GitHub Classroom Forks Failing: Essential Insights for Internal Template Projects

GitHub Classroom is an invaluable resource for educators, streamlining the process of distributing assignments and managing student repositories. However, even robust platforms can present unexpected challenges. A recent discussion on the GitHub Community forums highlighted a perplexing issue where student repository forks from internal template projects were consistently failing, leading to frustration and lost time.

The Problem: Repositories Created, Then Destroyed

The original poster, hococoder, described a scenario where students accepting an assignment linked to an internal template project would receive messages indicating that their repository was being configured, followed by an error: "something went wrong. We have not received any updates for this assignment. You may want to reaccept the assignment." Crucially, no student repositories were actually created.

Upon examining the logs, hococoder observed a peculiar sequence of events from the GitHub-classroom bot:

- repo.actions_enabled
- repo.create
- integration_installation.repositories_added (here it at least temporarily adds it to the org)
- repository_dependency_graph.enable
- repository_vulnerability_alerts.enable
- repository_security_configuration.applied
- repository_security_configuration.removed
- repo.destroy
- integration_installation.repositories_removed (for GitHub classroom)
- integration_installation.repositories_removed (for GitHub actions)

This log sequence clearly showed the repository being created, undergoing some configuration, and then being immediately destroyed. Interestingly, an empty starter project worked without issues, and when hococoder accepted the assignment as a teacher, the bot successfully added them as an admin and applied security configurations before creating the feedback pull request.

The Core Discovery: Visibility for Internal Templates

Thanks to a student's help in debugging, hococoder uncovered the root cause: students, as outside collaborators, lacked read-only access to the internal starter project. Even though the GitHub Classroom bot itself was performing the fork operation, students needed direct visibility into the template repository for the process to succeed.

As hococoder noted, this requirement isn't explicitly documented and felt counter-intuitive. The workaround involved granting each student read-only access to the starter project, which then allowed the assignment acceptance and repository creation to proceed successfully. This solution, while effective, introduced an additional step: two invites per assignment (one for the starter project, one for their fork), complicating the student onboarding process.

Troubleshooting Tips: Beyond Direct Access

Community member Dagris offered further insights, suggesting that the repo.create followed by repo.destroy pattern is a classic rollback mechanism. This occurs when GitHub Classroom successfully initiates repository creation but then encounters an error during subsequent configuration steps (like adding collaborators or pushing starter code), leading to the deletion of the incomplete repository to prevent a broken state.

Dagris outlined several common causes for this behavior, which can be crucial for anyone using GitHub Classroom:

1. Third-party Application Restrictions: If your Organization has "Third-party application access policy" enabled, ensure that GitHub Classroom has explicit access. Navigate to your Organization's Settings > Third-party access > OAuth application policy and verify GitHub Classroom has a green checkmark or grant access if needed.
2. Template Repository Visibility: While the core issue here was internal visibility, confirming the GitHub Classroom app has permission to read your starter code repository is vital. Temporarily making a private template repository "Public" can help diagnose if permissions are the bottleneck.
3. Re-authorize the App: Sometimes, OAuth tokens can expire or get out of sync. Re-syncing your roster or disconnecting and reconnecting your organization to `classroom.github.com` can refresh the token and resolve underlying authorization issues.

Understanding these log patterns and potential points of failure is a key aspect of effective github monitoring tool usage, allowing educators to quickly diagnose and resolve issues that impact student productivity.

Conclusion

The GitHub Classroom community discussion highlights a critical, albeit undocumented, requirement for internal template projects: students (as outside collaborators) need read-only access to the starter repository for successful assignment acceptance. Beyond this specific fix, the discussion underscores the importance of verifying GitHub Classroom's permissions within your organization and understanding the bot's log sequences as a powerful github monitoring tool for troubleshooting. By proactively addressing these access and authorization settings, educators can ensure a smoother, more productive experience for their students.