Understanding and Troubleshooting GitHub Actions Permissions for Automated File Updates

If you’re developing an automated workflow on GitHub Actions to scrape data and update files within your repository, encountering permission issues can be frustrating—especially if you’re new to web development or automation. Recently, many developers have faced a common challenge: attempts to commit changes via GitHub Actions fail due to insufficient access rights, typically returning a 403 error.

In this post, we’ll explore the typical scenario where a GitHub Actions workflow successfully scrapes data and modifies files but fails during the commit stage, citing permission problems. We’ll also provide practical insights on how to troubleshoot and resolve this issue effectively.

The Scenario

Suppose you’ve set up a GitHub Actions workflow designed to:

1. Extract information from an external calendar.
2. Store the retrieved data in a JSON file within your repository.
3. Update the JSON file automatically whenever new data is fetched.

This approach is cost-effective, as it leverages GitHub’s free CI/CD platform. The workflow automates scraping and updates seamlessly, but trouble arises at the commit step.

The Issue

While the scraping and file updating seem to proceed correctly, the commit operation fails with an error message similar to:

plaintext
remote: Permission to [repository] denied to github-actions[bot].
fatal: unable to access '[repository URL]': The requested URL returned error: 403
Error: Process completed with exit code 128.

This indicates that the workflow doesn’t have sufficient permissions to push changes back to your repository.

Common Causes and Solutions

1. Incorrect or Missing Access Token

GitHub Actions relies on tokens, such as GITHUB_TOKEN, to authenticate. Ensure that you’re using the default GITHUB_TOKEN or a Personal Access Token (PAT) with appropriate scopes (repo for private repositories).

Solution:
– Use the built-in GITHUB_TOKEN provided by GitHub in your workflow. It automatically has permissions to make API calls, including pushes, unless restricted.
– Verify in your workflow YAML that you are referencing secrets.GITHUB_TOKEN, e.g.:

“`yaml
– name: Commit changes
run: |
git config –global user.name “github-actions[bot]”
git config –global user.email “github-actions[bot]@users.noreply.github.com”
git add filename.json
git commit -m “Update JSON with latest data”
git push origin main
env: