[VOL-1386] This commit add "dep" as the package management tool
for voltha-go.
Change-Id: I52bc4911dd00a441756ec7c30f46d45091f3f90e
diff --git a/vendor/github.com/Shopify/sarama/consumer_group.go b/vendor/github.com/Shopify/sarama/consumer_group.go
new file mode 100644
index 0000000..bb6a2c2
--- /dev/null
+++ b/vendor/github.com/Shopify/sarama/consumer_group.go
@@ -0,0 +1,774 @@
+package sarama
+
+import (
+ "context"
+ "errors"
+ "fmt"
+ "sort"
+ "sync"
+ "time"
+)
+
+// ErrClosedConsumerGroup is the error returned when a method is called on a consumer group that has been closed.
+var ErrClosedConsumerGroup = errors.New("kafka: tried to use a consumer group that was closed")
+
+// ConsumerGroup is responsible for dividing up processing of topics and partitions
+// over a collection of processes (the members of the consumer group).
+type ConsumerGroup interface {
+ // Consume joins a cluster of consumers for a given list of topics and
+ // starts a blocking ConsumerGroupSession through the ConsumerGroupHandler.
+ //
+ // The life-cycle of a session is represented by the following steps:
+ //
+ // 1. The consumers join the group (as explained in https://kafka.apache.org/documentation/#intro_consumers)
+ // and is assigned their "fair share" of partitions, aka 'claims'.
+ // 2. Before processing starts, the handler's Setup() hook is called to notify the user
+ // of the claims and allow any necessary preparation or alteration of state.
+ // 3. For each of the assigned claims the handler's ConsumeClaim() function is then called
+ // in a separate goroutine which requires it to be thread-safe. Any state must be carefully protected
+ // from concurrent reads/writes.
+ // 4. The session will persist until one of the ConsumeClaim() functions exits. This can be either when the
+ // parent context is cancelled or when a server-side rebalance cycle is initiated.
+ // 5. Once all the ConsumeClaim() loops have exited, the handler's Cleanup() hook is called
+ // to allow the user to perform any final tasks before a rebalance.
+ // 6. Finally, marked offsets are committed one last time before claims are released.
+ //
+ // Please note, that once a rebalance is triggered, sessions must be completed within
+ // Config.Consumer.Group.Rebalance.Timeout. This means that ConsumeClaim() functions must exit
+ // as quickly as possible to allow time for Cleanup() and the final offset commit. If the timeout
+ // is exceeded, the consumer will be removed from the group by Kafka, which will cause offset
+ // commit failures.
+ Consume(ctx context.Context, topics []string, handler ConsumerGroupHandler) error
+
+ // Errors returns a read channel of errors that occurred during the consumer life-cycle.
+ // By default, errors are logged and not returned over this channel.
+ // If you want to implement any custom error handling, set your config's
+ // Consumer.Return.Errors setting to true, and read from this channel.
+ Errors() <-chan error
+
+ // Close stops the ConsumerGroup and detaches any running sessions. It is required to call
+ // this function before the object passes out of scope, as it will otherwise leak memory.
+ Close() error
+}
+
+type consumerGroup struct {
+ client Client
+ ownClient bool
+
+ config *Config
+ consumer Consumer
+ groupID string
+ memberID string
+ errors chan error
+
+ lock sync.Mutex
+ closed chan none
+ closeOnce sync.Once
+}
+
+// NewConsumerGroup creates a new consumer group the given broker addresses and configuration.
+func NewConsumerGroup(addrs []string, groupID string, config *Config) (ConsumerGroup, error) {
+ client, err := NewClient(addrs, config)
+ if err != nil {
+ return nil, err
+ }
+
+ c, err := NewConsumerGroupFromClient(groupID, client)
+ if err != nil {
+ _ = client.Close()
+ return nil, err
+ }
+
+ c.(*consumerGroup).ownClient = true
+ return c, nil
+}
+
+// NewConsumerGroupFromClient creates a new consumer group using the given client. It is still
+// necessary to call Close() on the underlying client when shutting down this consumer.
+// PLEASE NOTE: consumer groups can only re-use but not share clients.
+func NewConsumerGroupFromClient(groupID string, client Client) (ConsumerGroup, error) {
+ config := client.Config()
+ if !config.Version.IsAtLeast(V0_10_2_0) {
+ return nil, ConfigurationError("consumer groups require Version to be >= V0_10_2_0")
+ }
+
+ consumer, err := NewConsumerFromClient(client)
+ if err != nil {
+ return nil, err
+ }
+
+ return &consumerGroup{
+ client: client,
+ consumer: consumer,
+ config: config,
+ groupID: groupID,
+ errors: make(chan error, config.ChannelBufferSize),
+ closed: make(chan none),
+ }, nil
+}
+
+// Errors implements ConsumerGroup.
+func (c *consumerGroup) Errors() <-chan error { return c.errors }
+
+// Close implements ConsumerGroup.
+func (c *consumerGroup) Close() (err error) {
+ c.closeOnce.Do(func() {
+ close(c.closed)
+
+ c.lock.Lock()
+ defer c.lock.Unlock()
+
+ // leave group
+ if e := c.leave(); e != nil {
+ err = e
+ }
+
+ // drain errors
+ go func() {
+ close(c.errors)
+ }()
+ for e := range c.errors {
+ err = e
+ }
+
+ if c.ownClient {
+ if e := c.client.Close(); e != nil {
+ err = e
+ }
+ }
+ })
+ return
+}
+
+// Consume implements ConsumerGroup.
+func (c *consumerGroup) Consume(ctx context.Context, topics []string, handler ConsumerGroupHandler) error {
+ // Ensure group is not closed
+ select {
+ case <-c.closed:
+ return ErrClosedConsumerGroup
+ default:
+ }
+
+ c.lock.Lock()
+ defer c.lock.Unlock()
+
+ // Quick exit when no topics are provided
+ if len(topics) == 0 {
+ return fmt.Errorf("no topics provided")
+ }
+
+ // Refresh metadata for requested topics
+ if err := c.client.RefreshMetadata(topics...); err != nil {
+ return err
+ }
+
+ // Get coordinator
+ coordinator, err := c.client.Coordinator(c.groupID)
+ if err != nil {
+ return err
+ }
+
+ // Init session
+ sess, err := c.newSession(ctx, coordinator, topics, handler, c.config.Consumer.Group.Rebalance.Retry.Max)
+ if err == ErrClosedClient {
+ return ErrClosedConsumerGroup
+ } else if err != nil {
+ return err
+ }
+
+ // Wait for session exit signal
+ <-sess.ctx.Done()
+
+ // Gracefully release session claims
+ return sess.release(true)
+}
+
+func (c *consumerGroup) newSession(ctx context.Context, coordinator *Broker, topics []string, handler ConsumerGroupHandler, retries int) (*consumerGroupSession, error) {
+ // Join consumer group
+ join, err := c.joinGroupRequest(coordinator, topics)
+ if err != nil {
+ _ = coordinator.Close()
+ return nil, err
+ }
+ switch join.Err {
+ case ErrNoError:
+ c.memberID = join.MemberId
+ case ErrUnknownMemberId, ErrIllegalGeneration: // reset member ID and retry immediately
+ c.memberID = ""
+ return c.newSession(ctx, coordinator, topics, handler, retries)
+ case ErrRebalanceInProgress: // retry after backoff
+ if retries <= 0 {
+ return nil, join.Err
+ }
+
+ select {
+ case <-c.closed:
+ return nil, ErrClosedConsumerGroup
+ case <-time.After(c.config.Consumer.Group.Rebalance.Retry.Backoff):
+ }
+
+ return c.newSession(ctx, coordinator, topics, handler, retries-1)
+ default:
+ return nil, join.Err
+ }
+
+ // Prepare distribution plan if we joined as the leader
+ var plan BalanceStrategyPlan
+ if join.LeaderId == join.MemberId {
+ members, err := join.GetMembers()
+ if err != nil {
+ return nil, err
+ }
+
+ plan, err = c.balance(members)
+ if err != nil {
+ return nil, err
+ }
+ }
+
+ // Sync consumer group
+ sync, err := c.syncGroupRequest(coordinator, plan, join.GenerationId)
+ if err != nil {
+ _ = coordinator.Close()
+ return nil, err
+ }
+ switch sync.Err {
+ case ErrNoError:
+ case ErrUnknownMemberId, ErrIllegalGeneration: // reset member ID and retry immediately
+ c.memberID = ""
+ return c.newSession(ctx, coordinator, topics, handler, retries)
+ case ErrRebalanceInProgress: // retry after backoff
+ if retries <= 0 {
+ return nil, sync.Err
+ }
+
+ select {
+ case <-c.closed:
+ return nil, ErrClosedConsumerGroup
+ case <-time.After(c.config.Consumer.Group.Rebalance.Retry.Backoff):
+ }
+
+ return c.newSession(ctx, coordinator, topics, handler, retries-1)
+ default:
+ return nil, sync.Err
+ }
+
+ // Retrieve and sort claims
+ var claims map[string][]int32
+ if len(sync.MemberAssignment) > 0 {
+ members, err := sync.GetMemberAssignment()
+ if err != nil {
+ return nil, err
+ }
+ claims = members.Topics
+
+ for _, partitions := range claims {
+ sort.Sort(int32Slice(partitions))
+ }
+ }
+
+ return newConsumerGroupSession(ctx, c, claims, join.MemberId, join.GenerationId, handler)
+}
+
+func (c *consumerGroup) joinGroupRequest(coordinator *Broker, topics []string) (*JoinGroupResponse, error) {
+ req := &JoinGroupRequest{
+ GroupId: c.groupID,
+ MemberId: c.memberID,
+ SessionTimeout: int32(c.config.Consumer.Group.Session.Timeout / time.Millisecond),
+ ProtocolType: "consumer",
+ }
+ if c.config.Version.IsAtLeast(V0_10_1_0) {
+ req.Version = 1
+ req.RebalanceTimeout = int32(c.config.Consumer.Group.Rebalance.Timeout / time.Millisecond)
+ }
+
+ meta := &ConsumerGroupMemberMetadata{
+ Topics: topics,
+ UserData: c.config.Consumer.Group.Member.UserData,
+ }
+ strategy := c.config.Consumer.Group.Rebalance.Strategy
+ if err := req.AddGroupProtocolMetadata(strategy.Name(), meta); err != nil {
+ return nil, err
+ }
+
+ return coordinator.JoinGroup(req)
+}
+
+func (c *consumerGroup) syncGroupRequest(coordinator *Broker, plan BalanceStrategyPlan, generationID int32) (*SyncGroupResponse, error) {
+ req := &SyncGroupRequest{
+ GroupId: c.groupID,
+ MemberId: c.memberID,
+ GenerationId: generationID,
+ }
+ for memberID, topics := range plan {
+ err := req.AddGroupAssignmentMember(memberID, &ConsumerGroupMemberAssignment{
+ Topics: topics,
+ })
+ if err != nil {
+ return nil, err
+ }
+ }
+ return coordinator.SyncGroup(req)
+}
+
+func (c *consumerGroup) heartbeatRequest(coordinator *Broker, memberID string, generationID int32) (*HeartbeatResponse, error) {
+ req := &HeartbeatRequest{
+ GroupId: c.groupID,
+ MemberId: memberID,
+ GenerationId: generationID,
+ }
+
+ return coordinator.Heartbeat(req)
+}
+
+func (c *consumerGroup) balance(members map[string]ConsumerGroupMemberMetadata) (BalanceStrategyPlan, error) {
+ topics := make(map[string][]int32)
+ for _, meta := range members {
+ for _, topic := range meta.Topics {
+ topics[topic] = nil
+ }
+ }
+
+ for topic := range topics {
+ partitions, err := c.client.Partitions(topic)
+ if err != nil {
+ return nil, err
+ }
+ topics[topic] = partitions
+ }
+
+ strategy := c.config.Consumer.Group.Rebalance.Strategy
+ return strategy.Plan(members, topics)
+}
+
+// Leaves the cluster, called by Close, protected by lock.
+func (c *consumerGroup) leave() error {
+ if c.memberID == "" {
+ return nil
+ }
+
+ coordinator, err := c.client.Coordinator(c.groupID)
+ if err != nil {
+ return err
+ }
+
+ resp, err := coordinator.LeaveGroup(&LeaveGroupRequest{
+ GroupId: c.groupID,
+ MemberId: c.memberID,
+ })
+ if err != nil {
+ _ = coordinator.Close()
+ return err
+ }
+
+ // Unset memberID
+ c.memberID = ""
+
+ // Check response
+ switch resp.Err {
+ case ErrRebalanceInProgress, ErrUnknownMemberId, ErrNoError:
+ return nil
+ default:
+ return resp.Err
+ }
+}
+
+func (c *consumerGroup) handleError(err error, topic string, partition int32) {
+ select {
+ case <-c.closed:
+ return
+ default:
+ }
+
+ if _, ok := err.(*ConsumerError); !ok && topic != "" && partition > -1 {
+ err = &ConsumerError{
+ Topic: topic,
+ Partition: partition,
+ Err: err,
+ }
+ }
+
+ if c.config.Consumer.Return.Errors {
+ select {
+ case c.errors <- err:
+ default:
+ }
+ } else {
+ Logger.Println(err)
+ }
+}
+
+// --------------------------------------------------------------------
+
+// ConsumerGroupSession represents a consumer group member session.
+type ConsumerGroupSession interface {
+ // Claims returns information about the claimed partitions by topic.
+ Claims() map[string][]int32
+
+ // MemberID returns the cluster member ID.
+ MemberID() string
+
+ // GenerationID returns the current generation ID.
+ GenerationID() int32
+
+ // MarkOffset marks the provided offset, alongside a metadata string
+ // that represents the state of the partition consumer at that point in time. The
+ // metadata string can be used by another consumer to restore that state, so it
+ // can resume consumption.
+ //
+ // To follow upstream conventions, you are expected to mark the offset of the
+ // next message to read, not the last message read. Thus, when calling `MarkOffset`
+ // you should typically add one to the offset of the last consumed message.
+ //
+ // Note: calling MarkOffset does not necessarily commit the offset to the backend
+ // store immediately for efficiency reasons, and it may never be committed if
+ // your application crashes. This means that you may end up processing the same
+ // message twice, and your processing should ideally be idempotent.
+ MarkOffset(topic string, partition int32, offset int64, metadata string)
+
+ // ResetOffset resets to the provided offset, alongside a metadata string that
+ // represents the state of the partition consumer at that point in time. Reset
+ // acts as a counterpart to MarkOffset, the difference being that it allows to
+ // reset an offset to an earlier or smaller value, where MarkOffset only
+ // allows incrementing the offset. cf MarkOffset for more details.
+ ResetOffset(topic string, partition int32, offset int64, metadata string)
+
+ // MarkMessage marks a message as consumed.
+ MarkMessage(msg *ConsumerMessage, metadata string)
+
+ // Context returns the session context.
+ Context() context.Context
+}
+
+type consumerGroupSession struct {
+ parent *consumerGroup
+ memberID string
+ generationID int32
+ handler ConsumerGroupHandler
+
+ claims map[string][]int32
+ offsets *offsetManager
+ ctx context.Context
+ cancel func()
+
+ waitGroup sync.WaitGroup
+ releaseOnce sync.Once
+ hbDying, hbDead chan none
+}
+
+func newConsumerGroupSession(ctx context.Context, parent *consumerGroup, claims map[string][]int32, memberID string, generationID int32, handler ConsumerGroupHandler) (*consumerGroupSession, error) {
+ // init offset manager
+ offsets, err := newOffsetManagerFromClient(parent.groupID, memberID, generationID, parent.client)
+ if err != nil {
+ return nil, err
+ }
+
+ // init context
+ ctx, cancel := context.WithCancel(ctx)
+
+ // init session
+ sess := &consumerGroupSession{
+ parent: parent,
+ memberID: memberID,
+ generationID: generationID,
+ handler: handler,
+ offsets: offsets,
+ claims: claims,
+ ctx: ctx,
+ cancel: cancel,
+ hbDying: make(chan none),
+ hbDead: make(chan none),
+ }
+
+ // start heartbeat loop
+ go sess.heartbeatLoop()
+
+ // create a POM for each claim
+ for topic, partitions := range claims {
+ for _, partition := range partitions {
+ pom, err := offsets.ManagePartition(topic, partition)
+ if err != nil {
+ _ = sess.release(false)
+ return nil, err
+ }
+
+ // handle POM errors
+ go func(topic string, partition int32) {
+ for err := range pom.Errors() {
+ sess.parent.handleError(err, topic, partition)
+ }
+ }(topic, partition)
+ }
+ }
+
+ // perform setup
+ if err := handler.Setup(sess); err != nil {
+ _ = sess.release(true)
+ return nil, err
+ }
+
+ // start consuming
+ for topic, partitions := range claims {
+ for _, partition := range partitions {
+ sess.waitGroup.Add(1)
+
+ go func(topic string, partition int32) {
+ defer sess.waitGroup.Done()
+
+ // cancel the as session as soon as the first
+ // goroutine exits
+ defer sess.cancel()
+
+ // consume a single topic/partition, blocking
+ sess.consume(topic, partition)
+ }(topic, partition)
+ }
+ }
+ return sess, nil
+}
+
+func (s *consumerGroupSession) Claims() map[string][]int32 { return s.claims }
+func (s *consumerGroupSession) MemberID() string { return s.memberID }
+func (s *consumerGroupSession) GenerationID() int32 { return s.generationID }
+
+func (s *consumerGroupSession) MarkOffset(topic string, partition int32, offset int64, metadata string) {
+ if pom := s.offsets.findPOM(topic, partition); pom != nil {
+ pom.MarkOffset(offset, metadata)
+ }
+}
+
+func (s *consumerGroupSession) ResetOffset(topic string, partition int32, offset int64, metadata string) {
+ if pom := s.offsets.findPOM(topic, partition); pom != nil {
+ pom.ResetOffset(offset, metadata)
+ }
+}
+
+func (s *consumerGroupSession) MarkMessage(msg *ConsumerMessage, metadata string) {
+ s.MarkOffset(msg.Topic, msg.Partition, msg.Offset+1, metadata)
+}
+
+func (s *consumerGroupSession) Context() context.Context {
+ return s.ctx
+}
+
+func (s *consumerGroupSession) consume(topic string, partition int32) {
+ // quick exit if rebalance is due
+ select {
+ case <-s.ctx.Done():
+ return
+ case <-s.parent.closed:
+ return
+ default:
+ }
+
+ // get next offset
+ offset := s.parent.config.Consumer.Offsets.Initial
+ if pom := s.offsets.findPOM(topic, partition); pom != nil {
+ offset, _ = pom.NextOffset()
+ }
+
+ // create new claim
+ claim, err := newConsumerGroupClaim(s, topic, partition, offset)
+ if err != nil {
+ s.parent.handleError(err, topic, partition)
+ return
+ }
+
+ // handle errors
+ go func() {
+ for err := range claim.Errors() {
+ s.parent.handleError(err, topic, partition)
+ }
+ }()
+
+ // trigger close when session is done
+ go func() {
+ select {
+ case <-s.ctx.Done():
+ case <-s.parent.closed:
+ }
+ claim.AsyncClose()
+ }()
+
+ // start processing
+ if err := s.handler.ConsumeClaim(s, claim); err != nil {
+ s.parent.handleError(err, topic, partition)
+ }
+
+ // ensure consumer is closed & drained
+ claim.AsyncClose()
+ for _, err := range claim.waitClosed() {
+ s.parent.handleError(err, topic, partition)
+ }
+}
+
+func (s *consumerGroupSession) release(withCleanup bool) (err error) {
+ // signal release, stop heartbeat
+ s.cancel()
+
+ // wait for consumers to exit
+ s.waitGroup.Wait()
+
+ // perform release
+ s.releaseOnce.Do(func() {
+ if withCleanup {
+ if e := s.handler.Cleanup(s); e != nil {
+ s.parent.handleError(err, "", -1)
+ err = e
+ }
+ }
+
+ if e := s.offsets.Close(); e != nil {
+ err = e
+ }
+
+ close(s.hbDying)
+ <-s.hbDead
+ })
+
+ return
+}
+
+func (s *consumerGroupSession) heartbeatLoop() {
+ defer close(s.hbDead)
+ defer s.cancel() // trigger the end of the session on exit
+
+ pause := time.NewTicker(s.parent.config.Consumer.Group.Heartbeat.Interval)
+ defer pause.Stop()
+
+ retries := s.parent.config.Metadata.Retry.Max
+ for {
+ coordinator, err := s.parent.client.Coordinator(s.parent.groupID)
+ if err != nil {
+ if retries <= 0 {
+ s.parent.handleError(err, "", -1)
+ return
+ }
+
+ select {
+ case <-s.hbDying:
+ return
+ case <-time.After(s.parent.config.Metadata.Retry.Backoff):
+ retries--
+ }
+ continue
+ }
+
+ resp, err := s.parent.heartbeatRequest(coordinator, s.memberID, s.generationID)
+ if err != nil {
+ _ = coordinator.Close()
+ retries--
+ continue
+ }
+
+ switch resp.Err {
+ case ErrNoError:
+ retries = s.parent.config.Metadata.Retry.Max
+ case ErrRebalanceInProgress, ErrUnknownMemberId, ErrIllegalGeneration:
+ return
+ default:
+ s.parent.handleError(err, "", -1)
+ return
+ }
+
+ select {
+ case <-pause.C:
+ case <-s.hbDying:
+ return
+ }
+ }
+}
+
+// --------------------------------------------------------------------
+
+// ConsumerGroupHandler instances are used to handle individual topic/partition claims.
+// It also provides hooks for your consumer group session life-cycle and allow you to
+// trigger logic before or after the consume loop(s).
+//
+// PLEASE NOTE that handlers are likely be called from several goroutines concurrently,
+// ensure that all state is safely protected against race conditions.
+type ConsumerGroupHandler interface {
+ // Setup is run at the beginning of a new session, before ConsumeClaim.
+ Setup(ConsumerGroupSession) error
+
+ // Cleanup is run at the end of a session, once all ConsumeClaim goroutines have exited
+ // but before the offsets are committed for the very last time.
+ Cleanup(ConsumerGroupSession) error
+
+ // ConsumeClaim must start a consumer loop of ConsumerGroupClaim's Messages().
+ // Once the Messages() channel is closed, the Handler must finish its processing
+ // loop and exit.
+ ConsumeClaim(ConsumerGroupSession, ConsumerGroupClaim) error
+}
+
+// ConsumerGroupClaim processes Kafka messages from a given topic and partition within a consumer group.
+type ConsumerGroupClaim interface {
+ // Topic returns the consumed topic name.
+ Topic() string
+
+ // Partition returns the consumed partition.
+ Partition() int32
+
+ // InitialOffset returns the initial offset that was used as a starting point for this claim.
+ InitialOffset() int64
+
+ // HighWaterMarkOffset returns the high water mark offset of the partition,
+ // i.e. the offset that will be used for the next message that will be produced.
+ // You can use this to determine how far behind the processing is.
+ HighWaterMarkOffset() int64
+
+ // Messages returns the read channel for the messages that are returned by
+ // the broker. The messages channel will be closed when a new rebalance cycle
+ // is due. You must finish processing and mark offsets within
+ // Config.Consumer.Group.Session.Timeout before the topic/partition is eventually
+ // re-assigned to another group member.
+ Messages() <-chan *ConsumerMessage
+}
+
+type consumerGroupClaim struct {
+ topic string
+ partition int32
+ offset int64
+ PartitionConsumer
+}
+
+func newConsumerGroupClaim(sess *consumerGroupSession, topic string, partition int32, offset int64) (*consumerGroupClaim, error) {
+ pcm, err := sess.parent.consumer.ConsumePartition(topic, partition, offset)
+ if err == ErrOffsetOutOfRange {
+ offset = sess.parent.config.Consumer.Offsets.Initial
+ pcm, err = sess.parent.consumer.ConsumePartition(topic, partition, offset)
+ }
+ if err != nil {
+ return nil, err
+ }
+
+ go func() {
+ for err := range pcm.Errors() {
+ sess.parent.handleError(err, topic, partition)
+ }
+ }()
+
+ return &consumerGroupClaim{
+ topic: topic,
+ partition: partition,
+ offset: offset,
+ PartitionConsumer: pcm,
+ }, nil
+}
+
+func (c *consumerGroupClaim) Topic() string { return c.topic }
+func (c *consumerGroupClaim) Partition() int32 { return c.partition }
+func (c *consumerGroupClaim) InitialOffset() int64 { return c.offset }
+
+// Drains messages and errors, ensures the claim is fully closed.
+func (c *consumerGroupClaim) waitClosed() (errs ConsumerErrors) {
+ go func() {
+ for range c.Messages() {
+ }
+ }()
+
+ for err := range c.Errors() {
+ errs = append(errs, err)
+ }
+ return
+}