Files
bambuddy/backend/app/services/obico_detection.py
T
maziggy eec7793955 feat(obico): AI print-failure detection via self-hosted Obico ML API (#172)
Adds a Failure Detection tab under Settings that wires Bambuddy to a
  self-hosted Obico ml_api container — no cloud, no account, no WebSocket.
  While a print is running, the detection service periodically hands the
  printer's camera snapshot URL to the ML API and smooths scores over
  time (30-frame warmup + EWM, alpha=2/13, short/long rolling means) so
  one noisy frame can't trigger an action. When the smoothed score
  crosses HIGH, the configured action fires exactly once per print:
  notify, pause, or pause-and-cut-power (via linked smart plugs).

  - Backend: new obico_detection + obico_smoothing + obico_actions
    services, /obico/status and /obico/test-connection routes
    (SETTINGS_READ / SETTINGS_UPDATE), six obico_* AppSettings fields
    with validators for sensitivity/action/enabled_printers.
  - Frontend: FailureDetectionSettings component (enable, ML URL + test,
    sensitivity, action, poll interval, per-printer monitor list, live
    status + detection history), new sidebar tab with service-active
    bullet, toast on save.
  - Tests: 17 detection unit tests + 15 smoothing unit tests + 4
    frontend component tests.
  - Docs: README bullet, CHANGELOG entry, wiki page under Analytics,
    website features.html entry.
2026-04-13 09:54:26 +02:00

245 lines
9.3 KiB
Python

"""Obico AI print-failure detection service.
Polls a self-hosted Obico ML API with snapshots from each monitored printer
while a print is running, smooths scores over time, and dispatches a configured
action (notify / pause / pause_and_off) when a sustained failure is detected.
See `obico_smoothing.py` for the per-print EWM + rolling-mean math.
"""
import asyncio
import json
import logging
from collections import deque
from datetime import datetime, timezone
import httpx
from sqlalchemy import select
from backend.app.core.database import async_session
from backend.app.models.settings import Settings
from backend.app.services.obico_smoothing import (
PrintState,
classify,
score_from_detections,
thresholds,
)
logger = logging.getLogger(__name__)
HISTORY_MAX = 50
HEALTH_TIMEOUT = 5.0
DETECTION_TIMEOUT = 30.0
class ObicoDetectionService:
"""Singleton service that polls the ML API and acts on sustained failures."""
def __init__(self):
self._task: asyncio.Task | None = None
# printer_id -> PrintState (reset when a new print starts)
self._states: dict[int, PrintState] = {}
# printer_id -> task_name active when state was created (used to detect new prints)
self._state_keys: dict[int, str] = {}
# printer_id -> last classification ("safe"/"warning"/"failure")
self._last_class: dict[int, str] = {}
# printer_id -> whether an action has already been fired for the current print
self._action_fired: dict[int, bool] = {}
# Global detection event log (most-recent-first)
self._history: deque = deque(maxlen=HISTORY_MAX)
self._last_error: str | None = None
# ---- lifecycle ----
async def start(self):
if self._task is not None:
return
logger.info("Starting Obico detection service")
self._task = asyncio.create_task(self._loop())
def stop(self):
if self._task:
self._task.cancel()
self._task = None
logger.info("Stopped Obico detection service")
# ---- settings ----
async def _load_settings(self) -> dict:
keys = [
"obico_enabled",
"obico_ml_url",
"obico_sensitivity",
"obico_action",
"obico_poll_interval",
"obico_enabled_printers",
"external_url",
]
async with async_session() as db:
result = await db.execute(select(Settings).where(Settings.key.in_(keys)))
rows = {r.key: r.value for r in result.scalars().all()}
enabled_printers_raw = rows.get("obico_enabled_printers", "")
if enabled_printers_raw:
try:
enabled_printers = set(json.loads(enabled_printers_raw))
except json.JSONDecodeError:
enabled_printers = set()
else:
enabled_printers = None # None = all printers
return {
"enabled": rows.get("obico_enabled", "false").lower() == "true",
"ml_url": (rows.get("obico_ml_url") or "").rstrip("/"),
"sensitivity": rows.get("obico_sensitivity", "medium"),
"action": rows.get("obico_action", "notify"),
"poll_interval": int(rows.get("obico_poll_interval", "10")),
"enabled_printers": enabled_printers,
"external_url": (rows.get("external_url") or "").rstrip("/"),
}
# ---- main loop ----
async def _loop(self):
"""Poll active printers while enabled. Adjusts interval from settings each cycle."""
while True:
try:
settings = await self._load_settings()
interval = max(5, settings.get("poll_interval", 10))
if not settings["enabled"] or not settings["ml_url"]:
await asyncio.sleep(interval)
continue
if not settings["external_url"]:
# Without a reachable base URL, the ML API can't fetch snapshots.
self._last_error = "external_url not set — ML API cannot reach snapshot endpoint"
await asyncio.sleep(interval)
continue
await self._poll_once(settings)
await asyncio.sleep(interval)
except asyncio.CancelledError:
break
except Exception as e:
logger.error("Obico detection loop error: %s", e)
self._last_error = str(e)
await asyncio.sleep(30)
async def _poll_once(self, settings: dict):
# Late import to avoid cycles at module load time
from backend.app.services.printer_manager import printer_manager
statuses = printer_manager.get_all_statuses()
for printer_id, status in list(statuses.items()):
if settings["enabled_printers"] is not None and printer_id not in settings["enabled_printers"]:
continue
if not printer_manager.is_connected(printer_id):
continue
if not status or getattr(status, "state", None) != "RUNNING":
# Reset state when not printing so the next print starts fresh
self._states.pop(printer_id, None)
self._state_keys.pop(printer_id, None)
self._action_fired.pop(printer_id, None)
continue
await self._check_printer(printer_id, status, settings)
async def _check_printer(self, printer_id: int, status, settings: dict):
task_name = getattr(status, "task_name", None) or getattr(status, "subtask_name", "") or ""
key = f"{task_name}"
if self._state_keys.get(printer_id) != key:
self._states[printer_id] = PrintState()
self._state_keys[printer_id] = key
self._action_fired[printer_id] = False
snapshot_url = f"{settings['external_url']}/api/v1/printers/{printer_id}/camera/snapshot"
ml_url = f"{settings['ml_url']}/p/"
try:
async with httpx.AsyncClient(timeout=DETECTION_TIMEOUT) as client:
resp = await client.get(ml_url, params={"img": snapshot_url})
resp.raise_for_status()
payload = resp.json()
except Exception as e:
self._last_error = f"ML API call failed for printer {printer_id}: {e}"
logger.warning(self._last_error)
return
detections = payload.get("detections", []) if isinstance(payload, dict) else []
current_p = score_from_detections(detections)
state = self._states[printer_id]
score = state.update(current_p)
verdict = classify(score, settings["sensitivity"])
self._last_class[printer_id] = verdict
# Log every non-safe sample — safe samples would flood history
if verdict != "safe" or detections:
self._history.appendleft(
{
"printer_id": printer_id,
"task_name": task_name,
"timestamp": datetime.now(timezone.utc).isoformat(),
"current_p": round(current_p, 4),
"score": round(score, 4),
"class": verdict,
"detections": len(detections),
}
)
if verdict == "failure" and not self._action_fired.get(printer_id):
self._action_fired[printer_id] = True
await self._dispatch_action(printer_id, settings["action"], task_name, score)
async def _dispatch_action(self, printer_id: int, action: str, task_name: str, score: float):
from backend.app.services.obico_actions import execute_action
logger.warning(
"Obico: failure detected on printer %s (task=%r score=%.3f) — action=%s",
printer_id,
task_name,
score,
action,
)
try:
await execute_action(printer_id, action, task_name, score)
except Exception as e:
self._last_error = f"Action dispatch failed: {e}"
logger.error(self._last_error)
# ---- queries ----
def get_status(self) -> dict:
low, high = thresholds("medium")
return {
"is_running": self._task is not None and not self._task.done(),
"last_error": self._last_error,
"per_printer": {
pid: {
"class": self._last_class.get(pid, "safe"),
"frame_count": state.frame_count,
"score": round(state.ewm_mean, 4),
}
for pid, state in self._states.items()
},
"thresholds": {"low": low, "high": high},
"history": list(self._history),
}
async def test_connection(self, url: str) -> dict:
"""Ping the ML API health endpoint. Returns {ok, status_code, body, error}."""
target = f"{url.rstrip('/')}/hc/"
try:
async with httpx.AsyncClient(timeout=HEALTH_TIMEOUT) as client:
resp = await client.get(target)
body = resp.text.strip()
return {
"ok": resp.status_code == 200 and body.lower() == "ok",
"status_code": resp.status_code,
"body": body,
"error": None,
}
except Exception as e:
return {"ok": False, "status_code": None, "body": None, "error": str(e)}
obico_detection_service = ObicoDetectionService()