Resolving ModuleNotFoundError in GitHub Workflows for Python Applications

Learn how to fix the `ModuleNotFoundError` in GitHub workflows when running Alembic migrations for your FastAPI application.
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How to Fix ModuleNotFoundError in GitHub Workflows for Your FastAPI Application

As developers, we often face issues integrating different components in our applications, especially when we leverage tools like GitHub Actions for continuous integration. One such common challenge is encountering ModuleNotFoundError while running migrations or tests in GitHub workflows, particularly in Python applications. If you’re configuring workflows for your FastAPI app and running into this problem, you're not alone.

Understanding the Issue

The Setup

In this scenario, you have a FastAPI application where:

When you try to run Alembic migrations in your workflow like this:

[[See Video to Reveal this Text or Code Snippet]]

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The specific line causing the issue is:

[[See Video to Reveal this Text or Code Snippet]]

This error indicates that Python cannot find the module due to how paths are configured in the GitHub Actions environment.

The Solution

To resolve the ModuleNotFoundError, follow these steps:

Step 1: Remove the Path Insertion

[[See Video to Reveal this Text or Code Snippet]]

While this seems like a straightforward method to tweak the module search path, in this case, it complicates the structure unnecessarily and still does not resolve the core issue.

Step 2: Modify Your Workflow Command

Instead, make a simple adjustment to how you run the Alembic commands in your GitHub workflow. Update the command to include the PYTHONPATH environment variable:

[[See Video to Reveal this Text or Code Snippet]]

Why This Works

Conclusion

By following these steps, you should be able to successfully run your migrations without encountering the ModuleNotFoundError. Adjusting how you set the Python path in the GitHub workflow simplifies the process and ensures that your modules are found as expected. If you find yourself facing similar issues in the future, remember to check your paths and manage environment variables effectively!

If you have any other questions or run into further issues with your GitHub workflows or FastAPI application, feel free to reach out for help!