Change subscription types

After you create a subscription, you can change the delivery method to push, pull, or export.

Before you begin

• Create one of the supported subscriptions.

Required roles and permissions

To get the permissions that you need to change subscription types and manage them, ask your administrator to grant you the Pub/Sub Editor (roles/pubsub.editor) IAM role on your topic or project. For more information about granting roles, see Manage access to projects, folders, and organizations.

This predefined role contains the permissions required to change subscription types and manage them. To see the exact permissions that are required, expand the Required permissions section:

Required permissions

The following permissions are required to change subscription types and manage them:

• Pull from a subscription: pubsub.subscriptions.consume
• Create a subscription: pubsub.subscriptions.create
• Delete a subscription: pubsub.subscriptions.delete
• Get a subscription: pubsub.subscriptions.get
• List a subscription: pubsub.subscriptions.list
• Update a subscription: pubsub.subscriptions.update
• Attach a subscription to a topic: pubsub.topics.attachSubscription
• Get the IAM policy for a subscription: pubsub.subscriptions.getIamPolicy
• Configure the IAM policy for a subscription: pubsub.subscriptions.setIamPolicy

You might also be able to get these permissions with custom roles or other predefined roles.

You can configure access control at the project level and at the individual resource level. You can create a subscription in one project and attach it to a topic located in a different project. Ensure that you have the required permissions for each project.

Modify delivery methods

You can switch between different subscription types.

Console

To modify a subscription, complete the following steps.

1. In the Google Cloud console, go to the Subscriptions page.

   Go to Subscriptions

2. Click next to the subscription to update.
3. In the Delivery type, choose a delivery option.
4. Fill in other subscription properties as required.
5. Click Update.

gcloud

1. In the Google Cloud console, activate Cloud Shell.

   Activate Cloud Shell

   At the bottom of the Google Cloud console, a Cloud Shell session starts and displays a command-line prompt. Cloud Shell is a shell environment with the Google Cloud CLI already installed and with values already set for your current project. It can take a few seconds for the session to initialize.

2. To modify the push endpoint URL, run the gcloud pubsub subscriptions modify-push-config command:

   gcloud pubsub subscriptions modify-push-config SUBSCRIPTION_ID \
       --push-endpoint=PUSH_ENDPOINT

   If the subscription is already using pull delivery, setting the push endpoint switches the delivery method to push delivery.

   You can switch from push to pull delivery by changing the push endpoint to an empty string.

REST

To modify the push configurations of a subscription, use the projects.subscriptions.modifyPushConfig method:

Request:

The request must be authenticated with an access token in the Authorization header. To obtain an access token for the current Application Default Credentials: gcloud auth application-default print-access-token.

POST https://pubsub.googleapis.com/v1/projects/PROJECT_ID/subscriptions/SUBSCRIPTION_ID:modifyPushConfig
Authorization: Bearer ACCESS_TOKEN
    

Request body:

{
  "pushConfig": {
    "pushEndpoint": "PUSH_ENDPOINT"
  }
}

Where:

PROJECT_ID is your project ID.

SUBSCRIPTION_ID is your subscription ID.

PUSH_ENDPOINT is a modified URL to you want to apply as your new push endpoint. For example, https://myproject.appspot.com/myhandler.

Response:

If the request is successful, the response is an empty JSON object.

C++

Before trying this sample, follow the C++ setup instructions in the Pub/Sub quickstart using client libraries. For more information, see the Pub/Sub C++ API reference documentation.

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

namespace pubsub_admin = ::google::cloud::pubsub_admin;
namespace pubsub = ::google::cloud::pubsub;
[](pubsub_admin::SubscriptionAdminClient client,
   std::string const& project_id, std::string const& subscription_id,
   std::string const& endpoint) {
  google::pubsub::v1::ModifyPushConfigRequest request;
  request.set_subscription(
      pubsub::Subscription(project_id, subscription_id).FullName());
  request.mutable_push_config()->set_push_endpoint(endpoint);
  auto status = client.ModifyPushConfig(request);
  if (!status.ok()) throw std::runtime_error(status.message());

  std::cout << "The subscription push configuration was successfully"
            << " modified\n";
}

C#

Before trying this sample, follow the C# setup instructions in the Pub/Sub quickstart using client libraries. For more information, see the Pub/Sub C# API reference documentation.

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

using Google.Cloud.PubSub.V1;

public class UpdatePushConfigurationSample
{
    public void UpdatePushConfiguration(string projectId, string subscriptionId, string pushEndpoint)
    {
        SubscriberServiceApiClient subscriber = SubscriberServiceApiClient.Create();
        SubscriptionName subscriptionName = SubscriptionName.FromProjectSubscription(projectId, subscriptionId);

        PushConfig pushConfig = new PushConfig { PushEndpoint = pushEndpoint };

        subscriber.ModifyPushConfig(subscriptionName, pushConfig);
    }
}

Go

Before trying this sample, follow the Go setup instructions in the Pub/Sub quickstart using client libraries. For more information, see the Pub/Sub Go API reference documentation.

To authenticate to Pub/Sub, 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/pubsub"
)

func updateEndpoint(w io.Writer, projectID, subID string, endpoint string) error {
	// projectID := "my-project-id"
	// subID := "my-sub"
	// endpoint := "https://my-test-project.appspot.com/push"
	ctx := context.Background()
	client, err := pubsub.NewClient(ctx, projectID)
	if err != nil {
		return fmt.Errorf("pubsub.NewClient: %w", err)
	}
	defer client.Close()

	subConfig, err := client.Subscription(subID).Update(ctx, pubsub.SubscriptionConfigToUpdate{
		PushConfig: &pubsub.PushConfig{Endpoint: endpoint},
	})
	if err != nil {
		return fmt.Errorf("Update: %w", err)
	}
	fmt.Fprintf(w, "Updated subscription config: %v\n", subConfig)
	return nil
}

Java

Before trying this sample, follow the Java setup instructions in the Pub/Sub quickstart using client libraries. For more information, see the Pub/Sub Java API reference documentation.

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

import com.google.cloud.pubsub.v1.SubscriptionAdminClient;
import com.google.pubsub.v1.PushConfig;
import com.google.pubsub.v1.Subscription;
import com.google.pubsub.v1.SubscriptionName;
import java.io.IOException;

public class UpdatePushConfigurationExample {
  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";
    String pushEndpoint = "https://my-test-project.appspot.com/push";

    updatePushConfigurationExample(projectId, subscriptionId, pushEndpoint);
  }

  public static void updatePushConfigurationExample(
      String projectId, String subscriptionId, String pushEndpoint) throws IOException {
    try (SubscriptionAdminClient subscriptionAdminClient = SubscriptionAdminClient.create()) {
      SubscriptionName subscriptionName = SubscriptionName.of(projectId, subscriptionId);
      PushConfig pushConfig = PushConfig.newBuilder().setPushEndpoint(pushEndpoint).build();
      subscriptionAdminClient.modifyPushConfig(subscriptionName, pushConfig);
      Subscription subscription = subscriptionAdminClient.getSubscription(subscriptionName);
      System.out.println(
          "Updated push endpoint to: " + subscription.getPushConfig().getPushEndpoint());
    }
  }
}

Node.js

/**
 * TODO(developer): Uncomment these variables before running the sample.
 */
// const topicNameOrId = 'YOUR_TOPIC_NAME_OR_ID';
// const subscriptionNameOrId = 'YOUR_SUBSCRIPTION_NAME_OR_ID';

// 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 modifyPushConfig(topicNameOrId, subscriptionNameOrId) {
  const options = {
    // Set to an HTTPS endpoint of your choice. If necessary, register
    // (authorize) the domain on which the server is hosted.
    pushEndpoint: `https://${pubSubClient.projectId}.appspot.com/push`,
  };

  await pubSubClient
    .topic(topicNameOrId)
    .subscription(subscriptionNameOrId)
    .modifyPushConfig(options);
  console.log(`Modified push config for subscription ${subscriptionNameOrId}.`);
}

Node.js

/**
 * TODO(developer): Uncomment these variables before running the sample.
 */
// const topicNameOrId = 'YOUR_TOPIC_NAME_OR_ID';
// const subscriptionNameOrId = 'YOUR_SUBSCRIPTION_NAME_OR_ID';

// Imports the Google Cloud client library
import {PubSub, CreateSubscriptionOptions} from '@google-cloud/pubsub';

// Creates a client; cache this for further use
const pubSubClient = new PubSub();

async function modifyPushConfig(
  topicNameOrId: string,
  subscriptionNameOrId: string
) {
  const options: CreateSubscriptionOptions = {
    // Set to an HTTPS endpoint of your choice. If necessary, register
    // (authorize) the domain on which the server is hosted.
    pushEndpoint: `https://${pubSubClient.projectId}.appspot.com/push`,
  };

  await pubSubClient
    .topic(topicNameOrId)
    .subscription(subscriptionNameOrId)
    .modifyPushConfig(options);
  console.log(`Modified push config for subscription ${subscriptionNameOrId}.`);
}

Python

Before trying this sample, follow the Python setup instructions in the Pub/Sub quickstart using client libraries. For more information, see the Pub/Sub Python API reference documentation.

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

from google.cloud import pubsub_v1

# TODO(developer)
# project_id = "your-project-id"
# topic_id = "your-topic-id"
# subscription_id = "your-subscription-id"
# endpoint = "https://my-test-project.appspot.com/push"

subscriber = pubsub_v1.SubscriberClient()
subscription_path = subscriber.subscription_path(project_id, subscription_id)

push_config = pubsub_v1.types.PushConfig(push_endpoint=endpoint)

subscription = pubsub_v1.types.Subscription(
    name=subscription_path, topic=topic_id, push_config=push_config
)

update_mask = {"paths": {"push_config"}}

# Wrap the subscriber in a 'with' block to automatically call close() to
# close the underlying gRPC channel when done.
with subscriber:
    result = subscriber.update_subscription(
        request={"subscription": subscription, "update_mask": update_mask}
    )

print(f"Subscription updated: {subscription_path}")
print(f"New endpoint for subscription is: {result.push_config}.")

Ruby

Before trying this sample, follow the Ruby setup instructions in the Pub/Sub quickstart using client libraries. For more information, see the Pub/Sub Ruby API reference documentation.

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

# subscription_id   = "your-subscription-id"
# new_endpoint      = "Endpoint where your app receives messages""

pubsub = Google::Cloud::Pubsub.new

subscription          = pubsub.subscription subscription_id
subscription.endpoint = new_endpoint

puts "Push endpoint updated."

Note: Switching from a push to a pull subscription takes several minutes to complete. In this interval, pull requests might generate errors and push requests might continue.

What's next

• Create or modify a subscription with gcloud commands.
• Create or modify a subscription with REST APIs.