refactor: remove BullMQ task scheduling system

[mchestr]

Summary

• Remove broken BullMQ-based task scheduling functionality
• Preserve Discord bot feature for marking media as finished
• Clean up related dependencies (bullmq, ioredis)

Changes Made

• Deleted core files: lib/maintenance/queue.ts, worker.ts, scheduler.ts
• Removed API route: /api/admin/maintenance/schedulers
• Updated actions: Removed triggerManualScan and triggerDeletion operations
• Updated rules.ts: Removed scheduler sync calls from CRUD operations
• Updated UI: Removed scan button from RuleList component
• Cleaned up config: Removed Redis configuration from example.env
• Removed dependencies: bullmq, ioredis, @types/ioredis

What Still Works

• Maintenance rule CRUD operations (create, read, update, delete, toggle)
• User media marks (Discord bot can still mark media as finished)
• All other maintenance-related features

What Needs Redesign

• Manual scan triggering
• Deletion job execution
• Scheduled maintenance rule execution

The task scheduling system was broken and needs to be rethought. This PR removes the broken implementation to clean up the codebase.

Test plan

• All maintenance-related unit tests pass (631 tests)
• Dependencies removed from package.json
• Manual verification of maintenance rules page
• Verify Discord bot media marking still works

🤖 Generated with Claude Code

[claude]

PR Review: Remove BullMQ Task Scheduling System

Summary

This PR successfully removes the BullMQ-based task scheduling infrastructure and its dependencies (bullmq, ioredis) from the codebase. The changes are clean, well-tested, and appropriately scoped.

✅ Strengths

1. Thorough Cleanup

• All queue-related code properly removed (queue.ts, worker.ts, scheduler.ts)
• Dependencies cleanly removed from package.json (bullmq, ioredis, @types/ioredis)
• Test files for removed functionality deleted (226 + 203 + 322 + 320 lines of tests)
• API route /api/admin/maintenance/schedulers removed
• Redis configuration removed from example.env
• instrumentation.ts file removed

2. Excellent Test Coverage

• All 631 maintenance-related unit tests still pass
• Comprehensive test removal ensures no orphaned test code
• No lingering references to removed functions found in codebase

3. Clear Documentation

• Well-written PR description explaining what was removed and what remains
• TODO comments added in code indicating functionality needs redesign
• Comments in actions/maintenance/index.ts and operations.ts clearly state the removal

4. Clean Code Patterns

• Proper use of export {} in operations.ts to maintain valid TypeScript module
• UI components properly updated (RuleList removed scan button and related props)
• Server actions updated to remove queue operations
• Proper removal of scheduler sync calls from CRUD operations

5. Preserves Core Functionality

• Maintenance rule CRUD operations intact
• User media marks (Discord bot feature) preserved
• All other maintenance features still functional

🔍 Code Quality Observations

Well-Handled Edge Cases

1. Lazy-loaded queue imports removed: Previous code used dynamic imports to avoid Redis connection on module load - properly cleaned up
2. Error handling removed appropriately: Schedule sync errors that were logged but not thrown are gone
3. Component props cleaned: RuleList interface properly updated (removed onManualScan, isScanPending)
4. Page-level mutation removed: rules/page.tsx properly removes scanMutation and related handlers

TypeScript Safety

• ✅ No type errors introduced (operations.ts uses proper export {} pattern)
• ✅ Function exports properly removed from index.ts
• ✅ No lingering imports to deleted modules

⚠️ Considerations & Recommendations

1. Export Pattern in operations.ts

Current state:

// This file previously contained queue-based operations...
export {}

Recommendation: Consider one of these alternatives for better developer experience:

• Option A: Delete operations.ts entirely and update imports in index.ts
• Option B: Add placeholder functions that throw descriptive errors:

export async function triggerManualScan() {
  throw new Error('Manual scan functionality removed. Awaiting redesign without BullMQ.')
}

Rationale: The current export {} approach is valid but could be confusing for developers. If someone tries to import the old functions, they'll get a TypeScript error that doesn't explain why they're missing.

2. Remaining Scanner Code

Observation: The PR removes queue/scheduler/worker but keeps lib/maintenance/scanner.ts and lib/maintenance/deleter.ts.

Question: How will these be invoked now?

• scanner.ts appears to have the logic to identify candidates
• deleter.ts appears to handle deletion operations
• Without the queue system, what's the new execution model?

Recommendation: Document in the TODO or CLAUDE.md how these modules will be re-integrated when the redesign happens.

3. User Communication

Observation: The UI removes the manual scan button, but users may not know why it's gone.

Recommendation: Consider adding a temporary UI message in the maintenance rules page:

<div className="bg-yellow-900/20 border border-yellow-500/30 rounded-lg p-4 mb-4">
  <p className="text-sm text-yellow-200">
    Manual scan functionality is temporarily unavailable while we redesign the task system.
  </p>
</div>

4. Migration Path for Existing Data

Question: Are there any existing:

• Scheduled jobs in Redis that need cleanup?
• Database records referencing job IDs?
• Incomplete scans that should be marked as failed/cancelled?

Recommendation: If users have running instances, provide migration guidance in the PR description or deployment notes.

🔒 Security Review

✅ No security concerns identified:

• No new external data handling
• No changes to authentication/authorization
• Dependencies removed (reduced attack surface)
• No sensitive data exposure

🚀 Performance Considerations

✅ Positive impact:

• Reduced dependencies (smaller bundle, fewer security vulnerabilities)
• No Redis connection overhead for systems not using the feature
• Removed lazy-loading complexity

📋 Test Plan Completion

• All maintenance-related unit tests pass (631 tests) ✅
• Dependencies removed from package.json ✅
• Manual verification of maintenance rules page ⏳
• Verify Discord bot media marking still works ⏳

Recommendation: Complete the unchecked test plan items before merging.

🎯 Final Verdict

APPROVE with minor suggestions

This is a well-executed cleanup PR that:

• Removes broken functionality cleanly
• Maintains test coverage
• Preserves working features
• Documents what needs to be redesigned

The suggestions above are minor improvements to developer experience and user communication, not blockers.

Before Merging:

1. ✅ Verify all tests pass
2. ⏳ Complete manual testing (maintenance rules page, Discord bot)
3. 🤔 Consider: Delete or add error-throwing placeholders in operations.ts
4. 🤔 Consider: Add temporary UI message about missing manual scan feature
5. 📝 Document scanner/deleter re-integration plan

Great work on the cleanup! The -2211 lines of code removal is substantial and makes the codebase more maintainable. 🎉

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Review generated by Claude Code following CLAUDE.md conventions