Files
SmartThings-Local/samsung_appliance/state_cache.py
T
Jack Nagy 709fdf444d Refactor to polling-first architecture with OBSERVE as accelerator
State freshness now comes from a tiered PollScheduler over the persistent
DTLS session; OBSERVE registrations are kept as an opportunistic
acceleration layer. Behaviour is identical online vs air-gapped except
for worst-case freshness latency.

Adds three modules:
- StateCache: single source of truth, source-tagged change events
- PollScheduler: hot/warm/cold + sweep tiers, write-defer past the
  fetchback-revert window, per-window RTT/slow-poll tracking
- KeepaliveTask: CoAP empty-CON ping with consecutive-fail detection
  driving MQTT availability

Bridge publishes per-appliance diagnostic entities (Push Active, Last
Update Source, Poll Max RTT, Slow Polls, Poll Errors, Stalest Resource
Age, Last OBSERVE Age) under HA's Diagnostic section. Tier cadences
are descriptor-declared, calibrated against measured per-firmware
ceilings (dryer ~14 req/s, oven ~8 req/s via probe_poll_rate_combined.py).

Drops HEARTBEAT_INTERVAL_S in favour of the descriptor-declared sweep
tier; PING_INTERVAL_S now consumed by KeepaliveTask inside the bridge
rather than driven from main.py.

README explains the push/poll split and what happens when the appliance
is blocked from internet.
2026-06-03 18:38:04 +01:00

79 lines
2.6 KiB
Python

"""Single source of truth for one appliance's state.
All writers (OBSERVE notify, poll, seed, optimistic) call apply_rep().
A registered on_change callback fires after any apply that mutated the
cache, which the bridge wires to its MQTT publish gate.
"""
from __future__ import annotations
import threading
import time
from typing import Callable, Optional, TYPE_CHECKING
if TYPE_CHECKING:
from .appliances.base import ApplianceDescriptor
class StateCache:
def __init__(self, descriptor: 'ApplianceDescriptor'):
self.descriptor = descriptor
self.links: dict[str, dict] = {}
self.last_updated: dict[str, float] = {}
self.source: dict[str, str] = {}
self.descriptor_state: dict = {}
self._on_change: Optional[Callable[[bool, str], None]] = None
self._lock = threading.RLock()
def set_on_change(self, cb: Callable[[bool, str], None]) -> None:
self._on_change = cb
def apply_rep(self, href: str, rep: dict, source: str) -> bool:
if not isinstance(rep, dict):
return False
with self._lock:
prior = self.links.get(href)
changed = prior != rep
self.links[href] = rep
self.last_updated[href] = time.time()
self.source[href] = source
hook = self.descriptor.on_observation
if hook is not None:
try:
hook(self.descriptor_state, href, rep)
except Exception:
pass
if self._on_change is not None:
try:
self._on_change(changed, source)
except Exception:
pass
return changed
def apply_optimistic(self, href: str, body: dict) -> bool:
if not isinstance(body, dict):
return False
with self._lock:
merged = dict(self.links.get(href) or {})
merged.update(body)
return self.apply_rep(href, merged, source='optimistic')
def get(self, href: str) -> Optional[dict]:
with self._lock:
return self.links.get(href)
def snapshot(self) -> dict[str, dict]:
with self._lock:
return dict(self.links)
def freshness_s(self, href: str) -> Optional[float]:
ts = self.last_updated.get(href)
return None if ts is None else (time.time() - ts)
def stalest(self) -> Optional[tuple[str, float]]:
with self._lock:
if not self.last_updated:
return None
href = min(self.last_updated, key=self.last_updated.get)
return href, time.time() - self.last_updated[href]