Endless cycle of github actions initiated by a build

[iamshreeram]

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I have a repo for which github actions is configured.

1. The action involves code validation and the generation of a PDF file as a result.
2. The GH action then publishes the file to the main branch of a separate repository, all while committing the PDF file to the main branch of the original repository where the action was initiated.
3. Since the commit is made to the same branch, the GH action is triggered once more, causing the cycle to repeat from step 1.

This continuous loop of github actions is persisting. Is there any possible solution? Note: I have not been able to include an if condition to halt the build if the GH action is triggered by a different user, on a different branch, or by a different actor. Nevertheless, the GH action employs my own ID and token to commit the PDF file.

      - name: Get current branch name
        run: echo "BRANCH=${GITHUB_REF#refs/heads/}" >> $GITHUB_ENV
        
      - name: Check if workflow is triggered by the same repository push
        run: |
          if [[ $BRANCH = "main" && ${{ github.actor }} = "your-username" ]]; then
            echo "Skipping workflow run triggered by the same repository."
            exit 0
          fi

      - name: Verify commit author
        run: |
          COMMIT_AUTHOR=$(git --no-pager log -1 --pretty=format:'%an')
          COMMIT_COMMITTER=$(git --no-pager log -1 --pretty=format:'%cn')

          if [[ "$COMMIT_AUTHOR" == "GitHub Actions"* || "$COMMIT_COMMITTER" == "GitHub Actions"* ]]; then
            echo "Commit made by GitHub Actions workflow"
          else
            echo "Commit made by user"
          fi

Is there any other condition to check if the commit is triggered by GH action based on which I can stop the infinite loop ?

[ev1sl]

To prevent a GitHub Actions workflow from triggering itself in an infinite loop, you can use conditional checks within your workflow to determine if the commit was made by a GitHub Actions bot or by another user. If the commit was made by the bot, you can skip the rest of the job.

Here is a common approach using the GITHUB_ACTOR and github.event contexts:

jobs:
  build:
    runs-on: ubuntu-latest
    if: ${{ github.actor != 'github-actions[bot]' && github.event_name != 'push' || github.event.pusher.name != 'github-actions[bot]' }}
    steps:
      - name: Checkout code
        uses: actions/checkout@v2

      # Your other steps...

In this example:

github.actor provides the name of the person or app that initiated the workflow. If this is 'github-actions[bot]', then it means the workflow was triggered by GitHub Actions.
github.event_name checks the type of event that triggered the workflow. If it's a 'push' event, you can further check who the pusher was.
github.event.pusher.name can check the name of the user who pushed.
You've mentioned that you're using your own ID and token to commit the PDF file, which means the actor for the commit will be your username, not 'github-actions[bot]'. In this case, you need to use a different method, such as checking for a specific commit message that you set when the action commits the PDF file.

Here's an example of how you can skip a job if the last commit message contains a specific keyword (like [skip ci] or some unique identifier):

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v2

      - name: Check last commit message
        id: commit-message
        run: echo "COMMIT_MESSAGE=$(git log -1 --pretty=format:'%s')" >> $GITHUB_ENV

      - name: Skip if commit is automated
        if: contains(env.COMMIT_MESSAGE, '[skip ci]')
        run: |
          echo "Automated commit detected - skipping job"
          exit 0

  # Your other steps...

In this setup:

The first step is to extract the last commit message and store it in an environment variable.
The second step uses an if condition to check if the commit message contains the [skip ci] keyword.
If the keyword is present, the step will print a message and then call exit 0, which successfully ends the current job without failing the workflow.
You would need to make sure that when the GitHub Action commits the PDF file, it includes this specific keyword in the commit message.

[iamshreeram]

@ev1sl , thanks. that works!

[suzaku]

I tried to reproduce a dead loop like this but failed: https://github.com/suzaku/github-actor-playground/blob/main/.github/workflows/blank.yml#L32-L37
The push that happened inside the action seems to be ignored: https://github.com/suzaku/github-actor-playground/actions
Any idea what's different?

[assignUser]

publishes the file to the main branch of a separate repository

This means they are using a PAT and not the built in GITHUB_TOKEN but you are using the default token which explicitly does not trigger CI events when used for pushing (to prevent endless loops ^^) https://docs.github.com/en/actions/security-guides/automatic-token-authentication#using-the-github_token-in-a-workflow

[Khalilheyrani6367]

Thank you GITHUb 🙏