yellowjacket/.planning/phases/11-per-library-scan-pipeline/11-01-SUMMARY.md

phase, plan, subsystem, tags, requires, provides, affects, tech-stack, key-files, key-decisions, patterns-established, requirements-completed, duration, completed

phase	plan	subsystem	tags	requires	provides	affects	tech-stack	key-files	key-decisions	patterns-established	requirements-completed	duration	completed
11-per-library-scan-pipeline	01	library	scan-queue per-library wails-bindings sqlc events	phase provides 10-schema-migration libraries table, library_id column on audio_files, GetLibrary/GetAllLibraries/GetLibraryByPath queries	ScanLibrary(id) Wails-bound method for per-library scanning ScanAllLibraries() Wails-bound method for bulk sequential scanning Scan queue coordinator with FIFO sequential execution and silent dedup CancelCurrentScan() and CancelAllScans() for queue-aware cancellation GetScanQueueLength() and QueuedLibraryNames() for UI display Library-aware ScanProgress and ScanMetrics with libraryId, libraryName, queuedCount LibraryScanQueued and LibraryScanQueueDrained events CreateAudioFile with library_id parameter	12-library-crud-data-integrity 13-library-views-phantom-tracks	added patterns Scan queue coordinator pattern: FIFO queue with single-active-scan mutex scanInternal() as reusable per-library scan engine Silent dedup for scan requests (no-op if already scanning or queued)	created modified backend/library/scan_queue.go backend/library/library.go backend/library/scan_control.go backend/library/metrics.go backend/events/events.go backend/database/sql/queries/audio_files.sql backend/database/sql/sqlcgen/audio_files.sql.go frontend/src/events.ts frontend/wailsjs/go/library/Library.d.ts frontend/wailsjs/go/library/Library.js	Library identification threaded through importResult.libraryID rather than adding field to Library struct scanInternal returns *ScanMetrics instead of (*ScanMetrics, error) — errors are logged and warnings accumulated Worker count auto-detected per library path (ScanConcurrencyAuto) rather than using global config value Backward-compatible Scan() retained as deprecated wrapper for handleConfigUpdate	Scan queue coordinator: scanQueue []scanQueueEntry + drainQueue() pattern for sequential execution mkProgress closure for DRY ScanProgress event construction with library identification	LSCAN-01 LSCAN-02 LSCAN-04	7min	2026-03-09

Phase 11 Plan 01: Per-Library Scan Pipeline Summary

ScanLibrary(id) with FIFO queue coordinator, per-library file association via library_id, and queue-aware cancel/pause controls

Performance

• Duration: 7 min
• Started: 2026-03-09T19:56:10Z
• Completed: 2026-03-09T20:03:14Z
• Tasks: 2
• Files modified: 11

Accomplishments

• ScanLibrary(id) resolves library path from DB and scans only that directory, associating files with library_id
• FIFO scan queue ensures only one scan runs at a time, with silent dedup for duplicate requests
• ScanAllLibraries() queries all libraries and queues them sequentially
• CancelCurrentScan() stops current library and auto-starts next queued; CancelAllScans() clears queue too
• Pause freezes current scan AND queue (drainQueue only runs on scan completion)
• All scan events (progress, started, complete, cancelled) include library name and queue count

Task Commits

Each task was committed atomically (note: lint fix amend merged both into single commit):

1. Task 1: Add library_id to CreateAudioFile + update events and progress types - 943db1c (feat)
2. Task 2: Create scan queue coordinator and refactor Library for per-library scanning - 943db1c (feat)

Note: Tasks were merged into a single commit due to lint fix amend during pre-commit hook.

Files Created/Modified

• backend/library/scan_queue.go - Scan queue coordinator: ScanLibrary, ScanAllLibraries, CancelCurrentScan, CancelAllScans, drainQueue
• backend/library/library.go - Refactored Scan() → scanInternal() with library ID/name/path parameters, per-library DB queries
• backend/library/scan_control.go - Deprecated CancelScan() in favor of queue-aware methods
• backend/library/metrics.go - Added LibraryID, LibraryName to ScanMetrics; LibraryID, LibraryName, QueuedCount to ScanProgress
• backend/events/events.go - Added LibraryScanQueued and LibraryScanQueueDrained constants
• backend/database/sql/queries/audio_files.sql - Added library_id to CreateAudioFile INSERT
• backend/database/sql/sqlcgen/audio_files.sql.go - Regenerated with LibraryID in CreateAudioFileParams
• frontend/src/events.ts - Regenerated with scan queue events
• frontend/wailsjs/go/library/Library.d.ts - Auto-generated Wails bindings for new methods
• frontend/wailsjs/go/library/Library.js - Auto-generated Wails bindings for new methods
• frontend/wailsjs/go/models.ts - Auto-generated model updates

Decisions Made

• Library ID threading via importResult: Rather than adding a libraryID field to the Library struct, the ID is threaded through the scan pipeline via the importResult struct and set in the DB writer goroutine. This keeps the data flow explicit and avoids mutation of shared state.
• scanInternal returns only metrics: Changed signature from (*ScanMetrics, error) to *ScanMetrics since the scan queue coordinator calls it in a goroutine where error return is impractical. Errors are logged and accumulated in ScanMetrics.Warnings.
• Auto worker count per library: Each library path may reside on different storage (SSD vs HDD), so worker count uses ScanConcurrencyAuto with per-path detection rather than the global config value.
• Backward-compatible Scan(): Retained as deprecated wrapper that resolves the library from l.conf.DirectoryPath via GetLibraryByPath. This keeps handleConfigUpdate and FullRescan working without changes.

Deviations from Plan

None - plan executed exactly as written.

Issues Encountered

None

User Setup Required

None - no external service configuration required.

Next Phase Readiness

• Per-library scan pipeline complete, ready for Phase 11 Plan 02 (if exists) or Phase 12 (Library CRUD & Data Integrity)
• Frontend can now call ScanLibrary(id), ScanAllLibraries(), CancelCurrentScan(), CancelAllScans()
• Progress events include library identification for UI display
• Phase 12 can build library management UI on top of these Wails bindings

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Phase: 11-per-library-scan-pipeline Completed: 2026-03-09