restic/vendor/cloud.google.com/go/pubsub/example_test.go

270 lines
6.6 KiB
Go

// Copyright 2014 Google Inc. All Rights Reserved.
//
// 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_test
import (
"fmt"
"time"
"cloud.google.com/go/pubsub"
"golang.org/x/net/context"
"google.golang.org/api/iterator"
)
func ExampleNewClient() {
ctx := context.Background()
_, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
// TODO: Handle error.
}
// See the other examples to learn how to use the Client.
}
func ExampleClient_CreateTopic() {
ctx := context.Background()
client, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
// TODO: Handle error.
}
// Create a new topic with the given name.
topic, err := client.CreateTopic(ctx, "topicName")
if err != nil {
// TODO: Handle error.
}
_ = topic // TODO: use the topic.
}
func ExampleClient_CreateSubscription() {
ctx := context.Background()
client, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
// TODO: Handle error.
}
// Create a new topic with the given name.
topic, err := client.CreateTopic(ctx, "topicName")
if err != nil {
// TODO: Handle error.
}
// Create a new subscription to the previously created topic
// with the given name.
sub, err := client.CreateSubscription(ctx, "subName", pubsub.SubscriptionConfig{
Topic: topic,
AckDeadline: 10 * time.Second,
})
if err != nil {
// TODO: Handle error.
}
_ = sub // TODO: use the subscription.
}
func ExampleTopic_Delete() {
ctx := context.Background()
client, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
// TODO: Handle error.
}
topic := client.Topic("topicName")
if err := topic.Delete(ctx); err != nil {
// TODO: Handle error.
}
}
func ExampleTopic_Exists() {
ctx := context.Background()
client, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
// TODO: Handle error.
}
topic := client.Topic("topicName")
ok, err := topic.Exists(ctx)
if err != nil {
// TODO: Handle error.
}
if !ok {
// Topic doesn't exist.
}
}
func ExampleTopic_Publish() {
ctx := context.Background()
client, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
// TODO: Handle error.
}
topic := client.Topic("topicName")
defer topic.Stop()
var results []*pubsub.PublishResult
r := topic.Publish(ctx, &pubsub.Message{
Data: []byte("hello world"),
})
results = append(results, r)
// Do other work ...
for _, r := range results {
id, err := r.Get(ctx)
if err != nil {
// TODO: Handle error.
}
fmt.Printf("Published a message with a message ID: %s\n", id)
}
}
func ExampleTopic_Subscriptions() {
ctx := context.Background()
client, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
// TODO: Handle error.
}
topic := client.Topic("topic-name")
// List all subscriptions of the topic (maybe of multiple projects).
for subs := topic.Subscriptions(ctx); ; {
sub, err := subs.Next()
if err == iterator.Done {
break
}
if err != nil {
// TODO: Handle error.
}
_ = sub // TODO: use the subscription.
}
}
func ExampleSubscription_Delete() {
ctx := context.Background()
client, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
// TODO: Handle error.
}
sub := client.Subscription("subName")
if err := sub.Delete(ctx); err != nil {
// TODO: Handle error.
}
}
func ExampleSubscription_Exists() {
ctx := context.Background()
client, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
// TODO: Handle error.
}
sub := client.Subscription("subName")
ok, err := sub.Exists(ctx)
if err != nil {
// TODO: Handle error.
}
if !ok {
// Subscription doesn't exist.
}
}
func ExampleSubscription_Config() {
ctx := context.Background()
client, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
// TODO: Handle error.
}
sub := client.Subscription("subName")
config, err := sub.Config(ctx)
if err != nil {
// TODO: Handle error.
}
fmt.Println(config)
}
func ExampleSubscription_Receive() {
ctx := context.Background()
client, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
// TODO: Handle error.
}
sub := client.Subscription("subName")
err = sub.Receive(ctx, func(ctx context.Context, m *pubsub.Message) {
// TODO: Handle message.
// NOTE: May be called concurrently; synchronize access to shared memory.
m.Ack()
})
if err != context.Canceled {
// TODO: Handle error.
}
}
// This example shows how to configure keepalive so that unacknoweldged messages
// expire quickly, allowing other subscribers to take them.
func ExampleSubscription_Receive_maxExtension() {
ctx := context.Background()
client, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
// TODO: Handle error.
}
sub := client.Subscription("subName")
// This program is expected to process and acknowledge messages in 30 seconds. If
// not, the Pub/Sub API will assume the message is not acknowledged.
sub.ReceiveSettings.MaxExtension = 30 * time.Second
err = sub.Receive(ctx, func(ctx context.Context, m *pubsub.Message) {
// TODO: Handle message.
m.Ack()
})
if err != context.Canceled {
// TODO: Handle error.
}
}
// This example shows how to throttle Subscription.Receive, which aims for high
// throughput by default. By limiting the number of messages and/or bytes being
// processed at once, you can bound your program's resource consumption.
func ExampleSubscription_Receive_maxOutstanding() {
ctx := context.Background()
client, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
// TODO: Handle error.
}
sub := client.Subscription("subName")
sub.ReceiveSettings.MaxOutstandingMessages = 5
sub.ReceiveSettings.MaxOutstandingBytes = 10e6
err = sub.Receive(ctx, func(ctx context.Context, m *pubsub.Message) {
// TODO: Handle message.
m.Ack()
})
if err != context.Canceled {
// TODO: Handle error.
}
}
func ExampleSubscription_Update() {
ctx := context.Background()
client, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
// TODO: Handle error.
}
sub := client.Subscription("subName")
subConfig, err := sub.Update(ctx, pubsub.SubscriptionConfigToUpdate{
PushConfig: &pubsub.PushConfig{Endpoint: "https://example.com/push"},
})
if err != nil {
// TODO: Handle error.
}
_ = subConfig // TODO: Use SubscriptionConfig.
}