GitHub Action to skip CI in PR

Do not use this anymore

See https://github.blog/changelog/2021-02-08-github-actions-skip-pull-request-and-push-workflows-with-skip-ci/ .

Introduction

Check if the latest commit message in the pull request contains one of these directives (case-insensitive):

[skip ci]
[ci skip]
[skip action]
[action skip]
[skip actions]
[actions skip]

If it does, the job running this action will fail, thus preventing downstream jobs or steps from running. Otherwise, jobs will run as usual.

Non-pull request event will not be affected. This is because we want the CI to run when a PR is merged even though its last commit has a directive to skip CI for that PR.

Ways to customize

The behavior described above is the default, but it could be customized using these options (also see examples below):

SKIP_DIRECTIVES (comma-separated strings) to define your own directives to skip a job or workflow. This will overwrite the default directives.
NO_FAIL (boolean, set this to true) to prevent this action from failing. Instead, it would set an output value for run_next to true or false to be used by downstream jobs.

Examples

Here are some simple examples to use this action in your workflows.

This fails check_skip_ci, thus preventing tests from running. It is the simplest way to use this action:

name: CI

on:
  push:
  pull_request:

jobs:
  # This action should be a job before you run your tests.
  check_skip_ci:
    name: Skip CI
    runs-on: ubuntu-latest
    steps:
    - name: Fail means CI is skipped on purpose
      uses: OpenAstronomy/action-skip-ci@main
      with:
        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

  # This is placeholder for your real tests.
  tests:
    name: Run tests
    needs: check_skip_ci
    ...

This makes check_skip_ci sets an output instead of failing. It is more elegant (no red "x" in your check status) but requires knowledge on how to pass output to downstream jobs. This example also illustrates how to set custom directives, though they are not required if you are happy with the default directives:

name: CI

on:
  push:
  pull_request:

jobs:
  # This action should be a job before you run your tests.
  check_skip_ci:
    name: Skip CI
    runs-on: ubuntu-latest
    outputs:
      run_next: ${{ steps.skip_ci_step.outputs.run_next }}
    steps:
    - name: Set output to skip CI
      uses: OpenAstronomy/action-skip-ci@main
      id: skip_ci_step
      with:
        NO_FAIL: true
        SKIP_DIRECTIVES: '[skip other],[other skip]'
        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

  # This is placeholder for your real tests.
  tests:
    name: Run tests
    needs: check_skip_ci
    if: needs.check_skip_ci.outputs.run_next == 'true'
    ...

Why does this action not cancel workflow instead of failing?

This is because cancelling the workflow does not work when the command is issued from a pull request opened from a fork due to lack of write access from the fork's GitHub token. The cancellation does not fail but nothing gets cancelled anyway.

For developers

To install/update dependencies:

npm install

To build:

npm run build

To run it locally (might require tinkering with src/main.ts to mock the GitHub events):

node dist/index.js