Create a new Pub/Sub notification

Add a Pub/Sub notification to a Cloud Storage bucket.

Explore further

For detailed documentation that includes this code sample, see the following:

Code sample

C++

For more information, see the Cloud Storage C++ API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

namespace gcs = ::google::cloud::storage;
using ::google::cloud::StatusOr;
[](gcs::Client client, std::string const& bucket_name,
   std::string const& topic_name) {
  StatusOr<gcs::NotificationMetadata> notification =
      client.CreateNotification(bucket_name, topic_name,
                                gcs::NotificationMetadata());
  if (!notification) throw std::move(notification).status();

  std::cout << "Successfully created notification " << notification->id()
            << " for bucket " << bucket_name << "\n";
  std::cout << "Full details for the notification:\n"
            << *notification << "\n";
}

C#

For more information, see the Cloud Storage C# API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.


using Google.Apis.Storage.v1.Data;
using Google.Cloud.Storage.V1;
using System;

public class CreatePubSubNotificationSample
{
    public Notification CreatePubSubNotification(
        string bucketName = "your-unique-bucket-name",
        string topic = "my-topic")
    {
        StorageClient storage = StorageClient.Create();
        Notification notification = new Notification
        {
            Topic = topic,
            PayloadFormat = "JSON_API_V1"
        };

        Notification createdNotification = storage.CreateNotification(bucketName, notification);
        Console.WriteLine("Notification subscription created with ID: " + createdNotification.Id + " for bucket name " + bucketName);
        return createdNotification;
    }
}

Go

For more information, see the Cloud Storage Go API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

import (
	"context"
	"fmt"
	"io"

	"cloud.google.com/go/storage"
)

// createBucketNotification creates a notification configuration for a bucket.
func createBucketNotification(w io.Writer, projectID, bucketName, topic string) error {
	// projectID := "my-project-id"
	// bucketName := "bucket-name"
	// topic := "topic-name"

	ctx := context.Background()
	client, err := storage.NewClient(ctx)
	if err != nil {
		return fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close()

	notification := storage.Notification{
		TopicID:        topic,
		TopicProjectID: projectID,
		PayloadFormat:  storage.JSONPayload,
	}

	createdNotification, err := client.Bucket(bucketName).AddNotification(ctx, &notification)
	if err != nil {
		return fmt.Errorf("Bucket.AddNotification: %w", err)
	}
	fmt.Fprintf(w, "Successfully created notification with ID %s for bucket %s.\n", createdNotification.ID, bucketName)
	return nil
}

Java

For more information, see the Cloud Storage Java API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

import com.google.cloud.storage.Notification;
import com.google.cloud.storage.NotificationInfo;
import com.google.cloud.storage.NotificationInfo.EventType;
import com.google.cloud.storage.NotificationInfo.PayloadFormat;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;
import java.util.Map;

public class CreateBucketPubSubNotification {

  public static void createBucketPubSubNotification(
      String bucketName,
      String topicName,
      Map<String, String> customAttributes,
      EventType[] eventTypes,
      String objectNamePrefix,
      PayloadFormat payloadFormat) {
    // The ID to give your GCS bucket
    // String bucketName = "your-unique-bucket-name";

    // The name of the topic you would like to create a notification for
    // String topicName = "projects/{your-project}/topics/{your-topic}";

    // Any custom attributes
    // Map<String, String> customAttributes = Map.of("label", "value");

    // The object name prefix for which this notification configuration applies
    // String objectNamePrefix = "blob-";

    // Desired content of the Payload
    // PayloadFormat payloadFormat = PayloadFormat.JSON_API_V1.JSON_API_V1;

    Storage storage = StorageOptions.newBuilder().build().getService();
    NotificationInfo notificationInfo =
        NotificationInfo.newBuilder(topicName)
            .setCustomAttributes(customAttributes)
            .setEventTypes(eventTypes)
            .setObjectNamePrefix(objectNamePrefix)
            .setPayloadFormat(payloadFormat)
            .build();
    Notification notification = storage.createNotification(bucketName, notificationInfo);
    String topic = notification.getTopic();
    System.out.println("Successfully created notification for topic " + topic);
  }
}

Node.js

For more information, see the Cloud Storage Node.js API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

/**
 * TODO(developer): Uncomment the following lines before running the sample.
 */
// The ID of your GCS bucket
// const bucketName = 'your-unique-bucket-name';

// The name of a topic
// const topic = 'my-topic';

// Imports the Google Cloud client library
const {Storage} = require('@google-cloud/storage');

// Creates a client
const storage = new Storage();

async function createNotification() {
  // Creates a notification
  await storage.bucket(bucketName).createNotification(topic);

  console.log('Notification subscription created.');
}

createNotification().catch(console.error);

PHP

For more information, see the Cloud Storage PHP API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

use Google\Cloud\Storage\StorageClient;

/**
 * Creates a notification configuration for a bucket.
 * This sample is used on this page:
 *   https://cloud.google.com/storage/docs/reporting-changes
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 * @param string $topicName The name of the topic you would like to create a notification.
 *        (e.g. 'my-topic')
 */
function create_bucket_notifications(
    string $bucketName,
    string $topicName
): void {
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);
    $notification = $bucket->createNotification($topicName);

    printf(
        'Successfully created notification with ID %s for bucket %s in topic %s' . PHP_EOL,
        $notification->id(),
        $bucketName,
        $topicName
    );
}

Python

For more information, see the Cloud Storage Python API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

from google.cloud import storage


def create_bucket_notifications(bucket_name, topic_name):
    """Creates a notification configuration for a bucket."""
    # The ID of your GCS bucket
    # bucket_name = "your-bucket-name"
    # The name of a topic
    # topic_name = "your-topic-name"

    storage_client = storage.Client()
    bucket = storage_client.bucket(bucket_name)
    notification = bucket.notification(topic_name=topic_name)
    notification.create()

    print(f"Successfully created notification with ID {notification.notification_id} for bucket {bucket_name}")

Ruby

For more information, see the Cloud Storage Ruby API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

require "google/cloud/storage"

def create_bucket_notifications bucket_name:, topic_name:
  # The ID of your GCS bucket
  # bucket_name = "your-unique-bucket-name"

  # The ID of the pubsub topic
  # topic_name = "your-unique-topic-name"

  storage = Google::Cloud::Storage.new
  bucket  = storage.bucket bucket_name
  notification = bucket.create_notification topic_name

  puts "Successfully created notification with ID #{notification.id} for bucket #{bucket_name}"
end

What's next

To search and filter code samples for other Google Cloud products, see the Google Cloud sample browser.