/
publish_scale.go
71 lines (61 loc) · 1.84 KB
/
publish_scale.go
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// Copyright 2019 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
//
// https://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 topics
// [START pubsub_publish_with_error_handler]
import (
"context"
"fmt"
"io"
"strconv"
"sync"
"sync/atomic"
"cloud.google.com/go/pubsub"
)
func publishThatScales(w io.Writer, projectID, topicID string, n int) error {
// projectID := "my-project-id"
// topicID := "my-topic"
ctx := context.Background()
client, err := pubsub.NewClient(ctx, projectID)
if err != nil {
return fmt.Errorf("pubsub.NewClient: %v", err)
}
var wg sync.WaitGroup
var totalErrors uint64
t := client.Topic(topicID)
for i := 0; i < n; i++ {
result := t.Publish(ctx, &pubsub.Message{
Data: []byte("Message " + strconv.Itoa(i)),
})
wg.Add(1)
go func(i int, res *pubsub.PublishResult) {
defer wg.Done()
// The Get method blocks until a server-generated ID or
// an error is returned for the published message.
id, err := res.Get(ctx)
if err != nil {
// Error handling code can be added here.
fmt.Fprintf(w, "Failed to publish: %v", err)
atomic.AddUint64(&totalErrors, 1)
return
}
fmt.Fprintf(w, "Published message %d; msg ID: %v\n", i, id)
}(i, result)
}
wg.Wait()
if totalErrors > 0 {
return fmt.Errorf("%d of %d messages did not publish successfully", totalErrors, n)
}
return nil
}
// [END pubsub_publish_with_error_handler]