Create and manage build triggers

A Cloud Build trigger automatically starts a build whenever you make any changes to your source code. You can configure the trigger to build your code on any changes to the source repository or only changes that match certain criteria.

This page explains how to connect to source repositories such as GitHub and Bitbucket, and create build triggers to build the code in the repositories.

Before you begin

  • Enable the Cloud Build API.

    Enable the API

  • You need to have the Cloud Build Editor (roles/cloudbuild.builds.editor) role in your project to create triggers.
  • You need source code in Cloud Source Repositories, GitHub, or Bitbucket.
  • You need either a Dockerfile or a Cloud Build config file.

Connect to source repositories

You must first connect Cloud Build to your source repository before building the code in that repository. Your repositories in Cloud Source Repositories are connected to Cloud Build by default. You can directly create triggers for your repositories in Cloud Source Repositories without manually connecting to them.

If you are connecting an external repository, such as one hosted on GitHub or Bitbucket, you will need admin-level permissions on the repository to initially connect your repository to Cloud Build. Admin permissions are not required to create triggers in a repository that is already connected to Cloud Build.

Complete the following steps to connect to GitHub or Bitbucket:

  1. Open the Triggers page in the Google Cloud console.

    Open the triggers page

  2. Select your project and click Open.

  3. Select the region where you would like to create your trigger from the Region drop-down menu.

  4. Click Connect Repository.

  5. Select the repository where you've stored your source code.

    If you select GitHub (mirrored) or Bitbucket (mirrored) as your source repository, Cloud Build mirrors your repository in Cloud Source Repositories and uses the mirrored repository for all its operations.

  6. Click Continue.

  7. Authenticate to your source repository with your username and password.

  8. From the list of available repositories, select the repository, then click Connect.

    For external repositories, such as GitHub and Bitbucket, you must have owner-level permissions for the Google Cloud project with which you're working.

  9. Click Create a trigger to continue creating a build trigger to automate builds for the source code in the repository, or click Done.

Creating a build trigger

Console

  1. Open the Triggers page in the Google Cloud console.

    Open the Triggers page

  2. Select your project from the project selector drop-down menu at the top of the page.

  3. Click Open.

  4. Click Create trigger.

  5. Enter the following trigger settings:

    • Name: Enter a name for your trigger.

    • Region: Select the region for your trigger.

      If the build config file associated with your trigger specifies a private pool, the region you select for your trigger must match the region of the private pool.

      If you select global as your region, Cloud Build uses the region specified in your build config file to run your build. This can either be the region of the private pool, if you specify a private pool in your build config file, or the global default pool if you don't specify a private pool.

    • Description (optional): Enter a description for your trigger.

    • Event: Select the repository event to invoke your trigger.

      • Push to a branch: Set your trigger to start a build on commits to a particular branch.

      • Push new tag: Set your trigger to start a build on commits that contain a particular tag.

      • Pull request: Set your trigger to start a build on commits to a pull request.

    • Source: Select 1st generation or 2nd generation as your source. You can only connect repositories from GitHub and GitHub Enterprise when selecting 2nd generation as your source. To learn more, see Cloud Build repositories.

      • Branch or Tag: Specify a regular expression with the branch or tag value to match. Forward slashes (/) cannot be used in tags. For more information on acceptable regular expression syntax, see RE2 syntax.

        When your build executes, Cloud Build copies the contents of your repository to /workspace, the default working directory for Cloud Build. Learn more about working directories on the Build configuration overview page.

        To only allow builds from specific sources, set an organization policy for allowed integrations (constraints/cloudbuild.allowedIntegrations) to deny interaction with the source defined in your trigger. The organization policy overrides the trigger and your build is not executed. To learn more, see Gate builds on organization policy for your project.

    • Included files (optional): Changes affecting at least one of these files will invoke a build. You can use glob strings to specify multiple files with wildcard characters. Acceptable wildcard characters include the characters supported by Go Match, **, and alternation.

    • Ignored files (optional): Changes only affecting ignored files won't invoke a build. You can use glob strings to specify multiple files with wildcard characters. Acceptable wildcard characters include the characters supported by Go Match, **, and alternation.

      If you specify a file in both Included files and Ignored files, changes to that file will not invoke a build. Say you specify **/README.md in Ignored files to ignore README.md in any directory, and specify src/* in Included files to start a build on changes to any file in the folder src/. Now if you make a change to src/README.md, Cloud Build won't start a build. Each time you push a change to your source, Cloud Build looks through your changed files for included and ignored files to determine whether a build should be invoked:

      • If you push a change to your repository on an existing branch, Cloud Build looks at the files changed between the commit you just pushed and the commit to which the branch previously pointed.
      • If your repository is Cloud Source Repository and you push a change to a newly created branch, then Cloud Build treats all the files in the repository as changed files.
      • If you delete a branch, Cloud Build does not start a build.
    • Configuration: Select the build config file located in your remote repository or create an inline build config file to use for your build.

      • Type: Select the type of configuration to use for your build.
        • Cloud Build configuration file (yaml or json): Use a build config file for your configuration.
        • Dockerfile: Use a Dockerfile for your configuration.
        • Buildpacks: Use buildpacks for your configuration.
      • Location: Specify the location for your configuration.

        • Repository: If your config file is located in your remote repository, provide the location of your build config file, the Dockerfile directory, or the buildpacks directory. If your build config type is a Dockerfile or a buildpack, then you need to provide a name for the resulting image and optionally, a timeout for your build. When you've provided the Dockerfile or buildpack image name, you'll see a preview of the docker build or pack command that your build will execute.
        • Buildpack environment variables (optional): If you selected buildpacks as your configuration type, click Add pack environment variable to specify your buildpack environment variables and values. To learn more about buildpack environment variables, see Environment variables.
        • Inline: If you selected Cloud Build configuration file (yaml or json) as your configuration option, you can specify your build config inline. Click Open Editor to write your build config file in the Google Cloud console using YAML or JSON syntax. Click Done to save your build config.

    • Use private pool: This field appears if you selected Dockerfile as your Configuration option. Select this checkbox if you're running your build in a private pool.

    • Private pool: If you selected Use private pool, specify the resource name of the private pool of the form projects/WORKERPOOL_PROJECT_ID/locations/REGION/workerPools/WORKERPOOL_ID.

    • Substitution variables (optional): If you selected the Cloud Build config file as your build config option, you can choose to define trigger-specific substitution variables using this field. For example, say you're creating multiple triggers where each trigger deploys your app to a specific environment. You can specify that your app is deployed to an environment in your build config file and then use this field to define substitution variables specifying which environment this trigger should deploy to. For information on specifying substitution values in build config files, see Substituting variable values.

    • Approval (optional): Check the box to require approval before your build executes.

    • Service account: Select the service account to use when invoking your trigger. If you don't select a service account, the Cloud Build legacy service account is used if it is available to your project.

  6. Click Create to save your build trigger.

gcloud

To create a trigger if your source code is in Cloud Source Repositories:

    gcloud builds triggers create cloud-source-repositories \
    --repo=REPO_NAME \
    --branch-pattern=BRANCH_PATTERN \ # or --tag-pattern=TAG_PATTERN
    --build-config=BUILD_CONFIG_FILE \
    --service-account=SERVICE_ACCOUNT \
    --require-approval

Where:

  • REPO_NAME is the name of your repository.
  • BRANCH_PATTERN is the branch name in your repository to invoke the build on.
  • TAG_PATTERN is the tag name in your repository to invoke the build on.
  • BUILD_CONFIG_FILE is the path to your build configuration file.
  • SERVICE_ACCOUNT is the email associated with your service account. If you don't include this flag, the Cloud Build legacy service account is used if it is available to your project.
  • Optional: --require-approval is the flag to include to configure your trigger to require approval.

For a complete list of flags, see the gcloud reference for how to create triggers for Cloud Source Repositories.

To create a trigger if your source code is in GitHub:

    gcloud builds triggers create github \
    --region=REGION \
    --repo-name=REPO_NAME \
    --repo-owner=REPO_OWNER \
    --branch-pattern=BRANCH_PATTERN \ # or --tag-pattern=TAG_PATTERN
    --build-config=BUILD_CONFIG_FILE \
    --service-account=SERVICE_ACCOUNT \
    --require-approval
    --include-logs-with-status

Where:

  • REGION is the region for your trigger.
  • REPO_NAME is the name of your repository.
  • REPO_OWNER is the username of the repository owner.
  • BRANCH_PATTERN is the branch name in your repository to invoke the build on.
  • TAG_PATTERN is the tag name in your repository to invoke the build on.
  • BUILD_CONFIG_FILE is the path to your build configuration file.
  • SERVICE_ACCOUNT is the email associated with your service account. If you don't include this flag, the Cloud Build legacy service account is used if it is available to your project.
  • Optional: --require-approval is the flag to include to configure your trigger to require approval.
  • Optional: --include-logs-with-status is a flag you can specify to show build logs for your repositories. This flag is supported for builds from GitHub and GitHub Enterprise repositories.

For a complete list of flags, see the gcloud reference for how to create triggers for GitHub.

After you run the gcloud command to create a trigger using Cloud Source Repositories or GitHub, you should see an output similar to the following:

  NAME         CREATE_TIME                STATUS
  trigger-001  2019-10-30T20:45:03+00:00

Testing a build trigger

To manually test a build trigger:

  1. Open the Triggers page in the Google Cloud console.

    Open the triggers page

  2. Locate your trigger in the list and then click Run trigger.

Skipping a build trigger

In some cases, you may want to make a change to your source code but you don't want to invoke a build. For example, you might not want to invoke a build when you update documentation or configuration files.

In such scenarios, you can include [skip ci] or [ci skip] in the commit message, and a build will not be invoked.

If you want to run a build on that commit later, use the Run trigger button in the Triggers page.

Including the repository history in a build

To build your source on a Git repository, Cloud Build performs a shallow clone of the repository. This means that only the single commit that started the build is checked out in the workspace to build. Cloud Build does not check out any other branches or history. This is done for efficiency, so that builds don't have to wait to fetch the whole repository and history just to build a single commit.

If you want to include more of your repo's history in the build, add a build step in your build config file to "unshallow" the clone. For example:

steps:
- name: gcr.io/cloud-builders/git
  args: ['fetch', '--unshallow']
...

For more information on git fetch, see git reference. For instructions on writing a build config file, see Build config overview.

Resubmitting a build for approval

If your build has been rejected, you can resubmit your build for approval by following these steps in the Google Cloud console:

  1. Open the Cloud Build History page in the Google Cloud console.

    Open the Cloud Build History page

  2. Click the build ID of the build you'd like to resubmit for approval.

  3. Click Rebuild at the top of the page to resubmit your build for approval.

Your build will start when a user with permissions approves your build. To learn more about Cloud Build approvals, see Gate builds on approval.

Updating a build trigger

Console

  1. Open the Triggers page in the Google Cloud console.

    Open the Build triggers page

  2. Select your project from the project selector drop-down menu at the top of the page.

  3. Click Open.

  4. Locate the row with the trigger you would like to update.

  5. Click the menu (vertical ellipses) located at the right end of the row.

  6. Select Edit.

gcloud

To update a trigger:

  1. Export the trigger you would like to update:

     gcloud beta builds triggers export TRIGGER_NAME --destination=EXPORT_PATH
    

    Where:

    • TRIGGER_NAME is the name of your trigger.
    • EXPORT_PATH is the path you want to export your trigger to. For example, you can specify your path as examples/trigger.yaml. Note that the filename for your trigger should have the .yaml extension.
  2. Open the file containing your exported trigger.

    Your file will look similar to the following:

     createTime: '2022-05-26T21:56:11.830784153Z'
     filename: cloudbuild.yaml
     github:
       name: cloud-build-example
       owner: main
       push:
         branch: master
     id: 86201062-3b14-4b6a-a2fb-4ee924e8b1dd
     # remove field name and value to not show build logs
     includeBuildLogs: INCLUDE_BUILD_LOGS_WITH_STATUS
     name: trigger-001
    
  3. Manually edit your file to update your trigger.

    To view fields you can add or remove from your trigger, see the trigger resource.

  4. Save your file.

  5. Import your trigger:

     gcloud builds triggers import --source=IMPORT_PATH
    

    Where:

    • IMPORT_PATH is the path of your trigger that you would like to import.

Your build trigger is now updated.

Disabling a build trigger

Console

  1. Open the Triggers page in the Google Cloud console.

    Open the Build triggers page

  2. Select your project from the project selector drop-down menu at the top of the page.

  3. Click Open.

  4. Locate the row with the trigger you would like to disable.

  5. Click the menu (vertical ellipses) located at the right end of the row.

  6. Select Disable.

gcloud

To disable a trigger:

  1. Export the trigger you would like to disable:

     gcloud beta builds triggers export TRIGGER_NAME --destination=EXPORT_PATH
    

    Where:

    • TRIGGER_NAME is the name of your trigger.
    • EXPORT_PATH is the path you want to export your trigger to. For example, you can specify your path as examples/trigger.yaml. Note that the filename for your trigger should have the .yaml extension.
  2. Open the file containing your exported trigger.

    Your file will look similar to the following:

     createTime: '2020-02-21T20:02:50.215599013Z'
     description: Push to any branch
     filename: cloudbuild.yaml
     github:
       name: example-repo-name
       owner: example-owner
       push:
         branch: .*
     id: example-id
     name: Push-to-any-branch
     tags:
     - github-default-push-trigger
    
  3. Add the disabled field to the end of your file and set the value to True.

     disabled: True
    
  4. Save your file.

  5. Import your trigger:

     gcloud builds triggers import --source=IMPORT_PATH
    

    Where:

    • IMPORT_PATH is the path of your trigger that you would like to import.

Your build trigger is now disabled.

Disabling a trigger does not delete the trigger. To delete a trigger, see Deleting a build trigger. A trigger can be re-enabled by changing the status to Enabled.

Deleting a build trigger

Console

  1. Open the Triggers page in the Google Cloud console.

    Open the Build triggers page

  2. Select your project from the project selector drop-down menu at the top of the page.

  3. Click Open.

  4. Locate the row with the trigger you would like to delete.

  5. Click the menu (vertical ellipses) located at the right end of the row.

  6. Select Delete.

gcloud

To delete a trigger, run the following command:

  gcloud builds triggers delete TRIGGER_NAME

Where:

  • TRIGGER_NAME is the name of your trigger.

For a complete list of flags, see the gcloud reference for how to delete triggers.

Security implications of build triggers

The service account configured for a build trigger can provide elevated build-time permissions to users who employ triggers to invoke a build. This applies to both your Cloud Build default service account and user-specified service accounts. Keep in mind the following security implications when using build triggers:

  • A user with no access to your Cloud project, but with write access to the repository associated with build triggers in the project will have permissions to change the code being built.
  • If you're using GitHub pull request triggers, any user with read access to the repository can submit a pull request, which may execute a build that includes changes to the code in the pull request. To learn how you can disable this behavior for GitHub pull request triggers, see Creating GitHub triggers.

It's a good security practice to create a service account with only the required roles for your trigger. To learn more see Configure user-specified-service accounts. To learn more about the Cloud Build legacy service account and its associated permissions, see Cloud Build service account.

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