Automatic token authentication

About the GITHUB_TOKEN secret

At the start of each workflow run, GitHub automatically creates a unique GITHUB_TOKEN secret to use in your workflow. You can use the GITHUB_TOKEN to authenticate in a workflow run.

When you enable GitHub Actions, GitHub installs a GitHub App on your repository. The GITHUB_TOKEN secret is a GitHub App installation access token. You can use the installation access token to authenticate on behalf of the GitHub App installed on your repository. The token's permissions are limited to the repository that contains your workflow. For more information, see "Permissions for the GITHUB_TOKEN."

Before each job begins, GitHub fetches an installation access token for the job. O GITHUB_TOKEN expira quando um trabalho é concluído ou após, no máximo, 24 horas.

The token is also available in the github.token context. For more information, see "Contexts."

Using the GITHUB_TOKEN in a workflow

You can use the GITHUB_TOKEN by using the standard syntax for referencing secrets: ${{ secrets.GITHUB_TOKEN }}. Examples of using the GITHUB_TOKEN include passing the token as an input to an action, or using it to make an authenticated GitHub Enterprise Server API request.

When you use the repository's GITHUB_TOKEN to perform tasks, events triggered by the GITHUB_TOKEN will not create a new workflow run. This prevents you from accidentally creating recursive workflow runs. For example, if a workflow run pushes code using the repository's GITHUB_TOKEN, a new workflow will not run even when the repository contains a workflow configured to run when push events occur.

Example 1: passing the GITHUB_TOKEN as an input

Este exemplo de fluxo de trabalho usa a ação do rotulador, que requer o GITHUB_TOKEN como o valor para o parâmetro de entrada repo-token:

name: Pull request labeler
on: [ pull_request_target ]

permissions:
  contents: read
  pull-requests: write

jobs:
  triage:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/labeler@v3
        with:
          repo-token: ${{ secrets.GITHUB_TOKEN }}

Example 2: calling the REST API

You can use the GITHUB_TOKEN to make authenticated API calls. This example workflow creates an issue using the GitHub REST API:

name: Create issue on commit

on: [ push ]

jobs:
  create_issue:
    runs-on: ubuntu-latest
    permissions:
      issues: write 
    steps:
      - name: Create issue using REST API
        run: |
          curl --request POST \
          --url http(s)://[hostname]/api/v3/repos/${{ github.repository }}/issues \
          --header 'authorization: Bearer ${{ secrets.GITHUB_TOKEN }}' \
          --header 'content-type: application/json' \
          --data '{
            "title": "Automated issue for commit: ${{ github.sha }}",
            "body": "This issue was automatically created by the GitHub Action workflow **${{ github.workflow }}**. \n\n The commit hash was: _${{ github.sha }}_."
            }' \
          --fail

Permissions for the GITHUB_TOKEN

For information about the API endpoints GitHub Apps can access with each permission, see "GitHub App Permissions."

The following table shows the permissions granted to the GITHUB_TOKEN by default. People with admin permissions to an organization or repository can set the default permissions to be either permissive or restricted. For information on how to set the default permissions for the GITHUB_TOKEN for your enterprise, organization, or repository, see "Enforcing policies for GitHub Actions in your enterprise," "Disabling or limiting GitHub Actions for your organization," or "Managing GitHub Actions settings for a repository."

Modifying the permissions for the GITHUB_TOKEN

You can modify the permissions for the GITHUB_TOKEN in individual workflow files. If the default permissions for the GITHUB_TOKEN are restrictive, you may have to elevate the permissions to allow some actions and commands to run successfully. If the default permissions are permissive, you can edit the workflow file to remove some permissions from the GITHUB_TOKEN. As a good security practice, you should grant the GITHUB_TOKEN the least required access.

You can see the permissions that GITHUB_TOKEN had for a specific job in the "Set up job" section of the workflow run log. For more information, see "Using workflow run logs."

You can use the permissions key in your workflow file to modify permissions for the GITHUB_TOKEN for an entire workflow or for individual jobs. This allows you to configure the minimum required permissions for a workflow or job. When the permissions key is used, all unspecified permissions are set to no access, with the exception of the metadata scope, which always gets read access.

Além disso, você pode usar a chave permissions para adicionar e remover permissões de leitura para repositórios com fork, mas normalmente não pode permitir acesso de gravação. A exceção desse comportamento é quando um usuário administrador selecionou a opção Enviar tokens para fluxos de trabalho de solicitações de pull nas configurações do GitHub Actions. Para obter mais informações, confira "Como gerenciar as configurações do GitHub Actions de um repositório".

The two workflow examples earlier in this article show the permissions key being used at the workflow level, and at the job level. In Example 1 the two permissions are specified for the entire workflow. In Example 2 write access is granted for one scope for a single job.

For full details of the permissions key, see "Workflow syntax for GitHub Actions."

How the permissions are calculated for a workflow job

The permissions for the GITHUB_TOKEN are initially set to the default setting for the enterprise, organization, or repository. If the default is set to the restricted permissions at any of these levels then this will apply to the relevant repositories. For example, if you choose the restricted default at the organization level then all repositories in that organization will use the restricted permissions as the default. The permissions are then adjusted based on any configuration within the workflow file, first at the workflow level and then at the job level. Finally, if the workflow was triggered by a pull request from a forked repository, and the Send write tokens to workflows from pull requests setting is not selected, the permissions are adjusted to change any write permissions to read only.

Granting additional permissions

If you need a token that requires permissions that aren't available in the GITHUB_TOKEN, you can create a personal access token and set it as a secret in your repository:

1. Use or create a token with the appropriate permissions for that repository. For more information, see "Creating a personal access token."
2. Add the token as a secret in your workflow's repository, and refer to it using the ${{ secrets.SECRET_NAME }} syntax. For more information, see "Creating and using encrypted secrets."

Further reading

• "Resources in the REST API"