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topic.go
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topic.go
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// Copyright 2016 Google LLC
//
// Licensed 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 pubsub
import (
"context"
"errors"
"fmt"
"log"
"runtime"
"strings"
"sync"
"time"
"cloud.google.com/go/iam"
"cloud.google.com/go/internal/optional"
ipubsub "cloud.google.com/go/internal/pubsub"
vkit "cloud.google.com/go/pubsub/apiv1"
pb "cloud.google.com/go/pubsub/apiv1/pubsubpb"
"cloud.google.com/go/pubsub/internal/scheduler"
gax "github.com/googleapis/gax-go/v2"
"go.opencensus.io/stats"
"go.opencensus.io/tag"
"google.golang.org/api/support/bundler"
"google.golang.org/grpc"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/status"
"google.golang.org/protobuf/proto"
"google.golang.org/protobuf/types/known/durationpb"
fmpb "google.golang.org/protobuf/types/known/fieldmaskpb"
)
const (
// MaxPublishRequestCount is the maximum number of messages that can be in
// a single publish request, as defined by the PubSub service.
MaxPublishRequestCount = 1000
// MaxPublishRequestBytes is the maximum size of a single publish request
// in bytes, as defined by the PubSub service.
MaxPublishRequestBytes = 1e7
)
const (
// TODO: math.MaxInt was added in Go 1.17. We should use that once 1.17
// becomes the minimum supported version of Go.
intSize = 32 << (^uint(0) >> 63)
maxInt = 1<<(intSize-1) - 1
)
// ErrOversizedMessage indicates that a message's size exceeds MaxPublishRequestBytes.
var ErrOversizedMessage = bundler.ErrOversizedItem
// Topic is a reference to a PubSub topic.
//
// The methods of Topic are safe for use by multiple goroutines.
type Topic struct {
c *Client
// The fully qualified identifier for the topic, in the format "projects/<projid>/topics/<name>"
name string
// Settings for publishing messages. All changes must be made before the
// first call to Publish. The default is DefaultPublishSettings.
PublishSettings PublishSettings
mu sync.RWMutex
stopped bool
scheduler *scheduler.PublishScheduler
flowController
// EnableMessageOrdering enables delivery of ordered keys.
EnableMessageOrdering bool
}
// PublishSettings control the bundling of published messages.
type PublishSettings struct {
// Publish a non-empty batch after this delay has passed.
DelayThreshold time.Duration
// Publish a batch when it has this many messages. The maximum is
// MaxPublishRequestCount.
CountThreshold int
// Publish a batch when its size in bytes reaches this value.
ByteThreshold int
// The number of goroutines used in each of the data structures that are
// involved along the the Publish path. Adjusting this value adjusts
// concurrency along the publish path.
//
// Defaults to a multiple of GOMAXPROCS.
NumGoroutines int
// The maximum time that the client will attempt to publish a bundle of messages.
Timeout time.Duration
// The maximum number of bytes that the Bundler will keep in memory before
// returning ErrOverflow. This is now superseded by FlowControlSettings.MaxOutstandingBytes.
// If MaxOutstandingBytes is set, that value will override BufferedByteLimit.
//
// Defaults to DefaultPublishSettings.BufferedByteLimit.
// Deprecated: Set `Topic.PublishSettings.FlowControlSettings.MaxOutstandingBytes` instead.
BufferedByteLimit int
// FlowControlSettings defines publisher flow control settings.
FlowControlSettings FlowControlSettings
}
// DefaultPublishSettings holds the default values for topics' PublishSettings.
var DefaultPublishSettings = PublishSettings{
DelayThreshold: 10 * time.Millisecond,
CountThreshold: 100,
ByteThreshold: 1e6,
Timeout: 60 * time.Second,
// By default, limit the bundler to 10 times the max message size. The number 10 is
// chosen as a reasonable amount of messages in the worst case whilst still
// capping the number to a low enough value to not OOM users.
BufferedByteLimit: 10 * MaxPublishRequestBytes,
FlowControlSettings: FlowControlSettings{
MaxOutstandingMessages: 1000,
MaxOutstandingBytes: -1,
LimitExceededBehavior: FlowControlIgnore,
},
}
// CreateTopic creates a new topic.
//
// The specified topic ID must start with a letter, and contain only letters
// ([A-Za-z]), numbers ([0-9]), dashes (-), underscores (_), periods (.),
// tildes (~), plus (+) or percent signs (%). It must be between 3 and 255
// characters in length, and must not start with "goog". For more information,
// see: https://cloud.google.com/pubsub/docs/admin#resource_names
//
// If the topic already exists an error will be returned.
func (c *Client) CreateTopic(ctx context.Context, topicID string) (*Topic, error) {
t := c.Topic(topicID)
_, err := c.pubc.CreateTopic(ctx, &pb.Topic{Name: t.name})
if err != nil {
return nil, err
}
return t, nil
}
// CreateTopicWithConfig creates a topic from TopicConfig.
//
// The specified topic ID must start with a letter, and contain only letters
// ([A-Za-z]), numbers ([0-9]), dashes (-), underscores (_), periods (.),
// tildes (~), plus (+) or percent signs (%). It must be between 3 and 255
// characters in length, and must not start with "goog". For more information,
// see: https://cloud.google.com/pubsub/docs/admin#resource_names.
//
// If the topic already exists, an error will be returned.
func (c *Client) CreateTopicWithConfig(ctx context.Context, topicID string, tc *TopicConfig) (*Topic, error) {
t := c.Topic(topicID)
topic := tc.toProto()
topic.Name = t.name
_, err := c.pubc.CreateTopic(ctx, topic)
if err != nil {
return nil, err
}
return t, nil
}
// Topic creates a reference to a topic in the client's project.
//
// If a Topic's Publish method is called, it has background goroutines
// associated with it. Clean them up by calling Topic.Stop.
//
// Avoid creating many Topic instances if you use them to publish.
func (c *Client) Topic(id string) *Topic {
return c.TopicInProject(id, c.projectID)
}
// TopicInProject creates a reference to a topic in the given project.
//
// If a Topic's Publish method is called, it has background goroutines
// associated with it. Clean them up by calling Topic.Stop.
//
// Avoid creating many Topic instances if you use them to publish.
func (c *Client) TopicInProject(id, projectID string) *Topic {
return newTopic(c, fmt.Sprintf("projects/%s/topics/%s", projectID, id))
}
func newTopic(c *Client, name string) *Topic {
return &Topic{
c: c,
name: name,
PublishSettings: DefaultPublishSettings,
}
}
// TopicConfig describes the configuration of a topic.
type TopicConfig struct {
// The fully qualified identifier for the topic, in the format "projects/<projid>/topics/<name>"
name string
// The set of labels for the topic.
Labels map[string]string
// The topic's message storage policy.
MessageStoragePolicy MessageStoragePolicy
// The name of the Cloud KMS key to be used to protect access to messages
// published to this topic, in the format
// "projects/P/locations/L/keyRings/R/cryptoKeys/K".
KMSKeyName string
// Schema defines the schema settings upon topic creation.
SchemaSettings *SchemaSettings
// RetentionDuration configures the minimum duration to retain a message
// after it is published to the topic. If this field is set, messages published
// to the topic in the last `RetentionDuration` are always available to subscribers.
// For instance, it allows any attached subscription to [seek to a
// timestamp](https://cloud.google.com/pubsub/docs/replay-overview#seek_to_a_time)
// that is up to `RetentionDuration` in the past. If this field is
// not set, message retention is controlled by settings on individual
// subscriptions. Cannot be more than 31 days or less than 10 minutes.
//
// For more information, see https://cloud.google.com/pubsub/docs/replay-overview#topic_message_retention.
RetentionDuration optional.Duration
}
// String returns the printable globally unique name for the topic config.
// This method only works when the topic config is returned from the server,
// such as when calling `client.Topic` or `client.Topics`.
// Otherwise, this will return an empty string.
func (t *TopicConfig) String() string {
return t.name
}
// ID returns the unique identifier of the topic within its project.
// This method only works when the topic config is returned from the server,
// such as when calling `client.Topic` or `client.Topics`.
// Otherwise, this will return an empty string.
func (t *TopicConfig) ID() string {
slash := strings.LastIndex(t.name, "/")
if slash == -1 {
return ""
}
return t.name[slash+1:]
}
func (tc *TopicConfig) toProto() *pb.Topic {
var retDur *durationpb.Duration
if tc.RetentionDuration != nil {
retDur = durationpb.New(optional.ToDuration(tc.RetentionDuration))
}
pbt := &pb.Topic{
Labels: tc.Labels,
MessageStoragePolicy: messageStoragePolicyToProto(&tc.MessageStoragePolicy),
KmsKeyName: tc.KMSKeyName,
SchemaSettings: schemaSettingsToProto(tc.SchemaSettings),
MessageRetentionDuration: retDur,
}
return pbt
}
// TopicConfigToUpdate describes how to update a topic.
type TopicConfigToUpdate struct {
// If non-nil, the current set of labels is completely
// replaced by the new set.
Labels map[string]string
// If non-nil, the existing policy (containing the list of regions)
// is completely replaced by the new policy.
//
// Use the zero value &MessageStoragePolicy{} to reset the topic back to
// using the organization's Resource Location Restriction policy.
//
// If nil, the policy remains unchanged.
//
// This field has beta status. It is not subject to the stability guarantee
// and may change.
MessageStoragePolicy *MessageStoragePolicy
// If set to a positive duration between 10 minutes and 31 days, RetentionDuration is changed.
// If set to a negative value, this clears RetentionDuration from the topic.
// If nil, the retention duration remains unchanged.
RetentionDuration optional.Duration
// Schema defines the schema settings upon topic creation.
//
// Use the zero value &SchemaSettings{} to remove the schema from the topic.
SchemaSettings *SchemaSettings
}
func protoToTopicConfig(pbt *pb.Topic) TopicConfig {
tc := TopicConfig{
name: pbt.Name,
Labels: pbt.Labels,
MessageStoragePolicy: protoToMessageStoragePolicy(pbt.MessageStoragePolicy),
KMSKeyName: pbt.KmsKeyName,
SchemaSettings: protoToSchemaSettings(pbt.SchemaSettings),
}
if pbt.GetMessageRetentionDuration() != nil {
tc.RetentionDuration = pbt.GetMessageRetentionDuration().AsDuration()
}
return tc
}
// DetachSubscriptionResult is the response for the DetachSubscription method.
// Reserved for future use.
type DetachSubscriptionResult struct{}
// DetachSubscription detaches a subscription from its topic. All messages
// retained in the subscription are dropped. Subsequent `Pull` and `StreamingPull`
// requests will return FAILED_PRECONDITION. If the subscription is a push
// subscription, pushes to the endpoint will stop.
func (c *Client) DetachSubscription(ctx context.Context, sub string) (*DetachSubscriptionResult, error) {
_, err := c.pubc.DetachSubscription(ctx, &pb.DetachSubscriptionRequest{
Subscription: sub,
})
if err != nil {
return nil, err
}
return &DetachSubscriptionResult{}, nil
}
// MessageStoragePolicy constrains how messages published to the topic may be stored. It
// is determined when the topic is created based on the policy configured at
// the project level.
type MessageStoragePolicy struct {
// AllowedPersistenceRegions is the list of GCP regions where messages that are published
// to the topic may be persisted in storage. Messages published by publishers running in
// non-allowed GCP regions (or running outside of GCP altogether) will be
// routed for storage in one of the allowed regions.
//
// If empty, it indicates a misconfiguration at the project or organization level, which
// will result in all Publish operations failing. This field cannot be empty in updates.
//
// If nil, then the policy is not defined on a topic level. When used in updates, it resets
// the regions back to the organization level Resource Location Restriction policy.
//
// For more information, see
// https://cloud.google.com/pubsub/docs/resource-location-restriction#pubsub-storage-locations.
AllowedPersistenceRegions []string
}
func protoToMessageStoragePolicy(msp *pb.MessageStoragePolicy) MessageStoragePolicy {
if msp == nil {
return MessageStoragePolicy{}
}
return MessageStoragePolicy{AllowedPersistenceRegions: msp.AllowedPersistenceRegions}
}
func messageStoragePolicyToProto(msp *MessageStoragePolicy) *pb.MessageStoragePolicy {
if msp == nil || msp.AllowedPersistenceRegions == nil {
return nil
}
return &pb.MessageStoragePolicy{AllowedPersistenceRegions: msp.AllowedPersistenceRegions}
}
// Config returns the TopicConfig for the topic.
func (t *Topic) Config(ctx context.Context) (TopicConfig, error) {
pbt, err := t.c.pubc.GetTopic(ctx, &pb.GetTopicRequest{Topic: t.name})
if err != nil {
return TopicConfig{}, err
}
return protoToTopicConfig(pbt), nil
}
// Update changes an existing topic according to the fields set in cfg. It returns
// the new TopicConfig.
func (t *Topic) Update(ctx context.Context, cfg TopicConfigToUpdate) (TopicConfig, error) {
req := t.updateRequest(cfg)
if len(req.UpdateMask.Paths) == 0 {
return TopicConfig{}, errors.New("pubsub: UpdateTopic call with nothing to update")
}
rpt, err := t.c.pubc.UpdateTopic(ctx, req)
if err != nil {
return TopicConfig{}, err
}
return protoToTopicConfig(rpt), nil
}
func (t *Topic) updateRequest(cfg TopicConfigToUpdate) *pb.UpdateTopicRequest {
pt := &pb.Topic{Name: t.name}
var paths []string
if cfg.Labels != nil {
pt.Labels = cfg.Labels
paths = append(paths, "labels")
}
if cfg.MessageStoragePolicy != nil {
pt.MessageStoragePolicy = messageStoragePolicyToProto(cfg.MessageStoragePolicy)
paths = append(paths, "message_storage_policy")
}
if cfg.RetentionDuration != nil {
r := optional.ToDuration(cfg.RetentionDuration)
pt.MessageRetentionDuration = durationpb.New(r)
if r < 0 {
// Clear MessageRetentionDuration if sentinel value is read.
pt.MessageRetentionDuration = nil
}
paths = append(paths, "message_retention_duration")
}
// Updating SchemaSettings' field masks are more complicated here
// since each field should be able to be independently edited, while
// preserving the current values for everything else. We also denote
// the zero value SchemaSetting to mean clearing or removing schema
// from the topic.
if cfg.SchemaSettings != nil {
pt.SchemaSettings = schemaSettingsToProto(cfg.SchemaSettings)
clearSchema := true
if pt.SchemaSettings.Schema != "" {
paths = append(paths, "schema_settings.schema")
clearSchema = false
}
if pt.SchemaSettings.Encoding != pb.Encoding_ENCODING_UNSPECIFIED {
paths = append(paths, "schema_settings.encoding")
clearSchema = false
}
if pt.SchemaSettings.FirstRevisionId != "" {
paths = append(paths, "schema_settings.first_revision_id")
clearSchema = false
}
if pt.SchemaSettings.LastRevisionId != "" {
paths = append(paths, "schema_settings.last_revision_id")
clearSchema = false
}
// Clear the schema if all of its values are equal to the zero value.
if clearSchema {
paths = append(paths, "schema_settings")
pt.SchemaSettings = nil
}
}
return &pb.UpdateTopicRequest{
Topic: pt,
UpdateMask: &fmpb.FieldMask{Paths: paths},
}
}
// Topics returns an iterator which returns all of the topics for the client's project.
func (c *Client) Topics(ctx context.Context) *TopicIterator {
it := c.pubc.ListTopics(ctx, &pb.ListTopicsRequest{Project: c.fullyQualifiedProjectName()})
return &TopicIterator{
c: c,
it: it,
next: func() (string, error) {
topic, err := it.Next()
if err != nil {
return "", err
}
return topic.Name, nil
},
}
}
// TopicIterator is an iterator that returns a series of topics.
type TopicIterator struct {
c *Client
it *vkit.TopicIterator
next func() (string, error)
}
// Next returns the next topic. If there are no more topics, iterator.Done will be returned.
func (tps *TopicIterator) Next() (*Topic, error) {
topicName, err := tps.next()
if err != nil {
return nil, err
}
return newTopic(tps.c, topicName), nil
}
// NextConfig returns the next topic config. If there are no more topics,
// iterator.Done will be returned.
// This call shares the underlying iterator with calls to `TopicIterator.Next`.
// If you wish to use mix calls, create separate iterator instances for both.
func (t *TopicIterator) NextConfig() (*TopicConfig, error) {
tpb, err := t.it.Next()
if err != nil {
return nil, err
}
cfg := protoToTopicConfig(tpb)
return &cfg, nil
}
// ID returns the unique identifier of the topic within its project.
func (t *Topic) ID() string {
slash := strings.LastIndex(t.name, "/")
if slash == -1 {
// name is not a fully-qualified name.
panic("bad topic name")
}
return t.name[slash+1:]
}
// String returns the printable globally unique name for the topic.
func (t *Topic) String() string {
return t.name
}
// Delete deletes the topic.
func (t *Topic) Delete(ctx context.Context) error {
return t.c.pubc.DeleteTopic(ctx, &pb.DeleteTopicRequest{Topic: t.name})
}
// Exists reports whether the topic exists on the server.
func (t *Topic) Exists(ctx context.Context) (bool, error) {
if t.name == "_deleted-topic_" {
return false, nil
}
_, err := t.c.pubc.GetTopic(ctx, &pb.GetTopicRequest{Topic: t.name})
if err == nil {
return true, nil
}
if status.Code(err) == codes.NotFound {
return false, nil
}
return false, err
}
// IAM returns the topic's IAM handle.
func (t *Topic) IAM() *iam.Handle {
return iam.InternalNewHandle(t.c.pubc.Connection(), t.name)
}
// Subscriptions returns an iterator which returns the subscriptions for this topic.
//
// Some of the returned subscriptions may belong to a project other than t.
func (t *Topic) Subscriptions(ctx context.Context) *SubscriptionIterator {
it := t.c.pubc.ListTopicSubscriptions(ctx, &pb.ListTopicSubscriptionsRequest{
Topic: t.name,
})
return &SubscriptionIterator{
c: t.c,
next: it.Next,
}
}
// ErrTopicStopped indicates that topic has been stopped and further publishing will fail.
var ErrTopicStopped = errors.New("pubsub: Stop has been called for this topic")
// A PublishResult holds the result from a call to Publish.
//
// Call Get to obtain the result of the Publish call. Example:
//
// // Get blocks until Publish completes or ctx is done.
// id, err := r.Get(ctx)
// if err != nil {
// // TODO: Handle error.
// }
type PublishResult = ipubsub.PublishResult
var errTopicOrderingNotEnabled = errors.New("Topic.EnableMessageOrdering=false, but an OrderingKey was set in Message. Please remove the OrderingKey or turn on Topic.EnableMessageOrdering")
// Publish publishes msg to the topic asynchronously. Messages are batched and
// sent according to the topic's PublishSettings. Publish never blocks.
//
// Publish returns a non-nil PublishResult which will be ready when the
// message has been sent (or has failed to be sent) to the server.
//
// Publish creates goroutines for batching and sending messages. These goroutines
// need to be stopped by calling t.Stop(). Once stopped, future calls to Publish
// will immediately return a PublishResult with an error.
func (t *Topic) Publish(ctx context.Context, msg *Message) *PublishResult {
ctx, err := tag.New(ctx, tag.Insert(keyStatus, "OK"), tag.Upsert(keyTopic, t.name))
if err != nil {
log.Printf("pubsub: cannot create context with tag in Publish: %v", err)
}
r := ipubsub.NewPublishResult()
if !t.EnableMessageOrdering && msg.OrderingKey != "" {
ipubsub.SetPublishResult(r, "", errTopicOrderingNotEnabled)
return r
}
// Calculate the size of the encoded proto message by accounting
// for the length of an individual PubSubMessage and Data/Attributes field.
msgSize := proto.Size(&pb.PubsubMessage{
Data: msg.Data,
Attributes: msg.Attributes,
OrderingKey: msg.OrderingKey,
})
t.initBundler()
t.mu.RLock()
defer t.mu.RUnlock()
if t.stopped {
ipubsub.SetPublishResult(r, "", ErrTopicStopped)
return r
}
if err := t.flowController.acquire(ctx, msgSize); err != nil {
t.scheduler.Pause(msg.OrderingKey)
ipubsub.SetPublishResult(r, "", err)
return r
}
err = t.scheduler.Add(msg.OrderingKey, &bundledMessage{msg, r, msgSize}, msgSize)
if err != nil {
t.scheduler.Pause(msg.OrderingKey)
ipubsub.SetPublishResult(r, "", err)
}
return r
}
// Stop sends all remaining published messages and stop goroutines created for handling
// publishing. Returns once all outstanding messages have been sent or have
// failed to be sent.
func (t *Topic) Stop() {
t.mu.Lock()
noop := t.stopped || t.scheduler == nil
t.stopped = true
t.mu.Unlock()
if noop {
return
}
t.scheduler.FlushAndStop()
}
// Flush blocks until all remaining messages are sent.
func (t *Topic) Flush() {
if t.stopped || t.scheduler == nil {
return
}
t.scheduler.Flush()
}
type bundledMessage struct {
msg *Message
res *PublishResult
size int
}
func (t *Topic) initBundler() {
t.mu.RLock()
noop := t.stopped || t.scheduler != nil
t.mu.RUnlock()
if noop {
return
}
t.mu.Lock()
defer t.mu.Unlock()
// Must re-check, since we released the lock.
if t.stopped || t.scheduler != nil {
return
}
timeout := t.PublishSettings.Timeout
workers := t.PublishSettings.NumGoroutines
// Unless overridden, allow many goroutines per CPU to call the Publish RPC
// concurrently. The default value was determined via extensive load
// testing (see the loadtest subdirectory).
if t.PublishSettings.NumGoroutines == 0 {
workers = 25 * runtime.GOMAXPROCS(0)
}
t.scheduler = scheduler.NewPublishScheduler(workers, func(bundle interface{}) {
// TODO(jba): use a context detached from the one passed to NewClient.
ctx := context.TODO()
if timeout != 0 {
var cancel func()
ctx, cancel = context.WithTimeout(ctx, timeout)
defer cancel()
}
t.publishMessageBundle(ctx, bundle.([]*bundledMessage))
})
t.scheduler.DelayThreshold = t.PublishSettings.DelayThreshold
t.scheduler.BundleCountThreshold = t.PublishSettings.CountThreshold
if t.scheduler.BundleCountThreshold > MaxPublishRequestCount {
t.scheduler.BundleCountThreshold = MaxPublishRequestCount
}
t.scheduler.BundleByteThreshold = t.PublishSettings.ByteThreshold
fcs := DefaultPublishSettings.FlowControlSettings
fcs.LimitExceededBehavior = t.PublishSettings.FlowControlSettings.LimitExceededBehavior
if t.PublishSettings.FlowControlSettings.MaxOutstandingBytes > 0 {
b := t.PublishSettings.FlowControlSettings.MaxOutstandingBytes
fcs.MaxOutstandingBytes = b
// If MaxOutstandingBytes is set, disable BufferedByteLimit by setting it to maxint.
// This is because there's no way to set "unlimited" for BufferedByteLimit,
// and simply setting it to MaxOutstandingBytes occasionally leads to issues where
// BufferedByteLimit is reached even though there are resources available.
t.PublishSettings.BufferedByteLimit = maxInt
}
if t.PublishSettings.FlowControlSettings.MaxOutstandingMessages > 0 {
fcs.MaxOutstandingMessages = t.PublishSettings.FlowControlSettings.MaxOutstandingMessages
}
t.flowController = newTopicFlowController(fcs)
bufferedByteLimit := DefaultPublishSettings.BufferedByteLimit
if t.PublishSettings.BufferedByteLimit > 0 {
bufferedByteLimit = t.PublishSettings.BufferedByteLimit
}
t.scheduler.BufferedByteLimit = bufferedByteLimit
// Calculate the max limit of a single bundle. 5 comes from the number of bytes
// needed to be reserved for encoding the PubsubMessage repeated field.
t.scheduler.BundleByteLimit = MaxPublishRequestBytes - calcFieldSizeString(t.name) - 5
}
// ErrPublishingPaused is a custom error indicating that the publish paused for the specified ordering key.
type ErrPublishingPaused struct {
OrderingKey string
}
func (e ErrPublishingPaused) Error() string {
return fmt.Sprintf("pubsub: Publishing for ordering key, %s, paused due to previous error. Call topic.ResumePublish(orderingKey) before resuming publishing", e.OrderingKey)
}
func (t *Topic) publishMessageBundle(ctx context.Context, bms []*bundledMessage) {
ctx, err := tag.New(ctx, tag.Insert(keyStatus, "OK"), tag.Upsert(keyTopic, t.name))
if err != nil {
log.Printf("pubsub: cannot create context with tag in publishMessageBundle: %v", err)
}
pbMsgs := make([]*pb.PubsubMessage, len(bms))
var orderingKey string
for i, bm := range bms {
orderingKey = bm.msg.OrderingKey
pbMsgs[i] = &pb.PubsubMessage{
Data: bm.msg.Data,
Attributes: bm.msg.Attributes,
OrderingKey: bm.msg.OrderingKey,
}
bm.msg = nil // release bm.msg for GC
}
var res *pb.PublishResponse
start := time.Now()
if orderingKey != "" && t.scheduler.IsPaused(orderingKey) {
err = ErrPublishingPaused{OrderingKey: orderingKey}
} else {
// Apply custom publish retryer on top of user specified retryer and
// default retryer.
opts := t.c.pubc.CallOptions.Publish
var settings gax.CallSettings
for _, opt := range opts {
opt.Resolve(&settings)
}
r := &publishRetryer{defaultRetryer: settings.Retry()}
res, err = t.c.pubc.Publish(ctx, &pb.PublishRequest{
Topic: t.name,
Messages: pbMsgs,
}, gax.WithGRPCOptions(grpc.MaxCallSendMsgSize(maxSendRecvBytes)),
gax.WithRetry(func() gax.Retryer { return r }))
}
end := time.Now()
if err != nil {
t.scheduler.Pause(orderingKey)
// Update context with error tag for OpenCensus,
// using same stats.Record() call as success case.
ctx, _ = tag.New(ctx, tag.Upsert(keyStatus, "ERROR"),
tag.Upsert(keyError, err.Error()))
}
stats.Record(ctx,
PublishLatency.M(float64(end.Sub(start)/time.Millisecond)),
PublishedMessages.M(int64(len(bms))))
for i, bm := range bms {
t.flowController.release(ctx, bm.size)
if err != nil {
ipubsub.SetPublishResult(bm.res, "", err)
} else {
ipubsub.SetPublishResult(bm.res, res.MessageIds[i], nil)
}
}
}
// ResumePublish resumes accepting messages for the provided ordering key.
// Publishing using an ordering key might be paused if an error is
// encountered while publishing, to prevent messages from being published
// out of order.
func (t *Topic) ResumePublish(orderingKey string) {
t.mu.RLock()
noop := t.scheduler == nil
t.mu.RUnlock()
if noop {
return
}
t.scheduler.Resume(orderingKey)
}