Commit Code Changes Using GitHub Actions

Actions is a super powerful GitHub feature that enables you to execute automated code based on some trigger. It is most often used as a continuous integration tool — to run your test suite when pushing or creating a pull request. I like to think of them as workflows (partially because you put your configuration code in a .github/workflows directory).

Sometimes you may perform some action that changes code and you want that code to be committed back to your repository.

Well, lucky for you, there is a GitHub Action already built to support this: @stefanzweifel/git-auto-commit-action.

Let's say you have an action that simply installs dependencies and runs your test suite with npm run test. The configuration for that workflow may look something like this:

.github/workflows/ci.yml

name: Run CI
on: [push]
jobs:
  Run-All-Tests:
    name: "Run All Tests"
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - name: Install dependencies
        run: npm install
      - name: Run tests
        run: npm run test

Super! That'll run your tests and provide feedback on whether they passed or not (assuming your test suite is configured correctly).

Auto-Committing Changes

Now, suppose npm run test changed some files that you want to commit back to the repository. You can add the git-auto-commit-action at the end of the workflow to commit any changes back to the repository.

Together, it looks like this:

.github/workflows/ci.yml

name: Run CI
on: [push]
jobs:
  Run-All-Tests:
    name: "Run All Tests"
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - name: Install dependencies
        run: npm install
      - name: Run tests
        run: npm run test
      - uses: stefanzweifel/git-auto-commit-action@v4
        with:
          commit_message: "[Bot] Update all the things!"
          commit_user_name: Ian Malcolm
          commit_user_email: ian@example.com
          commit_author: Ian Malcolm <ian@example.com>

Adjusting for Other Triggers

The above code should work just great when using a push trigger. (See here for more info on trigger events.)

But if you want to use this action on anything other than a push event, you will have to store a reference to the current branch.

.github/workflows/ci.yml

name: Run CI
on: [pull_request]
jobs:
  Run-All-Tests:
    name: "Run All Tests"
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
        with:
          ref: $
      - name: Install dependencies
        run: npm install
      - name: Run tests
        run: npm run test
      - uses: stefanzweifel/git-auto-commit-action@v4
        with:
          commit_message: "[Bot] Update all the things!"
          commit_user_name: Ian Malcolm
          commit_user_email: ian@example.com
          commit_author: Ian Malcolm <ian@example.com>

Notice the change here — we added a reference to the actions/checkout action to tell the git-auto-commit-action which branch to push.

Other Gotchas!

There are other items to note when working with this action. They are well-documented. Be sure to first check out the README for this project if you have any issues.