initial commit

api/app/services/dashboard.py

@@ -0,0 +1,67 @@
+from __future__ import annotations
+
+import asyncio
+import logging
+from typing import Any
+
+from app.cache import cache_get, cache_set
+from app.config import CACHE_TTL_DASHBOARD, CACHE_TTL_OBSERVATIONS, CACHE_TTL_WARNINGS
+from app.services.dwd_radar import fetch_radar_index
+from app.services.warnings import fetch_warnings_for_location
+from app.services.weather import get_forecast, get_observations
+
+logger = logging.getLogger(__name__)
+
+
+async def get_radar_summary() -> dict[str, Any]:
+    redis_key = "radar:summary"
+    cached = await cache_get(redis_key)
+    if cached:
+        return {**cached, "cached": True}
+
+    index = await fetch_radar_index(limit=12)
+    payload = {
+        "source": index["source"],
+        "product": index["product"],
+        "count": index["count"],
+        "cached": False,
+    }
+    await cache_set(redis_key, payload, 120)
+    return payload
+
+
+async def build_dashboard(lat: float, lon: float, local_only: bool = True) -> dict[str, Any]:
+    redis_key = f"dashboard:{round(lat, 4)}:{round(lon, 4)}:{int(local_only)}"
+    cached = await cache_get(redis_key)
+    if cached:
+        return {**cached, "bundle_cached": True}
+
+    results = await asyncio.gather(
+        get_forecast(lat, lon),
+        get_observations(lat, lon),
+        fetch_warnings_for_location(lat, lon, local_only=local_only),
+        get_radar_summary(),
+        return_exceptions=True,
+    )
+
+    payload: dict[str, Any] = {
+        "lat": lat,
+        "lon": lon,
+        "bundle_cached": False,
+        "errors": {},
+    }
+
+    names = ("forecast", "observations", "warnings", "radar")
+    for name, result in zip(names, results):
+        if isinstance(result, Exception):
+            logger.warning("dashboard %s failed: %s", name, result)
+            payload["errors"][name] = str(result)
+            payload[name] = None
+        else:
+            payload[name] = result
+
+    ttl = min(CACHE_TTL_DASHBOARD, CACHE_TTL_OBSERVATIONS, CACHE_TTL_WARNINGS)
+    if not payload["errors"]:
+        await cache_set(redis_key, payload, ttl)
+
+    return payload