M8-R06: refresh Tibber prices after startup and configuration

app/services/tibber_prices.py

@@ -30,6 +30,7 @@ Design decisions
 from __future__ import annotations
 
 import logging
+from threading import Lock, Thread
 from datetime import UTC, datetime
 
 from sqlalchemy import select
@@ -41,7 +42,10 @@ from app.models.energy import EnergyContract, TibberPrice
 logger = logging.getLogger(__name__)
 
 
-def _active_tibber_contract_exists(session: Session) -> bool:
+_background_refresh_lock = Lock()
+
+
+def active_tibber_contract_exists(session: Session) -> bool:
     """Return True if there is an active contract with kind='tibber'."""
     row = session.execute(
         select(EnergyContract).where(
@@ -84,14 +88,17 @@ def refresh_prices(session: Session, settings: object) -> int:
         logger.debug("refresh_prices: tibber_api_token is empty — no-op")
         return 0
 
-    if not _active_tibber_contract_exists(session):
+    if not active_tibber_contract_exists(session):
         logger.debug("refresh_prices: no active tibber contract — no-op")
         return 0
 
     home_id: str = getattr(settings, "tibber_home_id", "") or ""
     home_id_or_none: str | None = home_id.strip() or None
 
-    logger.info("refresh_prices: fetching Tibber price range (home_id=%r)", home_id_or_none)
+    # Neither the API token nor the selected home identifier is safe to emit in
+    # diagnostics.  The fetch client receives them, but logs only describe the
+    # operation itself.
+    logger.info("refresh_prices: fetching Tibber price range")
 
     # May raise TibberError or TibberAuthError — let them propagate.
     price_points = fetch_price_range(token, home_id_or_none)
@@ -137,3 +144,59 @@ def refresh_prices(session: Session, settings: object) -> int:
 
     logger.info("refresh_prices: upserted %d price points", upserted)
     return upserted
+
+
+def run_tibber_refresh_best_effort() -> bool:
+    """Run one refresh with an isolated session, skipping concurrent requests.
+
+    This is shared by the hourly scheduler and immediate post-commit triggers.
+    It intentionally catches all failures: refresh is advisory and must never
+    make app startup or a successfully committed configuration/contract update
+    appear to have failed.  The boolean reports whether this invocation owned
+    the work; it is primarily useful for tests and diagnostics.
+    """
+    if not _background_refresh_lock.acquire(blocking=False):
+        logger.debug("Tibber refresh already running; skipping duplicate request")
+        return False
+
+    session: Session | None = None
+    try:
+        # Local imports keep the pure refresh service free of app startup import
+        # cycles, while every background invocation gets a fresh DB session.
+        from app.config import get_settings
+        from app.db import get_session_local
+        from app.services.config_page import build_runtime_settings
+
+        session = get_session_local()()
+        refresh_prices(session, build_runtime_settings(session, get_settings()))
+    except Exception as exc:
+        # Exception text can contain remote request details.  Keep diagnostics
+        # useful without allowing a token or home id to escape through logging.
+        logger.warning("Tibber price refresh failed (%s)", type(exc).__name__)
+        if session is not None:
+            try:
+                session.rollback()
+            except Exception:
+                logger.warning("Tibber price refresh rollback failed")
+    finally:
+        if session is not None:
+            try:
+                session.close()
+            except Exception:
+                logger.warning("Tibber price refresh session close failed")
+        _background_refresh_lock.release()
+    return True
+
+
+def trigger_tibber_refresh() -> None:
+    """Request a non-blocking, best-effort Tibber refresh after a DB commit."""
+    try:
+        Thread(
+            target=run_tibber_refresh_best_effort,
+            name="tibber-price-refresh",
+            daemon=True,
+        ).start()
+    except Exception as exc:
+        # Starting the optional worker must not turn an already committed API
+        # operation into a failure; avoid logging exception text for secrecy.
+        logger.warning("Unable to start Tibber price refresh (%s)", type(exc).__name__)