxn(msgID MessageID, txn Transaction) error {
+	if state := pc.getConsumerState(); state == consumerClosed || state == consumerClosing {
+		pc.log.WithField("state", state).Error("Failed to ack by closing or closed consumer")
+		return errors.New("consumer state is closed")
+	}
+
+	if cmid, ok := msgID.(*chunkMessageID); ok {
+		return pc.unAckChunksTracker.ack(cmid)
+	}
+
+	trackingID := toTrackingMessageID(msgID)
+
+	if trackingID != nil && trackingID.ack() {
+		// All messages in the same batch have been acknowledged, we only need to acknowledge the
+		// MessageID that represents the entry that stores the whole batch
+		trackingID = &trackingMessageID{
+			messageID: &messageID{
+				ledgerID: trackingID.ledgerID,
+				entryID:  trackingID.entryID,
+			},
+		}
+		pc.metrics.AcksCounter.Inc()
+		pc.metrics.ProcessingTime.Observe(float64(time.Now().UnixNano()-trackingID.receivedTime.UnixNano()) / 1.0e9)
+	} else if !pc.options.enableBatchIndexAck {
+		return nil
+	}
+
+	ackReq := pc.sendIndividualAckWithTxn(trackingID, txn.(*transaction))
+	<-ackReq.doneCh
+	pc.options.interceptors.OnAcknowledge(pc.parentConsumer, msgID)
+	if ackReq == nil {
+		return nil
+	}
+	return ackReq.err
+}
+
+func (pc *partitionConsumer) internalAckWithTxn(req *ackWithTxnRequest) {
+	defer close(req.doneCh)
+	if state := pc.getConsumerState(); state == consumerClosed || state == consumerClosing {
+		pc.log.WithField("state", state).Error("Failed to ack by closing or closed consumer")
+		req.err = newError(ConsumerClosed, "Failed to ack by closing or closed consumer")
+		return
+	}
+	msgID := req.msgID
+
+	messageIDs := make([]*pb.MessageIdData, 1)
+	messageIDs[0] = &pb.MessageIdData{
+		LedgerId: proto.Uint64(uint64(msgID.ledgerID)),
+		EntryId:  proto.Uint64(uint64(msgID.entryID)),
+	}
+	if pc.options.enableBatchIndexAck && msgID.tracker != nil {
+		ackSet := msgID.tracker.toAckSet()
+		if ackSet != nil {
+			messageIDs[0].AckSet = ackSet
+		}
+	}
+
+	reqID := pc.client.rpcClient.NewRequestID()
+	txnID := req.Transaction.GetTxnID()
+	cmdAck := &pb.CommandAck{
+		ConsumerId:     proto.Uint64(pc.consumerID),
+		MessageId:      messageIDs,
+		AckType:        pb.CommandAck_Individual.Enum(),
+		TxnidMostBits:  proto.Uint64(txnID.MostSigBits),
+		TxnidLeastBits: proto.Uint64(txnID.LeastSigBits),
+	}
+
+	err := req.Transaction.registerAckTopic(pc.options.topic, pc.options.subscription)
+	if err != nil {
+		req.err = err
+		return
+	}
+	err = req.Transaction.registerSendOrAckOp()
+	if err != nil {
+		req.err = err
+		return
+	}
+	cmdAck.RequestId = proto.Uint64(reqID)
+	_, err = pc.client.rpcClient.RequestOnCnx(pc._getConn(), reqID, pb.BaseCommand_ACK, cmdAck)
+	if err != nil {
+		pc.log.WithError(err).Error("Ack with response error")
+		req.err = err
+	}
+	req.Transaction.endSendOrAckOp(err)
+	req.err = err
+}
+
 func (pc *partitionConsumer) internalUnsubscribe(unsub *unsubscribeRequest) {
 	defer close(unsub.doneCh)
 
@@ -539,6 +626,17 @@ func (pc *partitionConsumer) sendIndividualAck(msgID MessageID) *ackRequest {
 	return ackReq
 }
 
+func (pc *partitionConsumer) sendIndividualAckWithTxn(msgID MessageID, txn *transaction) *ackWithTxnRequest {
+	ackReq := &ackWithTxnRequest{
+		Transaction: txn,
+		doneCh:      make(chan struct{}),
+		ackType:     individualAck,
+		msgID:       *msgID.(*trackingMessageID),
+	}
+	pc.eventsCh <- ackReq
+	return ackReq
+}
+
 func (pc *partitionConsumer) AckIDWithResponse(msgID MessageID) error {
 	if !checkMessageIDType(msgID) {
 		pc.log.Errorf("invalid message id type %T", msgID)
@@ -1389,6 +1487,14 @@ type ackRequest struct {
 	err     error
 }
 
+type ackWithTxnRequest struct {
+	doneCh      chan struct{}
+	msgID       trackingMessageID
+	Transaction *transaction
+	ackType     int
+	err         error
+}
+
 type unsubscribeRequest struct {
 	doneCh chan struct{}
 	err    error
@@ -1444,6 +1550,8 @@ func (pc *partitionConsumer) runEventsLoop() {
 			switch v := i.(type) {
 			case *ackRequest:
 				pc.internalAck(v)
+			case *ackWithTxnRequest:
+				pc.internalAckWithTxn(v)
 			case []*pb.MessageIdData:
 				pc.internalAckList(v)
 			case *redeliveryRequest:

pulsar/consumer_regex.go

@@ -193,6 +193,24 @@ func (c *regexConsumer) AckID(msgID MessageID) error {
 	return mid.consumer.AckID(msgID)
 }
 
+// AckID the consumption of a single message, identified by its MessageID
+func (c *regexConsumer) AckWithTxn(msg Message, txn Transaction) error {
+	msgID := msg.ID()
+	if !checkMessageIDType(msgID) {
+		c.log.Warnf("invalid message id type %T", msgID)
+		return fmt.Errorf("invalid message id type %T", msgID)
+	}
+
+	mid := toTrackingMessageID(msgID)
+
+	if mid.consumer == nil {
+		c.log.Warnf("unable to ack messageID=%+v can not determine topic", msgID)
+		return errors.New("consumer is nil in consumer_regex")
+	}
+
+	return mid.consumer.AckIDWithTxn(msgID, txn)
+}
+
 // AckCumulative the reception of all the messages in the stream up to (and including)
 // the provided message.
 func (c *regexConsumer) AckCumulative(msg Message) error {

pulsar/helper_for_test.go

@@ -159,7 +159,7 @@ func topicStats(topic string) (map[string]interface{}, error) {
 
 func transactionStats(id *TxnID) (map[string]interface{}, error) {
 	var metadata map[string]interface{}
-	path := fmt.Sprintf("admin/v3/transactions/transactionMetadata/%d/%d", id.mostSigBits, id.leastSigBits)
+	path := fmt.Sprintf("admin/v3/transactions/transactionMetadata/%d/%d", id.MostSigBits, id.LeastSigBits)
 	err := httpGet(path, &metadata)
 	return metadata, err
 }

pulsar/internal/batch_builder.go

@@ -51,6 +51,9 @@ type BatchBuilder interface {
 		payload []byte,
 		callback interface{}, replicateTo []string, deliverAt time.Time,
 		schemaVersion []byte, multiSchemaEnabled bool,
+		useTxn bool,
+		mostSigBits uint64,
+		leastSigBits uint64,
 	) bool
 
 	// Flush all the messages buffered in the client and wait until all messages have been successfully persisted.
@@ -185,6 +188,7 @@ func (bc *batchContainer) Add(
 	payload []byte,
 	callback interface{}, replicateTo []string, deliverAt time.Time,
 	schemaVersion []byte, multiSchemaEnabled bool,
+	useTxn bool, mostSigBits uint64, leastSigBits uint64,
 ) bool {
 
 	if replicateTo != nil && bc.numMessages != 0 {
@@ -223,6 +227,10 @@ func (bc *batchContainer) Add(
 		}
 
 		bc.cmdSend.Send.SequenceId = proto.Uint64(sequenceID)
+		if useTxn {
+			bc.cmdSend.Send.TxnidMostBits = proto.Uint64(mostSigBits)
+			bc.cmdSend.Send.TxnidLeastBits = proto.Uint64(leastSigBits)
+		}
 	}
 	addSingleMessageToBatch(bc.buffer, metadata, payload)
 

pulsar/internal/commands.go

@@ -22,11 +22,10 @@ import (
 	"errors"
 	"fmt"
 
-	"google.golang.org/protobuf/proto"
-
 	"github.com/apache/pulsar-client-go/pulsar/internal/compression"
 	"github.com/apache/pulsar-client-go/pulsar/internal/crypto"
 	pb "github.com/apache/pulsar-client-go/pulsar/internal/pulsar_proto"
+	"google.golang.org/protobuf/proto"
 )
 
 const (
@@ -332,7 +331,10 @@ func SingleSend(wb Buffer,
 	msgMetadata *pb.MessageMetadata,
 	compressedPayload Buffer,
 	encryptor crypto.Encryptor,
-	maxMassageSize uint32) error {
+	maxMassageSize uint32,
+	useTxn bool,
+	mostSigBits uint64,
+	leastSigBits uint64) error {
 	cmdSend := baseCommand(
 		pb.BaseCommand_SEND,
 		&pb.CommandSend{
@@ -344,6 +346,10 @@ func SingleSend(wb Buffer,
 		isChunk := true
 		cmdSend.Send.IsChunk = &isChunk
 	}
+	if useTxn {
+		cmdSend.Send.TxnidMostBits = proto.Uint64(mostSigBits)
+		cmdSend.Send.TxnidLeastBits = proto.Uint64(leastSigBits)
+	}
 	// payload has been compressed so compressionProvider can be nil
 	return serializeMessage(wb, cmdSend, msgMetadata, compressedPayload,
 		nil, encryptor, maxMassageSize, false)

pulsar/internal/http_client.go

@@ -190,10 +190,10 @@ func (c *httpClient) GetWithOptions(endpoint string, obj interface{}, params map
 	}
 
 	resp, err := checkSuccessful(c.doRequest(req))
+	defer safeRespClose(resp)
 	if err != nil {
 		return nil, err
 	}
-	defer safeRespClose(resp)
 
 	if obj != nil {
 		if err := decodeJSONBody(resp, &obj); err != nil {

pulsar/internal/key_based_batch_builder.go

@@ -132,6 +132,9 @@ func (bc *keyBasedBatchContainer) Add(
 	payload []byte,
 	callback interface{}, replicateTo []string, deliverAt time.Time,
 	schemaVersion []byte, multiSchemaEnabled bool,
+	useTxn bool,
+	mostSigBits uint64,
+	leastSigBits uint64,
 ) bool {
 	if replicateTo != nil && bc.numMessages != 0 {
 		// If the current batch is not empty and we're trying to set the replication clusters,
@@ -162,7 +165,7 @@ func (bc *keyBasedBatchContainer) Add(
 	add := batchPart.Add(
 		metadata, sequenceIDGenerator, payload, callback, replicateTo,
 		deliverAt,
-		schemaVersion, multiSchemaEnabled,
+		schemaVersion, multiSchemaEnabled, useTxn, mostSigBits, leastSigBits,
 	)
 	if !add {
 		return false

pulsar/internal/pulsartracing/consumer_interceptor_test.go

@@ -52,6 +52,10 @@ func (c *mockConsumer) Subscription() string {
 	return ""
 }
 
+func (c *mockConsumer) AckWithTxn(msg pulsar.Message, txn pulsar.Transaction) error {
+	return nil
+}
+
 func (c *mockConsumer) Unsubscribe() error {
 	return nil
 }

pulsar/message.go

@@ -69,6 +69,10 @@ type ProducerMessage struct {
 	//Schema assign to the current message
 	//Note: messages may have a different schema from producer schema, use it instead of producer schema when assigned
 	Schema Schema
+
+	//Transaction assign to the current message
+	//Note: The message is not visible before the transaction is committed.
+	Transaction Transaction
 }
 
 // Message abstraction used in Pulsar