actions/github-script

This action makes it easy to quickly write a script in your workflow that uses the GitHub API and the workflow run context.

To use this action, provide an input named script that contains the body of an asynchronous function call. The following arguments will be provided:

github A pre-authenticated octokit/rest.js client with pagination plugins
context An object containing the context of the workflow run
core A reference to the @actions/core package
glob A reference to the @actions/glob package
io A reference to the @actions/io package
exec A reference to the @actions/exec package
require A proxy wrapper around the normal Node.js require to enable requiring relative paths (relative to the current working directory) and requiring npm packages installed in the current working directory. If for some reason you need the non-wrapped require, there is an escape hatch available: __original_require__ is the original value of require without our wrapping applied.

Since the script is just a function body, these values will already be defined, so you don't have to import them (see examples below).

See octokit/rest.js for the API client documentation.

Breaking Changes

Breaking changes in V6

Version 6 of this action updated the runtime to Node 16 - https://docs.github.com/en/actions/creating-actions/metadata-syntax-for-github-actions#example-using-nodejs-v16

All scripts are now run with Node 16 instead of Node 12 and are affected by any breaking changes between Node 12 and 16.

Breaking changes in V5

Version 5 of this action includes the version 5 of @actions/github and @octokit/plugin-rest-endpoint-methods. As part of this update, the Octokit context available via github no longer has REST methods directly. These methods are available via github.rest.* - https://github.com/octokit/plugin-rest-endpoint-methods.js/releases/tag/v5.0.0

For example, github.issues.createComment in V4 becomes github.rest.issues.createComment in V5

github.request, github.paginate, and github.graphql are unchanged.

Development

See development.md.

Reading step results

The return value of the script will be in the step's outputs under the "result" key.

- uses: actions/github-script@v6
  id: set-result
  with:
    script: return "Hello!"
    result-encoding: string
- name: Get result
  run: echo "${{steps.set-result.outputs.result}}"

See "Result encoding" for details on how the encoding of these outputs can be changed.

Result encoding

By default, the JSON-encoded return value of the function is set as the "result" in the output of a github-script step. For some workflows, string encoding is preferred. This option can be set using the result-encoding input:

- uses: actions/github-script@v6
  id: my-script
  with:
    result-encoding: string
    script: return "I will be string (not JSON) encoded!"

Retries

By default, requests made with the github instance will not be retried. You can configure this with the retries option:

- uses: actions/github-script@v6
  id: my-script
  with:
    result-encoding: string
    retries: 3
    script: |
      github.rest.issues.get({
        issue_number: context.issue.number,
        owner: context.repo.owner,
        repo: context.repo.repo,
      })

In this example, request failures from github.rest.issues.get() will be retried up to 3 times.

You can also configure which status codes should be exempt from retries via the retry-exempt-status-codes option:

- uses: actions/github-script@v6
  id: my-script
  with:
    result-encoding: string
    retries: 3
    retry-exempt-status-codes: 400,401
    script: |
      github.rest.issues.get({
        issue_number: context.issue.number,
        owner: context.repo.owner,
        repo: context.repo.repo,
      })

By default, the following status codes will not be retried: 400, 401, 403, 404, 422 (source).

These retries are implemented using the octokit/plugin-retry.js plugin. The retries use exponential backoff to space out retries. (source)

Examples

Note that github-token is optional in this action, and the input is there in case you need to use a non-default token.

By default, github-script will use the token provided to your workflow.

Print the available attributes of context

- name: View context attributes
  uses: actions/github-script@v6
  with:
    script: console.log(context)

Comment on an issue

on:
  issues:
    types: [opened]

jobs:
  comment:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/github-script@v6
        with:
          script: |
            github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: '👋 Thanks for reporting!'
            })

Apply a label to an issue

on:
  issues:
    types: [opened]

jobs:
  apply-label:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/github-script@v6
        with:
          script: |
            github.rest.issues.addLabels({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              labels: ['Triage']
            })

Welcome a first-time contributor

You can format text in comments using the same Markdown syntax as the GitHub web interface:

on: pull_request_target

jobs:
  welcome:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/github-script@v6
        with:
          script: |
            // Get a list of all issues created by the PR opener
            // See: https://octokit.github.io/rest.js/#pagination
            const creator = context.payload.sender.login
            const opts = github.rest.issues.listForRepo.endpoint.merge({
              ...context.issue,
              creator,
              state: 'all'
            })
            const issues = await github.paginate(opts)

            for (const issue of issues) {
              if (issue.number === context.issue.number) {
                continue
              }

              if (issue.pull_request) {
                return // Creator is already a contributor.
              }
            }

            await github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: `**Welcome**, new contributor!

                Please make sure you're read our [contributing guide](CONTRIBUTING.md) and we look forward to reviewing your Pull request shortly ✨`
            })

Download data from a URL

You can use the github object to access the Octokit API. For instance, github.request

on: pull_request

jobs:
  diff:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/github-script@v6
        with:
          script: |
            const diff_url = context.payload.pull_request.diff_url
            const result = await github.request(diff_url)
            console.log(result)

(Note that this particular example only works for a public URL, where the diff URL is publicly accessible. Getting the diff for a private URL requires using the API.)

This will print the full diff object in the screen; result.data will contain the actual diff text.

Run custom GraphQL queries

You can use the github.graphql object to run custom GraphQL queries against the GitHub API.

jobs:
  list-issues:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/github-script@v6
        with:
          script: |
            const query = `query($owner:String!, $name:String!, $label:String!) {
              repository(owner:$owner, name:$name){
                issues(first:100, labels: [$label]) {
                  nodes {
                    id
                  }
                }
              }
            }`;
            const variables = {
              owner: context.repo.owner,
              name: context.repo.repo,
              label: 'wontfix'
            }
            const result = await github.graphql(query, variables)
            console.log(result)

Run a separate file

If you don't want to inline your entire script that you want to run, you can use a separate JavaScript module in your repository like so:

on: push

jobs:
  echo-input:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: actions/github-script@v6
        with:
          script: |
            const script = require('./path/to/script.js')
            console.log(script({github, context}))

And then export a function from your module:

module.exports = ({github, context}) => {
  return context.payload.client_payload.value
}

Note that because you can't require things like the GitHub context or Actions Toolkit libraries, you'll want to pass them as arguments to your external function.

Additionally, you'll want to use the checkout action to make sure your script file is available.

Run a separate file with an async function

You can also use async functions in this manner, as long as you await it in the inline script.

In your workflow:

on: push

jobs:
  echo-input:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: actions/github-script@v6
        env:
          SHA: '${{env.parentSHA}}'
        with:
          script: |
            const script = require('./path/to/script.js')
            await script({github, context, core})

And then export an async function from your module:

module.exports = async ({github, context, core}) => {
  const {SHA} = process.env
  const commit = await github.rest.repos.getCommit({
    owner: context.repo.owner,
    repo: context.repo.repo,
    ref: `${SHA}`
  })
  core.exportVariable('author', commit.data.commit.author.email)
}

Use npm packages

Like importing your own files above, you can also use installed modules. Note that this is achieved with a wrapper on top require, so if you're trying to require a module inside your own file, you might need to import it externally or pass the require wrapper to your file:

on: push

jobs:
  echo-input:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: actions/setup-node@v2
        with:
          node-version: 14
      - run: npm ci
      # or one-off:
      - run: npm install execa
      - uses: actions/github-script@v6
        with:
          script: |
            const execa = require('execa')

            const { stdout } = await execa('echo', ['hello', 'world'])

            console.log(stdout)

Use ESM `import`

To import an ESM file, you'll need to reference your script by an absolute path and ensure you have a package.json file with "type": "module" specified.

For a script in your repository src/print-stuff.js:

export default function printStuff() {
  console.log('stuff')
}

on: push

jobs:
  print-stuff:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: actions/github-script@v6
        with:
          script: |
            const { default: printStuff } = await import('${{ github.workspace }}/src/print-stuff.js')

            await printStuff()

Use env as input

You can set env vars to use them in your script:

on: push

jobs:
  echo-input:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/github-script@v6
        env:
          FIRST_NAME: Mona
          LAST_NAME: Octocat
        with:
          script: |
            const { FIRST_NAME, LAST_NAME } = process.env

            console.log(`Hello ${FIRST_NAME} ${LAST_NAME}`)

Using a separate GitHub token

The GITHUB_TOKEN used by default is scoped to the current repository, see Authentication in a workflow.

If you need access to a different repository or an API that the GITHUB_TOKEN doesn't have permissions to, you can provide your own PAT as a secret using the github-token input.

Learn more about creating and using encrypted secrets

on:
  issues:
    types: [opened]

jobs:
  apply-label:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/github-script@v6
        with:
          github-token: ${{ secrets.MY_PAT }}
          script: |
            github.rest.issues.addLabels({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              labels: ['Triage']
            })

jlosito/github-script