Configuring Cloud Pub/Sub notifications

You can receive notifications of changes to your GCP repositories using Cloud Pub/Sub. These notifications inform you when a user creates a new repository, deletes a repository, or pushes a change to an existing repository. You can choose to configure notifications for specific repositories or or across an entire project.

To learn more about Cloud Pub/Sub, see the What is Google Cloud Pub/Sub? topic.

Before you begin

• If you have not already done so, follow the steps in the Quickstart to create a project, install Git, and initialize the Google Cloud SDK.
• Verify that you have the appropriate permissions to create topics and subscriptions. For more information, see Access Control.

Create a Cloud Pub/Sub topic

For each Cloud Source Repositories project or repository for which you'd like notifications, you need to create a Cloud Pub/Sub topic. You can create a topic using either the console or the gcloud command-line tool.

When you create a topic, you need to use a qualified URI for your repository. The qualified URI is:

projects/[PROJECT_ID]/topics/[TOPIC_NAME]

where [PROJECT_ID] is your Google Cloud Platform project ID and [TOPIC_NAME] is the name of the topic.

To create a topic:

Console

1. Go to the Cloud Pub/Sub topics page in the GCP Console.

   Go to the Cloud Pub/Sub topics page

2. Click Create Topic.

3. Enter a topic name with the URI:

   projects/[PROJECT-ID]/topics/[TOPIC_NAME]
   

   where [PROJECT-ID] is your Google Cloud Platform project ID.

4. Click Create.

gcloud

From a terminal window, run the following command:

gcloud alpha pubsub topics create projects/[PROJECT-ID]/topics/[TOPIC_NAME]

Note: If this command returns a "Resource already exists in the project" error, you may already have a Cloud Source Repositories topic.

To learn more about the gcloud alpha pubsub topics command, see the topics documentation.

Create a Cloud Pub/Sub subscription

To receive events published to a topic, you need to create a Pub/Sub subscription.

A subscriber application receives messages from your repository's topic. Subscribers can respond to your repository events by sending notifications or triggering a build.

To create a subscription:

Console

1. Go to the Cloud Pub/Sub topics page in the GCP Console.

   Go to the Cloud Pub/Sub topics page

2. Click your project's topic.

3. Click Create Subscription.

4. Enter a subscription name:

   projects/[PROJECT-ID]/subscriptions/[SUBSCRIPTION_NAME]
   

   Leave Delivery Type set to Pull.

5. Click Create.

gcloud

From a terminal window, run the following command:

gcloud alpha pubsub subscriptions create [SUBSCRIPTION_NAME] --topic=[TOPIC_NAME]

Note: Use the optional flag --ack-deadline to configure how many seconds the system will wait for acknowledgement from the subscriber before re-attempting delivery. Without this flag, the default deadline is 10 seconds.

To learn more about the gcloud alpha pubsub subscriptions command, see the subscriptions documentation.

Add a topic

You can add an association between a project or repository and a Cloud Pub/Sub topic using the gcloud command-line tool.

To add a topic to an entire project, type the following command:

gcloud beta source project-configs update --add-topic=[TOPIC_NAME]

To add a topic to a specific repository, type the following command:

gcloud beta source repos update [REPOSITORY_NAME] --add-topic=[TOPIC_NAME]

Note: For information on how to delete a Cloud Pub/Sub topic, see Managing Topics and Subscriptions.

Remove a topic

You can remove an association between a project or repository and a Cloud Pub/Sub topic using the gcloud command-line tool.

To remove a topic from an entire project, type the following command:

gcloud beta source project-configs update --remove-topic=[TOPIC_NAME]

To remove a topic from a specific repository, type the following command:

gcloud beta source repos update [REPOSITORY_NAME] --remove-topic=[TOPIC_NAME]

Note: For information on how to delete a Cloud Pub/Sub topic, see Managing Topics and Subscriptions.

Set the topic format

Notifications for Cloud Source Repositories can use either JSON or Protocol Buffers format. To set the format for a topic, you can use the --message-format parameter when you add the topic, such as:

gcloud beta source project-configs update --add-topic=[TOPIC_NAME] --message-format=[json|protobuf]

You can also use the set-format command:

gcloud beta source project-configs update --update-topic[TOPIC_NAME] --message-format=[json|protobuf]

What's next

• Learn more about Cloud Pub/Sub Notifications for Google Cloud Source Repositories.
• Read the Cloud Pub/Sub documentation.
• For an in-depth explanation of Cloud Pub/Sub, see What is Google Cloud/Pub Sub?
• Learn more about Cloud Pub/Sub access control roles.