iptvnator-sqlite-db-worker

# IPTVnator SQLite DB Worker ## Ownership and Flow - Renderer service: `libs/services/src/lib/database-electron.service.ts` - Preload API: `apps/electron-backend/src/app/api/main.preload.ts` - IPC handlers: `apps/electron-backend/src/app/events/database/` - Client: `apps/electron-backend/src/app/services/database-worker-client.ts` - Protocol: `apps/electron-backend/src/app/workers/database-worker.types.ts` - Thin dispatcher: `apps/electron-backend/src/app/workers/database.worker.ts` - Connection: `apps/electron-backend/src/app/workers/database.worker-connection.ts` - Runtime paths: `apps/electron-backend/src/app/workers/worker-runtime-paths.ts` - SQL operations: `apps/electron-backend/src/app/database/operations/` - Shared schema: `libs/shared/database/src/lib/schema.ts` - Bundler: `apps/electron-backend/build-worker.js` - Canonical guide: `docs/architecture/sqlite-db-worker.md` The chain is renderer `DatabaseService` → preload IPC → main event handler → `DatabaseWorkerClient` and its request protocol → worker dispatcher → worker connection → operation module → shared `@iptvnator/shared/database/schema`, then response or request-scoped event back to the originating renderer. Keep SQL-heavy logic in operation modules and the worker entrypoint focused on dispatch/orchestration. The build script produces three bundles: EPG parser, database, and playlist refresh. EPG parsing stays in its dedicated worker. Do not silently migrate lightweight download handlers or EPG-specific main-process query/mapping/fetch handlers as part of unrelated database work. ## Identity, Progress, and Cancellation `requestId` is generated for every client request and correlates worker event/response transport. `operationId` is the renderer-visible identity for long-operation progress and cooperative cancellation. Tracked operations are save content, delete Xtream content, restore Xtream user data, delete playlist, and delete all playlists. The first four are cancellable. Delete-all is deliberately tracked with `cancellable: false`. Cancellation is cooperative at chunk checkpoints. Committed chunks remain committed and the request finally rejects with `AbortError`. For the operation/busy lifecycle, only a terminal completed/error/cancelled event settles UI state; a cancel-requested flag may update immediately. Inside synchronous `better-sqlite3` transactions, prepared writes must use `.run()`. `.execute()` defers work and can commit a silent no-op. ## Rebuild and Verify After worker source changes: ```bash pnpm nx test electron-backend pnpm nx run electron-backend:build-worker stat dist/apps/electron-backend/workers/database.worker.js ``` Confirm the artifact timestamp, restart Electron, then run the closest Electron E2E or CDP workflow. For SQL output, `IPTVNATOR_TRACE_DB=1` and `IPTVNATOR_TRACE_SQL=1` emit only fixed, allowlisted statement types through the shared redacting summary in `libs/shared/logging/src/lib/sql-trace-summary.ts`; never log expanded SQL or bound values. DB transport traces remain separately redacted.