Troubleshooting Dependabot on GitHub Actions

Restrictions when Dependabot triggers events

Dependabot is able to trigger GitHub Actions workflows on its pull requests and comments; however, certain events are treated differently.

For workflows initiated by Dependabot (github.actor == 'dependabot[bot]') using the pull_request, pull_request_review, pull_request_review_comment, push, create, deployment, and deployment_status events, these restrictions apply:

• GITHUB_TOKEN has read-only permissions by default.
• Secrets are populated from Dependabot secrets. GitHub Actions secrets are not available.

For workflows initiated by Dependabot (github.actor == 'dependabot[bot]') using the pull_request_target event, if the base ref of the pull request was created by Dependabot (github.event.pull_request.user.login == 'dependabot[bot]'), the GITHUB_TOKEN will be read-only and secrets are not available.

These restrictions apply even if the workflow is re-run by a different actor.

For more information, see Keeping your GitHub Actions and workflows secure: Preventing pwn requests.

Troubleshooting failures when Dependabot triggers existing workflows

Después de configurar las actualizaciones del Dependabot para tu instancia de GitHub Enterprise Server, puedes ver errores cuando los flujos de trabajo existentes los desencadenan los eventos del Dependabot.

De manera predeterminada, las ejecuciones de flujo de trabajo de GitHub Actions que se activan desde Dependabot a partir de los eventos push, pull_request, pull_request_review o pull_request_review_comment se tratan como si se abrieran desde una bifurcación de repositorio. A diferencia de los flujos de trabajo que activan otros actores, esto significa que recibieron un GITHUB_TOKEN de solo lectura y no tienen acceso a ninguno de los secretos que normalmente se encuentran disponibles. Esto ocasionará que cualquier flujo de trabajo que intente escribir en el repositorio falle cuando los activa el Dependabot.

Hay tres formas de resolver este problema:

1. Puede actualizar los flujos de trabajo para que ya nos los active Dependabot mediante una expresión como: if: github.actor != 'dependabot[bot]'. Para obtener más información, vea «Evaluación de expresiones en flujos de trabajo y acciones».
2. Puede modificar los flujos de trabajo para usar un proceso en dos pasos que incluya pull_request_target, que no tiene estas limitaciones. Para obtener más información, vea «Automatizar al Dependabot con las GitHub Actions».
3. Puede proporcionar acceso a los flujos de trabajo que activa Dependabot a secretos y permitir que el término permissions aumente el alcance predeterminado de GITHUB_TOKEN.

Some troubleshooting advice is provided in this article. You can also see Sintaxis del flujo de trabajo para Acciones de GitHub.

Accessing secrets

When a Dependabot event triggers a workflow, the only secrets available to the workflow are Dependabot secrets. GitHub Actions secrets are not available. You must therefore store any secrets that are used by a workflow triggered by Dependabot events as Dependabot secrets. For more information, see Configuración del acceso a registros privados para Dependabot.

Dependabot secrets are added to the secrets context and referenced using exactly the same syntax as secrets for GitHub Actions. For more information, see Uso de secretos en Acciones de GitHub.

If you have a workflow that will be triggered by Dependabot and also by other actors, the simplest solution is to store the token with the permissions required in an action and in a Dependabot secret with identical names. Then the workflow can include a single call to these secrets. If the secret for Dependabot has a different name, use conditions to specify the correct secrets for different actors to use.

For examples that use conditions, see Automatizar al Dependabot con las GitHub Actions.

To access a private container registry on AWS with a user name and password, a workflow must include a secret for username and password.

In this example, when Dependabot triggers the workflow, the Dependabot secrets with the names READONLY_AWS_ACCESS_KEY_ID and READONLY_AWS_ACCESS_KEY are used. If another actor triggers the workflow, the actions secrets with those names are used.

name: CI
on:
  pull_request:
    branches: [ main ]

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

      - name: Login to private container registry for dependencies
        uses: docker/login-action@3b4c5d6e7f8a9b0c1d2e3f4a5b6c7d8e9f0a1b2c
        with:
          registry: https://1234567890.dkr.ecr.us-east-1.amazonaws.com
          username: ${{ secrets.READONLY_AWS_ACCESS_KEY_ID }}
          password: ${{ secrets.READONLY_AWS_ACCESS_KEY }}

      - name: Build the Docker image
        run: docker build . --file Dockerfile --tag my-image-name:$(date +%s)

name: CI
on:
  pull_request:
    branches: [ main ]

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

      - name: Login to private container registry for dependencies
        uses: docker/login-action@3b4c5d6e7f8a9b0c1d2e3f4a5b6c7d8e9f0a1b2c
        with:
          registry: https://1234567890.dkr.ecr.us-east-1.amazonaws.com
          username: ${{ secrets.READONLY_AWS_ACCESS_KEY_ID }}
          password: ${{ secrets.READONLY_AWS_ACCESS_KEY }}

      - name: Build the Docker image
        run: docker build . --file Dockerfile --tag my-image-name:$(date +%s)

Changing GITHUB_TOKEN permissions

By default, GitHub Actions workflows triggered by Dependabot get a GITHUB_TOKEN with read-only permissions. You can use the permissions key in your workflow to increase the access for the token:

name: CI
on: pull_request

# Set the access for individual scopes, or use permissions: write-all
permissions:
  pull-requests: write
  issues: write
  repository-projects: write
  ...

jobs:
  ...

name: CI
on: pull_request

# Set the access for individual scopes, or use permissions: write-all
permissions:
  pull-requests: write
  issues: write
  repository-projects: write
  ...

jobs:
  ...

For more information, see Autenticación automática de tokens.

Manually re-running a workflow

When you manually re-run a Dependabot workflow, it will run with the same privileges as before even if the user who initiated the rerun has different privileges. For more information, see Volver a ejecutar flujos de trabajo y jobs.