Nachrichten in Pub/Sub mit einer Clientbibliothek veröffentlichen und empfangen

Mit dem Pub/Sub-Dienst können Anwendungen Nachrichten verlässlich, schnell und asynchron austauschen. Die Ereignisabfolge ist wie folgt:

  1. Ein Datenersteller veröffentlicht eine Nachricht zu einem Pub/Sub-Thema.
  2. Ein Abonnentenclient erstellt ein Abo für dieses Thema und ruft Nachrichten aus dem Abo ab.

Sie können eine Pub/Sub-Umgebung mit einer der folgenden Methoden einrichten: Google Cloud Console, Cloud Shell, Clientbibliotheken oder REST APIs. Auf dieser Seite erfahren Sie, wie Sie Nachrichten mit Pub/Sub mithilfe von Clientbibliotheken veröffentlichen.

Pub/Sub bietet eine automatisch generierte Clientbibliothek auf hoher und niedriger Ebene. Standardmäßig empfehlen wir, wie in dieser Kurzanleitung, die Clientbibliothek auf hoher Ebene.


Eine detaillierte Anleitung dazu finden Sie direkt in der Google Cloud Console. Klicken Sie dazu einfach auf Anleitung:

Anleitung


Hinweise

  1. Sign in to your Google Cloud account. If you're new to Google Cloud, create an account to evaluate how our products perform in real-world scenarios. New customers also get $300 in free credits to run, test, and deploy workloads.
  2. Install the Google Cloud CLI.

  3. Wenn Sie einen externen Identitätsanbieter (IdP) verwenden, müssen Sie sich zuerst mit Ihrer föderierten Identität in der gcloud CLI anmelden.

  4. Führen Sie folgenden Befehl aus, um die gcloud CLI zu initialisieren:

    gcloud init
  5. Create or select a Google Cloud project.

    • Create a Google Cloud project:

      gcloud projects create PROJECT_ID

      Replace PROJECT_ID with a name for the Google Cloud project you are creating.

    • Select the Google Cloud project that you created:

      gcloud config set project PROJECT_ID

      Replace PROJECT_ID with your Google Cloud project name.

  6. Make sure that billing is enabled for your Google Cloud project.

  7. Enable the Pub/Sub API:

    gcloud services enable pubsub.googleapis.com
  8. Create local authentication credentials for your user account:

    gcloud auth application-default login

    If an authentication error is returned, and you are using an external identity provider (IdP), confirm that you have signed in to the gcloud CLI with your federated identity.

  9. Grant roles to your user account. Run the following command once for each of the following IAM roles: roles/pubsub.admin

    gcloud projects add-iam-policy-binding PROJECT_ID --member="user:USER_IDENTIFIER" --role=ROLE
    • Replace PROJECT_ID with your project ID.
    • Replace USER_IDENTIFIER with the identifier for your user account. For example, user:[email protected].

    • Replace ROLE with each individual role.
  10. Install the Google Cloud CLI.

  11. Wenn Sie einen externen Identitätsanbieter (IdP) verwenden, müssen Sie sich zuerst mit Ihrer föderierten Identität in der gcloud CLI anmelden.

  12. Führen Sie folgenden Befehl aus, um die gcloud CLI zu initialisieren:

    gcloud init
  13. Create or select a Google Cloud project.

    • Create a Google Cloud project:

      gcloud projects create PROJECT_ID

      Replace PROJECT_ID with a name for the Google Cloud project you are creating.

    • Select the Google Cloud project that you created:

      gcloud config set project PROJECT_ID

      Replace PROJECT_ID with your Google Cloud project name.

  14. Make sure that billing is enabled for your Google Cloud project.

  15. Enable the Pub/Sub API:

    gcloud services enable pubsub.googleapis.com
  16. Create local authentication credentials for your user account:

    gcloud auth application-default login

    If an authentication error is returned, and you are using an external identity provider (IdP), confirm that you have signed in to the gcloud CLI with your federated identity.

  17. Grant roles to your user account. Run the following command once for each of the following IAM roles: roles/pubsub.admin

    gcloud projects add-iam-policy-binding PROJECT_ID --member="user:USER_IDENTIFIER" --role=ROLE
    • Replace PROJECT_ID with your project ID.
    • Replace USER_IDENTIFIER with the identifier for your user account. For example, user:[email protected].

    • Replace ROLE with each individual role.
  18. Clientbibliotheken installieren

    Die folgenden Beispiele zeigen, wie Sie die Clientbibliotheken installieren:

    Python

    Weitere Informationen zur Einrichtung der Python-Entwicklungsumgebung finden Sie im Einrichtungshandbuch für die Python-Entwicklungsumgebung.

    # ensure that you are using virtualenv
    # as described in the python dev setup guide

    pip install --upgrade google-cloud-pubsub

    C++

    Weitere Informationen zur Installation der C++-Bibliothek finden Sie unter GitHub-README.

    C#

    Install-Package Google.Cloud.PubSub.V1 -Pre

    Go

    go get cloud.google.com/go/pubsub

    Java

    If you are using Maven, add the following to your pom.xml file. For more information about BOMs, see The Google Cloud Platform Libraries BOM.

    <dependencyManagement>
      <dependencies>
        <dependency>
          <groupId>com.google.cloud</groupId>
          <artifactId>libraries-bom</artifactId>
          <version>26.64.0</version>
          <type>pom</type>
          <scope>import</scope>
        </dependency>
      </dependencies>
    </dependencyManagement>
    
    <dependencies>
      <dependency>
        <groupId>com.google.cloud</groupId>
        <artifactId>google-cloud-pubsub</artifactId>
      </dependency>
    
    </dependencies>
    

    If you are using Gradle, add the following to your dependencies:

    implementation platform('com.google.cloud:libraries-bom:26.64.0')
    
    implementation 'com.google.cloud:google-cloud-pubsub'

    If you are using sbt, add the following to your dependencies:

    libraryDependencies += "com.google.cloud" % "google-cloud-pubsub" % "1.141.1"

    If you're using Visual Studio Code, IntelliJ, or Eclipse, you can add client libraries to your project using the following IDE plugins:

    The plugins provide additional functionality, such as key management for service accounts. Refer to each plugin's documentation for details.

    Node.js

    npm install @google-cloud/pubsub

    PHP

    composer require google/cloud-pubsub

    Ruby

    gem install google-cloud-pubsub

    Thema und Abo erstellen

    Nachdem Sie ein Thema erstellt haben, können Sie es abonnieren oder Nachrichten für das Thema veröffentlichen.

    Verwenden Sie den folgenden Befehl gcloud pubsub topics create, um ein Thema mit dem Namen my-topic zu erstellen. Ändern Sie den Namen des Themas nicht, da er im restlichen Teil des Tutorials verwendet wird.

    gcloud pubsub topics create my-topic

    Verwenden Sie den Befehl gcloud pubsub subscriptions create, um ein Abo zu erstellen. Nur Nachrichten, die nach dem Erstellen des Abos für das Thema veröffentlicht wurden, sind für Abonnentenanwendungen verfügbar.

    gcloud pubsub subscriptions create my-sub --topic my-topic

    Weitere Informationen zur Benennung von Themen und Abos finden Sie unter Ressourcennamen.

    Nachrichten veröffentlichen

    Bevor Sie die folgenden Beispiele ausführen, müssen Sie alle erforderlichen Werte, die im Code markiert sind, einkommentieren und eingeben. Dies ist erforderlich, um das Beispiel mit Ihrem Projekt und den Pub/Sub-Ressourcen zu verknüpfen, die Sie zuvor erstellt haben.

    Verwenden Sie my-topic als Themen-ID.

    Python

    from google.cloud import pubsub_v1
    
    # TODO(developer)
    # project_id = "your-project-id"
    # topic_id = "your-topic-id"
    
    publisher = pubsub_v1.PublisherClient()
    # The `topic_path` method creates a fully qualified identifier
    # in the form `projects/{project_id}/topics/{topic_id}`
    topic_path = publisher.topic_path(project_id, topic_id)
    
    for n in range(1, 10):
        data_str = f"Message number {n}"
        # Data must be a bytestring
        data = data_str.encode("utf-8")
        # When you publish a message, the client returns a future.
        future = publisher.publish(topic_path, data)
        print(future.result())
    
    print(f"Published messages to {topic_path}.")

    C++

    #include "google/cloud/pubsub/publisher.h"
    #include <iostream>
    
    int main(int argc, char* argv[]) try {
      if (argc != 3) {
        std::cerr << "Usage: " << argv[0] << " <project-id> <topic-id>\n";
        return 1;
      }
    
      std::string const project_id = argv[1];
      std::string const topic_id = argv[2];
    
      // Create a namespace alias to make the code easier to read.
      namespace pubsub = ::google::cloud::pubsub;
    
      auto publisher = pubsub::Publisher(
          pubsub::MakePublisherConnection(pubsub::Topic(project_id, topic_id)));
      auto id =
          publisher
              .Publish(pubsub::MessageBuilder{}.SetData("Hello World!").Build())
              .get();
      if (!id) throw std::move(id).status();
      std::cout << "Hello World published with id=" << *id << "\n";
    
      return 0;
    } catch (google::cloud::Status const& status) {
      std::cerr << "google::cloud::Status thrown: " << status << "\n";
      return 1;
    }

    C#

    
    using Google.Cloud.PubSub.V1;
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Threading;
    using System.Threading.Tasks;
    
    public class PublishMessagesAsyncSample
    {
        public async Task<int> PublishMessagesAsync(string projectId, string topicId, IEnumerable<string> messageTexts)
        {
            TopicName topicName = TopicName.FromProjectTopic(projectId, topicId);
            PublisherClient publisher = await PublisherClient.CreateAsync(topicName);
    
            int publishedMessageCount = 0;
            var publishTasks = messageTexts.Select(async text =>
            {
                try
                {
                    string message = await publisher.PublishAsync(text);
                    Console.WriteLine($"Published message {message}");
                    Interlocked.Increment(ref publishedMessageCount);
                }
                catch (Exception exception)
                {
                    Console.WriteLine($"An error occurred when publishing message {text}: {exception.Message}");
                }
            });
            await Task.WhenAll(publishTasks);
            return publishedMessageCount;
        }
    }

    Go

    import (
    	"context"
    	"fmt"
    	"io"
    
    	"cloud.google.com/go/pubsub/v2"
    )
    
    func publish(w io.Writer, projectID, topicID, msg string) error {
    	// projectID := "my-project-id"
    	// topicID := "my-topic"
    	// msg := "Hello World"
    	ctx := context.Background()
    	client, err := pubsub.NewClient(ctx, projectID)
    	if err != nil {
    		return fmt.Errorf("pubsub: NewClient: %w", err)
    	}
    	defer client.Close()
    
    	// client.Publisher can be passed a topic ID (e.g. "my-topic") or
    	// a fully qualified name (e.g. "projects/my-project/topics/my-topic").
    	// If a topic ID is provided, the project ID from the client is used.
    	// Reuse this publisher for all publish calls to send messages in batches.
    	publisher := client.Publisher(topicID)
    	result := publisher.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 fmt.Errorf("pubsub: result.Get: %w", err)
    	}
    	fmt.Fprintf(w, "Published a message; msg ID: %v\n", id)
    	return nil
    }
    

    Java

    
    import com.google.api.core.ApiFuture;
    import com.google.cloud.pubsub.v1.Publisher;
    import com.google.protobuf.ByteString;
    import com.google.pubsub.v1.PubsubMessage;
    import com.google.pubsub.v1.TopicName;
    import java.io.IOException;
    import java.util.concurrent.ExecutionException;
    import java.util.concurrent.TimeUnit;
    
    public class PublisherExample {
      public static void main(String... args) throws Exception {
        // TODO(developer): Replace these variables before running the sample.
        String projectId = "your-project-id";
        String topicId = "your-topic-id";
    
        publisherExample(projectId, topicId);
      }
    
      public static void publisherExample(String projectId, String topicId)
          throws IOException, ExecutionException, InterruptedException {
        TopicName topicName = TopicName.of(projectId, topicId);
    
        Publisher publisher = null;
        try {
          // Create a publisher instance with default settings bound to the topic
          publisher = Publisher.newBuilder(topicName).build();
    
          String message = "Hello World!";
          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> messageIdFuture = publisher.publish(pubsubMessage);
          String messageId = messageIdFuture.get();
          System.out.println("Published message ID: " + messageId);
        } finally {
          if (publisher != null) {
            // When finished with the publisher, shutdown to free up resources.
            publisher.shutdown();
            publisher.awaitTermination(1, TimeUnit.MINUTES);
          }
        }
      }
    }

    Node.js

    /**
     * TODO(developer): Uncomment these variables before running the sample.
     */
    // const topicNameOrId = 'YOUR_TOPIC_NAME_OR_ID';
    // const data = JSON.stringify({foo: 'bar'});
    
    // Imports the Google Cloud client library
    const {PubSub} = require('@google-cloud/pubsub');
    
    // Creates a client; cache this for further use
    const pubSubClient = new PubSub();
    
    async function publishMessage(topicNameOrId, data) {
      // Publishes the message as a string, e.g. "Hello, world!" or JSON.stringify(someObject)
      const dataBuffer = Buffer.from(data);
    
      // Cache topic objects (publishers) and reuse them.
      const topic = pubSubClient.topic(topicNameOrId);
    
      try {
        const messageId = await topic.publishMessage({data: dataBuffer});
        console.log(`Message ${messageId} published.`);
      } catch (error) {
        console.error(`Received error while publishing: ${error.message}`);
        process.exitCode = 1;
      }
    }

    Node.js

    /**
     * TODO(developer): Uncomment these variables before running the sample.
     */
    // const topicNameOrId = 'YOUR_TOPIC_NAME_OR_ID';
    // const data = JSON.stringify({foo: 'bar'});
    
    // Imports the Google Cloud client library
    import {PubSub} from '@google-cloud/pubsub';
    
    // Creates a client; cache this for further use
    const pubSubClient = new PubSub();
    
    async function publishMessage(topicNameOrId: string, data: string) {
      // Publishes the message as a string, e.g. "Hello, world!" or JSON.stringify(someObject)
      const dataBuffer = Buffer.from(data);
    
      // Cache topic objects (publishers) and reuse them.
      const topic = pubSubClient.topic(topicNameOrId);
    
      try {
        const messageId = await topic.publishMessage({data: dataBuffer});
        console.log(`Message ${messageId} published.`);
      } catch (error) {
        console.error(
          `Received error while publishing: ${(error as Error).message}`,
        );
        process.exitCode = 1;
      }
    }

    PHP

    use Google\Cloud\PubSub\MessageBuilder;
    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);
        $topic->publish((new MessageBuilder)->setData($message)->build());
    
        print('Message published' . PHP_EOL);
    }

    Ruby

    # topic_id = "your-topic-id"
    
    pubsub = Google::Cloud::PubSub.new
    
    publisher = pubsub.publisher topic_id
    
    publisher.publish "This is a test message."
    
    puts "Message published."

    Nachrichten empfangen

    Richten Sie einen Abonnenten ein, um die soeben veröffentlichten Nachrichten abzurufen. Jeder Abonnent muss die einzelnen Nachrichten innerhalb eines konfigurierbaren Zeitfensters bestätigen. Unbestätigte Nachrichten werden noch einmal zugestellt. Beachten Sie, dass Pub/Sub eine Nachricht mehrmals liefert, um sicherzustellen, dass alle Nachrichten mindestens einmal zu einem Abonnenten gelangen.

    Bevor Sie die folgenden Beispiele ausführen, müssen Sie alle erforderlichen Werte, die im Code markiert sind, einkommentieren und eingeben. Dies ist erforderlich, um das Beispiel mit Ihrem Projekt und den Pub/Sub-Ressourcen zu verknüpfen, die Sie zuvor erstellt haben.

    Verwenden Sie my-sub für Ihre Abo-ID.

    Weitere Beispiele, die zeigen, wie Nachrichten abgerufen werden, finden Sie unter Codebeispiele für Clientbibliotheken.

    Python

    from concurrent.futures import TimeoutError
    from google.cloud import pubsub_v1
    
    # TODO(developer)
    # project_id = "your-project-id"
    # subscription_id = "your-subscription-id"
    # Number of seconds the subscriber should listen for messages
    # timeout = 5.0
    
    subscriber = pubsub_v1.SubscriberClient()
    # The `subscription_path` method creates a fully qualified identifier
    # in the form `projects/{project_id}/subscriptions/{subscription_id}`
    subscription_path = subscriber.subscription_path(project_id, subscription_id)
    
    def callback(message: pubsub_v1.subscriber.message.Message) -> None:
        print(f"Received {message}.")
        message.ack()
    
    streaming_pull_future = subscriber.subscribe(subscription_path, callback=callback)
    print(f"Listening for messages on {subscription_path}..\n")
    
    # Wrap subscriber in a 'with' block to automatically call close() when done.
    with subscriber:
        try:
            # When `timeout` is not set, result() will block indefinitely,
            # unless an exception is encountered first.
            streaming_pull_future.result(timeout=timeout)
        except TimeoutError:
            streaming_pull_future.cancel()  # Trigger the shutdown.
            streaming_pull_future.result()  # Block until the shutdown is complete.

    C++

    #include "google/cloud/pubsub/message.h"
    #include "google/cloud/pubsub/subscriber.h"
    #include <iostream>
    
    int main(int argc, char* argv[]) try {
      if (argc != 3) {
        std::cerr << "Usage: " << argv[0] << " <project-id> <subscription-id>\n";
        return 1;
      }
    
      std::string const project_id = argv[1];
      std::string const subscription_id = argv[2];
    
      auto constexpr kWaitTimeout = std::chrono::seconds(30);
    
      // Create a namespace alias to make the code easier to read.
      namespace pubsub = ::google::cloud::pubsub;
    
      auto subscriber = pubsub::Subscriber(pubsub::MakeSubscriberConnection(
          pubsub::Subscription(project_id, subscription_id)));
    
      auto session =
          subscriber.Subscribe([&](pubsub::Message const& m, pubsub::AckHandler h) {
            std::cout << "Received message " << m << "\n";
            std::move(h).ack();
          });
    
      std::cout << "Waiting for messages on " + subscription_id + "...\n";
    
      // Blocks until the timeout is reached.
      auto result = session.wait_for(kWaitTimeout);
      if (result == std::future_status::timeout) {
        std::cout << "timeout reached, ending session\n";
        session.cancel();
      }
    
      return 0;
    } catch (google::cloud::Status const& status) {
      std::cerr << "google::cloud::Status thrown: " << status << "\n";
      return 1;
    }

    C#

    
    using Google.Cloud.PubSub.V1;
    using System;
    using System.Threading;
    using System.Threading.Tasks;
    
    public class PullMessagesAsyncSample
    {
        public async Task<int> PullMessagesAsync(string projectId, string subscriptionId, bool acknowledge)
        {
            SubscriptionName subscriptionName = SubscriptionName.FromProjectSubscription(projectId, subscriptionId);
            SubscriberClient subscriber = await SubscriberClient.CreateAsync(subscriptionName);
            // SubscriberClient runs your message handle function on multiple
            // threads to maximize throughput.
            int messageCount = 0;
            Task startTask = subscriber.StartAsync((PubsubMessage message, CancellationToken cancel) =>
            {
                string text = message.Data.ToStringUtf8();
                Console.WriteLine($"Message {message.MessageId}: {text}");
                Interlocked.Increment(ref messageCount);
                return Task.FromResult(acknowledge ? SubscriberClient.Reply.Ack : SubscriberClient.Reply.Nack);
            });
            // Run for 5 seconds.
            await Task.Delay(5000);
            await subscriber.StopAsync(CancellationToken.None);
            // Lets make sure that the start task finished successfully after the call to stop.
            await startTask;
            return messageCount;
        }
    }

    Go

    import (
    	"context"
    	"fmt"
    	"io"
    	"sync/atomic"
    	"time"
    
    	"cloud.google.com/go/pubsub/v2"
    )
    
    func pullMsgs(w io.Writer, projectID, subID string) error {
    	// projectID := "my-project-id"
    	// subID := "my-sub"
    	ctx := context.Background()
    	client, err := pubsub.NewClient(ctx, projectID)
    	if err != nil {
    		return fmt.Errorf("pubsub.NewClient: %w", err)
    	}
    	defer client.Close()
    
    	// client.Subscriber can be passed a subscription ID (e.g. "my-sub") or
    	// a fully qualified name (e.g. "projects/my-project/subscriptions/my-sub").
    	// If a subscription ID is provided, the project ID from the client is used.
    	sub := client.Subscriber(subID)
    
    	// Receive messages for 10 seconds, which simplifies testing.
    	// Comment this out in production, since `Receive` should
    	// be used as a long running operation.
    	ctx, cancel := context.WithTimeout(ctx, 10*time.Second)
    	defer cancel()
    
    	var received int32
    	err = sub.Receive(ctx, func(_ context.Context, msg *pubsub.Message) {
    		fmt.Fprintf(w, "Got message: %q\n", string(msg.Data))
    		atomic.AddInt32(&received, 1)
    		msg.Ack()
    	})
    	if err != nil {
    		return fmt.Errorf("sub.Receive: %w", err)
    	}
    	fmt.Fprintf(w, "Received %d messages\n", received)
    
    	return nil
    }
    

    Java

    
    import com.google.cloud.pubsub.v1.AckReplyConsumer;
    import com.google.cloud.pubsub.v1.MessageReceiver;
    import com.google.cloud.pubsub.v1.Subscriber;
    import com.google.pubsub.v1.ProjectSubscriptionName;
    import com.google.pubsub.v1.PubsubMessage;
    import java.util.concurrent.TimeUnit;
    import java.util.concurrent.TimeoutException;
    
    public class SubscribeAsyncExample {
      public static void main(String... args) throws Exception {
        // TODO(developer): Replace these variables before running the sample.
        String projectId = "your-project-id";
        String subscriptionId = "your-subscription-id";
    
        subscribeAsyncExample(projectId, subscriptionId);
      }
    
      public static void subscribeAsyncExample(String projectId, String subscriptionId) {
        ProjectSubscriptionName subscriptionName =
            ProjectSubscriptionName.of(projectId, subscriptionId);
    
        // Instantiate an asynchronous message receiver.
        MessageReceiver receiver =
            (PubsubMessage message, AckReplyConsumer consumer) -> {
              // Handle incoming message, then ack the received message.
              System.out.println("Id: " + message.getMessageId());
              System.out.println("Data: " + message.getData().toStringUtf8());
              consumer.ack();
            };
    
        Subscriber subscriber = null;
        try {
          subscriber = Subscriber.newBuilder(subscriptionName, receiver).build();
          // Start the subscriber.
          subscriber.startAsync().awaitRunning();
          System.out.printf("Listening for messages on %s:\n", subscriptionName.toString());
          // Allow the subscriber to run for 30s unless an unrecoverable error occurs.
          subscriber.awaitTerminated(30, TimeUnit.SECONDS);
        } catch (TimeoutException timeoutException) {
          // Shut down the subscriber after 30s. Stop receiving messages.
          subscriber.stopAsync();
        }
      }
    }

    Node.js

    /**
     * TODO(developer): Uncomment these variables before running the sample.
     */
    // const subscriptionNameOrId = 'YOUR_SUBSCRIPTION_NAME_OR_ID';
    // const timeout = 60;
    
    // Imports the Google Cloud client library
    const {PubSub} = require('@google-cloud/pubsub');
    
    // Creates a client; cache this for further use
    const pubSubClient = new PubSub();
    
    function listenForMessages(subscriptionNameOrId, timeout) {
      // References an existing subscription; if you are unsure if the
      // subscription will exist, try the optimisticSubscribe sample.
      const subscription = pubSubClient.subscription(subscriptionNameOrId);
    
      // Create an event handler to handle messages
      let messageCount = 0;
      const messageHandler = message => {
        console.log(`Received message ${message.id}:`);
        console.log(`\tData: ${message.data}`);
        console.log(`\tAttributes: ${message.attributes}`);
        messageCount += 1;
    
        // "Ack" (acknowledge receipt of) the message
        message.ack();
      };
    
      // Listen for new messages until timeout is hit
      subscription.on('message', messageHandler);
    
      // Wait a while for the subscription to run. (Part of the sample only.)
      setTimeout(() => {
        subscription.removeListener('message', messageHandler);
        console.log(`${messageCount} message(s) received.`);
      }, timeout * 1000);
    }

    PHP

    use Google\Cloud\PubSub\PubSubClient;
    
    /**
     * Pulls all Pub/Sub messages for a subscription.
     *
     * @param string $projectId  The Google project ID.
     * @param string $subscriptionName  The Pub/Sub subscription name.
     */
    function pull_messages($projectId, $subscriptionName)
    {
        $pubsub = new PubSubClient([
            'projectId' => $projectId,
        ]);
        $subscription = $pubsub->subscription($subscriptionName);
        foreach ($subscription->pull() as $message) {
            printf('Message: %s' . PHP_EOL, $message->data());
            // Acknowledge the Pub/Sub message has been received, so it will not be pulled multiple times.
            $subscription->acknowledge($message);
        }
    }

    Ruby

    # subscription_id = "your-subscription-id"
    
    pubsub = Google::Cloud::PubSub.new
    
    subscriber = pubsub.subscriber subscription_id
    
    listener = subscriber.listen do |received_message|
      puts "Received message: #{received_message.data}"
      received_message.acknowledge!
    end
    
    listener.start
    # Let the main thread sleep for 60 seconds so the thread for listening
    # messages does not quit
    sleep 60
    listener.stop.wait!

    Wie ist es gelaufen?

    Bereinigen (optional)

    1. Um zu vermeiden, dass Ihrem Google Cloud -Konto die in diesem Leitfaden verwendeten Ressourcen in Rechnung gestellt werden, können Sie das Thema und das Abo über die Befehlszeile löschen.
        gcloud pubsub subscriptions delete my-sub
        gcloud pubsub topics delete my-topic
    2. Optional: Revoke the authentication credentials that you created, and delete the local credential file.

      gcloud auth application-default revoke
    3. Optional: Revoke credentials from the gcloud CLI.

      gcloud auth revoke

    Nächste Schritte