Publisher Guide

PublisherServiceApiClient publisherClient = PublisherServiceApiClient.Create();
PublisherClient publisher = PublisherClient.Create(
    new TopicName(projectId, topicId), new[] { publisherClient });

t := client.Topic(topic)
result := t.Publish(ctx, &pubsub.Message{
	Data: []byte(msg),
})
// Block until the result is returned and a server-generated
// ID is returned for the published message.
id, err := result.Get(ctx)
if err != nil {
	return err
}
fmt.Printf("Published a message; msg ID: %v\n", id)

ProjectTopicName topicName = ProjectTopicName.of("my-project-id", "my-topic-id");
Publisher publisher = null;

try {
  // Create a publisher instance with default settings bound to the topic
  publisher = Publisher.newBuilder(topicName).build();

  List<String> messages = Arrays.asList("first message", "second message");

  for (final String message : messages) {
    ByteString data = ByteString.copyFromUtf8(message);
    PubsubMessage pubsubMessage = PubsubMessage.newBuilder().setData(data).build();

    // Once published, returns a server-assigned message id (unique within the topic)
    ApiFuture<String> future = publisher.publish(pubsubMessage);

    // Add an asynchronous callback to handle success / failure
    ApiFutures.addCallback(future, new ApiFutureCallback<String>() {

      @Override
      public void onFailure(Throwable throwable) {
        if (throwable instanceof ApiException) {
          ApiException apiException = ((ApiException) throwable);
          // details on the API exception
          System.out.println(apiException.getStatusCode().getCode());
          System.out.println(apiException.isRetryable());
        }
        System.out.println("Error publishing message : " + message);
      }

      @Override
      public void onSuccess(String messageId) {
        // Once published, returns server-assigned message ids (unique within the topic)
        System.out.println(messageId);
      }
    });
  }
} finally {
  if (publisher != null) {
    // When finished with the publisher, shutdown to free up resources.
    publisher.shutdown();
  }
}

// Imports the Google Cloud client library
const PubSub = require(`@google-cloud/pubsub`);

// Creates a client
const pubsub = new PubSub();

/**
 * TODO(developer): Uncomment the following lines to run the sample.
 */
// const topicName = 'your-topic';
// const data = JSON.stringify({ foo: 'bar' });

// Publishes the message as a string, e.g. "Hello, world!" or JSON.stringify(someObject)
const dataBuffer = Buffer.from(data);

pubsub
  .topic(topicName)
  .publisher()
  .publish(dataBuffer)
  .then(messageId => {
    console.log(`Message ${messageId} published.`);
  })
  .catch(err => {
    console.error('ERROR:', err);
  });

use Google\Cloud\PubSub\PubSubClient;

/**
 * Publishes a message for a Pub/Sub topic.
 *
 * @param string $projectId  The Google project ID.
 * @param string $topicName  The Pub/Sub topic name.
 * @param string $message  The message to publish.
 */
function publish_message($projectId, $topicName, $message)
{
    $pubsub = new PubSubClient([
        'projectId' => $projectId,
    ]);
    $topic = $pubsub->topic($topicName);
    $topic->publish(['data' => $message]);
    print('Message published' . PHP_EOL);
}

publisher = pubsub_v1.PublisherClient()
topic_path = publisher.topic_path(project, topic_name)

def callback(message_future):
    if message_future.exception():
        print('Publishing message on {} threw an Exception {}.'.format(
            topic_name, message_future.exception()))
    else:
        print(message_future.result())

for n in range(1, 10):
    data = u'Message number {}'.format(n)
    # Data must be a bytestring
    data = data.encode('utf-8')
    # When you publish a message, the client returns a Future.
    message_future = publisher.publish(topic_path, data=data)
    message_future.add_done_callback(callback)

print('Published message IDs:')

# We must keep the main thread from exiting to allow it to process
# messages in the background.
while True:
    time.sleep(60)

# project_id = "Your Google Cloud Project ID"
# topic_name = "Your Pubsub topic name"
require "google/cloud/pubsub"

pubsub = Google::Cloud::Pubsub.new project: project_id

topic = pubsub.topic topic_name
topic.publish_async "This is a test message." do |result|
  if result.succeeded?
    puts "Message published asynchronously."
  else
    raise "Failed to publish the message."
  end
end

# Stop the async_publisher to send all queued messages immediately.
topic.async_publisher.stop.wait!

// Imports the Google Cloud client library
const PubSub = require(`@google-cloud/pubsub`);

// Creates a client
const pubsub = new PubSub();

/**
 * TODO(developer): Uncomment the following lines to run the sample.
 */
// const topicName = 'your-topic';
// const data = JSON.stringify({ foo: 'bar' });

// Publishes the message as a string, e.g. "Hello, world!" or JSON.stringify(someObject)
const dataBuffer = Buffer.from(data);
// Add two custom attributes, origin and username, to the message
const customAttributes = {
  origin: 'nodejs-sample',
  username: 'gcp',
};

pubsub
  .topic(topicName)
  .publisher()
  .publish(dataBuffer, customAttributes)
  .then(messageId => {
    console.log(`Message ${messageId} published.`);
  })
  .catch(err => {
    console.error('ERROR:', err);
  });

publisher = pubsub_v1.PublisherClient()
topic_path = publisher.topic_path(project, topic_name)

for n in range(1, 10):
    data = u'Message number {}'.format(n)
    # Data must be a bytestring
    data = data.encode('utf-8')
    # Add two attributes, origin and username, to the message
    publisher.publish(
        topic_path, data, origin='python-sample', username='gcp')

print('Published messages with custom attributes.')

# project_id = "Your Google Cloud Project ID"
# topic_name = "Your Pubsub topic name"
require "google/cloud/pubsub"

pubsub = Google::Cloud::Pubsub.new project: project_id

topic = pubsub.topic topic_name
# Add two attributes, origin and username, to the message
topic.publish_async "This is a test message.",
                    origin: "ruby-sample",
                    username: "gcp" do |result|
  if result.succeeded?
    puts "Message with custom attributes published asynchronously."
  else
    raise "Failed to publish the message."
  end
end

# Stop the async_publisher to send all queued messages immediately.
topic.async_publisher.stop.wait!

PublisherServiceApiClient publisherClient = PublisherServiceApiClient.Create();
PublisherClient publisher = PublisherClient.Create(
    new TopicName(projectId, topicId), new[] { publisherClient },
    new PublisherClient.Settings
    {
        BatchingSettings = new Google.Api.Gax.BatchingSettings(
            elementCountThreshold: 100,
            byteCountThreshold: 10240,
            delayThreshold: TimeSpan.FromSeconds(3))
    });
var publishTasks = new List<Task<string>>();
// SimplePublisher collects messages into appropriately sized
// batches.
foreach (string text in messageTexts)
{
    publishTasks.Add(publisher.PublishAsync(text));
}
foreach (var task in publishTasks)
{
    Console.WriteLine("Published message {0}", task.Result);
}

t := client.Topic(topic)
t.PublishSettings = pubsub.PublishSettings{
	ByteThreshold:  5000,
	CountThreshold: 10,
	DelayThreshold: 100 * time.Millisecond,
}
result := t.Publish(ctx, &pubsub.Message{Data: msg})
// Block until the result is returned and a server-generated
// ID is returned for the published message.
id, err := result.Get(ctx)
if err != nil {
	return err
}
fmt.Printf("Published a message; msg ID: %v\n", id)

// Batch settings control how the publisher batches messages
long requestBytesThreshold = 5000L; // default : 1kb
long messageCountBatchSize = 10L; // default : 100

Duration publishDelayThreshold = Duration.ofMillis(100); // default : 1 ms

// Publish request get triggered based on request size, messages count & time since last publish
BatchingSettings batchingSettings = BatchingSettings.newBuilder()
    .setElementCountThreshold(messageCountBatchSize)
    .setRequestByteThreshold(requestBytesThreshold)
    .setDelayThreshold(publishDelayThreshold)
    .build();

Publisher publisher = Publisher.newBuilder(topicName)
    .setBatchingSettings(batchingSettings).build();

// Imports the Google Cloud client library
const PubSub = require(`@google-cloud/pubsub`);

// Creates a client
const pubsub = new PubSub();

/**
 * TODO(developer): Uncomment the following lines to run the sample.
 */
// const topicName = 'your-topic';
// const data = JSON.stringify({ foo: 'bar' });
// const maxMessages = 10;
// const maxWaitTime = 10000;

// Publishes the message as a string, e.g. "Hello, world!" or JSON.stringify(someObject)
const dataBuffer = Buffer.from(data);

pubsub
  .topic(topicName)
  .publisher({
    batching: {
      maxMessages: maxMessages,
      maxMilliseconds: maxWaitTime,
    },
  })
  .publish(dataBuffer)
  .then(results => {
    const messageId = results[0];
    console.log(`Message ${messageId} published.`);
  })
  .catch(err => {
    console.error('ERROR:', err);
  });

# Configure the batch to publish once there is one kilobyte of data or
# 1 second has passed.
batch_settings = pubsub_v1.types.BatchSettings(
    max_bytes=1024,  # One kilobyte
    max_latency=1,  # One second
)
publisher = pubsub_v1.PublisherClient(batch_settings)
topic_path = publisher.topic_path(project, topic_name)

for n in range(1, 10):
    data = u'Message number {}'.format(n)
    # Data must be a bytestring
    data = data.encode('utf-8')
    publisher.publish(topic_path, data=data)

print('Published messages.')

# project_id = "Your Google Cloud Project ID"
# topic_name = "Your Pubsub topic name"
require "google/cloud/pubsub"

pubsub = Google::Cloud::Pubsub.new project: project_id

topic = pubsub.topic topic_name
topic.publish do |batch|
  10.times do |i|
    batch.publish "This is message \##{i}."
  end
end

puts "Messages published in batch."
# project_id = "Your Google Cloud Project ID"
# topic_name = "Your Pubsub topic name"
require "google/cloud/pubsub"

pubsub = Google::Cloud::Pubsub.new project: project_id

# Start sending messages in one request once the size of all queued messages
# reaches 1 MB or the number of queued messages reaches 20
topic = pubsub.topic topic_name, async: {
  :max_bytes => 1000000,
  :max_messages => 20
}
10.times do |i|
  topic.publish_async "This is message \##{i}."
end

# Stop the async_publisher to send all queued messages immediately.
topic.async_publisher.stop.wait!
puts "Messages published asynchronously in batch."

// Retry settings control how the publisher handles retryable failures
Duration retryDelay = Duration.ofMillis(100); // default : 1 ms
double retryDelayMultiplier = 2.0; // back off for repeated failures
Duration maxRetryDelay = Duration.ofSeconds(5); // default : 10 seconds

RetrySettings retrySettings = RetrySettings.newBuilder()
    .setInitialRetryDelay(retryDelay)
    .setRetryDelayMultiplier(retryDelayMultiplier)
    .setMaxRetryDelay(maxRetryDelay)
    .build();

Publisher publisher = Publisher.newBuilder(topicName)
    .setRetrySettings(retrySettings).build();

t := client.Topic(topic)
t.PublishSettings = pubsub.PublishSettings{
	NumGoroutines: 1,
}
result := t.Publish(ctx, &pubsub.Message{Data: msg})
// Block until the result is returned and a server-generated
// ID is returned for the published message.
id, err := result.Get(ctx)
if err != nil {
	return err
}
fmt.Printf("Published a message; msg ID: %v\n", id)

// create a publisher with a single threaded executor
ExecutorProvider executorProvider = InstantiatingExecutorProvider.newBuilder()
    .setExecutorThreadCount(1).build();
Publisher publisher = Publisher.newBuilder(topicName)
    .setExecutorProvider(executorProvider).build();

publisher = pubsub_v1.PublisherClient()
topic_path = publisher.topic_path(project, topic_name)

# When you publish a message, the client returns a Future. This Future
# can be used to track when the message is published.
futures = []

for n in range(1, 10):
    data = u'Message number {}'.format(n)
    # Data must be a bytestring
    data = data.encode('utf-8')
    message_future = publisher.publish(topic_path, data=data)
    futures.append(message_future)

print('Published message IDs:')
for future in futures:
    # result() blocks until the message is published.
    print(future.result())

# project_id = "Your Google Cloud Project ID"
# topic_name = "Your Pubsub topic name"
require "google/cloud/pubsub"

pubsub = Google::Cloud::Pubsub.new project: project_id

topic = pubsub.topic topic_name, async: {
  :threads => {
    # Use exactly one thread for publishing message and exactly one thread
    # for executing callbacks
    :publish => 1,
    :callback => 1
  }
}
topic.publish_async "This is a test message." do |result|
  if result.succeeded?
    puts "Message published asynchronously."
  else
    raise "Failed to publish the message."
  end
end

# Stop the async_publisher to send all queued messages immediately.
topic.async_publisher.stop.wait!