feat: moonraker websocket status worker

[peterus]

Summary

Adds a long-running asyncio worker that holds a persistent WebSocket connection to each configured Moonraker printer, consumes status notifications, and updates PrintQueue entries in the database. This finally fixes the original problem: server-side print-end detection now works without relying on an open browser tab.

Builds on the `PrinterBackend` abstraction from #24.

Architecture

• `core/services/moonraker_ws.py` — one websocket per printer with exponential reconnect backoff. Subscribes to `print_stats`, `virtual_sdcard`, `display_status`, `heater_bed`, `extruder`. Supports Moonraker oneshot-token auth via `/access/oneshot_token` when an API key is configured; unauthenticated otherwise.
• `core/services/printer_status_sync.py` — pure sync event → DB logic. Handles `notify_history_changed` (primary job-end trigger) and `notify_status_update` (progress + fallback terminal detection). Progress writes throttled to 5 s per entry.
• `core/management/commands/moonraker_worker.py` — process entry point. Enables SQLite WAL + `busy_timeout=5000`, runs an `asyncio.TaskGroup` with a reconciler task that polls `PrinterProfile` every `WORKER_RELOAD_INTERVAL` seconds (default 10 s) and spawns/cancels/restarts per-printer tasks on add/remove/change — live reload, no container restart needed on printer config changes.

Model & View Changes

• `PrintQueue` gains `progress`, `status_updated_at`, `last_error` fields (migration `0016`).
• `QueueCheckPrinterStatusView` no longer talks to Moonraker directly — it reads the worker-populated DB fields and exposes a `worker_stale` flag when `status_updated_at` is older than 60 s (or absent). Response shape stays backwards compatible for the existing `polling.js`.
• `moonraker.get_job_status()` reuses a shared `map_klipper_state()` helper so the WS worker and REST client stay in sync.

Deployment

• New docker-compose service `worker` using the same `release` image, entrypoint overridden to skip `migrate`/`collectstatic` (handled by `web`).
• `requirements.txt`: `websockets>=14,<16`.

Test Plan

• 65 unit tests across all affected modules pass locally (`test_services_printer_status_sync`, `test_services_moonraker_ws`, `test_services_moonraker`, `test_services_printer_backend`, `test_services_queue`, `test_management_moonraker_worker`).
• `ruff format --check .` + `ruff check .` clean.
• `makemigrations --check --dry-run` → no changes detected.
• Manual e2e against real Klipper printer: start a short job, close the browser, verify the queue entry flips to `awaiting_review` and `completed_at` is populated without any tab being open.
• Live reload test: start worker, add/edit/remove a printer in admin, verify logs show the corresponding spawn/cancel within ~10 s.
• Reconnect test: kill Moonraker mid-print, verify backoff log and clean resume.
• SQLite lock check: drive Gunicorn with curl while worker writes progress, verify no "database is locked" errors.

Out of Scope

• Prometheus metrics / worker healthchecks
• Admin UI for worker status
• Django Channels push to browser (frontend keeps polling, just cheaper now)
• Bambu / MQTT backends (separate PR when hardware is available)

🤖 Generated with Claude Code

[Copilot]

Pull request overview

Adds a server-side Moonraker WebSocket worker that keeps printer status/progress up to date in the DB, enabling reliable print-end detection without relying on browser polling.

Changes:

• Introduces a long-running moonraker_worker management command that maintains per-printer WebSocket connections and live-reloads printer config changes.
• Adds PrintQueue.progress, PrintQueue.status_updated_at, and PrintQueue.last_error fields plus sync event→DB logic (printer_status_sync).
• Updates the queue status polling endpoint to read from DB fields and emit a worker_stale hint instead of calling Moonraker directly.

Reviewed changes

Copilot reviewed 11 out of 14 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
requirements.txt	Adds websockets dependency needed for the Moonraker WS client.
docker-compose.yml	Adds a dedicated worker service to run the management command.
core/views/queue.py	Changes /api/queue/<pk>/check-status/ to serve worker-populated DB status/progress (+ staleness).
core/models/queue.py	Adds progress, status_updated_at, last_error fields to PrintQueue.
core/migrations/0016_printqueue_progress_fields.py	Migration adding the new PrintQueue fields.
core/services/moonraker.py	Adds shared map_klipper_state() helper for consistent state normalization.
core/services/moonraker_ws.py	Implements the Moonraker JSON-RPC WebSocket client + oneshot token helper.
core/services/printer_status_sync.py	Adds sync notification handling + throttled progress writes + terminal transitions.
core/management/commands/moonraker_worker.py	Adds the asyncio TaskGroup worker/reconciler process entry point and SQLite WAL tuning.
core/tests/test_services_printer_status_sync.py	Unit tests for event→DB transition logic and progress throttling.
core/tests/test_services_moonraker_ws.py	Unit tests for WS URL building and oneshot-token fetching behavior.
core/tests/test_management_moonraker_worker.py	Tests for reconciler behavior (spawn/cancel/restart).

[github-actions]

Preview image ready

By tag:

docker pull ghcr.io/peterus/layernexus:pr-25

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docker pull ghcr.io/peterus/layernexus@sha256:b57a343e90c4091aeed6570e3c6f928a51620966053a6d1d357fee0cc476843c

_{Commit: 650d80c8274fee6dcf449dbacd651fb20685755c}