refactor(rain): enhance fetch_precip_series_nws with caching support

- Added cache_ttl parameter to fetch_precip_series_nws to enable caching of results for improved performance.
- Implemented logic to reuse cached results based on location and cache expiration.
- Updated tests to ensure proper handling of cache_ttl without causing errors.
- Refactored WorldCupFastcastClient to streamline connection handling and improve readability.

modules/clients/worldcup_fastcast.py

@@ -105,9 +105,9 @@ class WorldCupFastcastClient:
 
     async def _connect_once(self) -> None:
         headers = {"Origin": ORIGIN, "User-Agent": USER_AGENT}
-        async with aiohttp.ClientSession(headers=headers) as session:
-            timeout = aiohttp.ClientTimeout(total=self.connect_timeout)
-            async with session.get(WEBSOCKET_HOST_URL, timeout=timeout) as resp:
+        timeout = aiohttp.ClientTimeout(total=self.connect_timeout)
+        async with aiohttp.ClientSession(headers=headers, timeout=timeout) as session:
+            async with session.get(WEBSOCKET_HOST_URL) as resp:
                 resp.raise_for_status()
                 host = await resp.json()
 
@@ -117,7 +117,7 @@ class WorldCupFastcastClient:
                 raise ValueError("fastcast websockethost returned no ip")
 
             url = f"wss://{ip}:{port}/FastcastService/pubsub/profiles/{self.profile}?TrafficId={uuid.uuid4()}"
-            async with session.ws_connect(url, timeout=self.connect_timeout, heartbeat=25, origin=ORIGIN) as ws:
+            async with session.ws_connect(url, heartbeat=25, origin=ORIGIN) as ws:
                 self.logger.info("Fastcast connected (topic=%s)", self.topic)
                 async for msg in ws:
                     if msg.type == aiohttp.WSMsgType.TEXT:

modules/commands/rain_command.py

@@ -486,6 +486,7 @@ def fetch_precip_series_nws(
     timeout: int = 10,
     logger: Any = None,
     pop_floor: int = 50,
+    cache_ttl: float = 0.0,
 ) -> Optional[dict]:
     """Build a precip nowcast series from the NWS gridpoint forecast (US only).
 
@@ -499,7 +500,16 @@ def fetch_precip_series_nws(
     probability rather than snapping to coarse 6-hour QPF boundaries, and a trace
     of QPF at a low chance is not reported as rain. Times are naive UTC ISO strings
     (they only need to be self-consistent: the nowcast works on relative minutes).
+
+    When cache_ttl > 0, a fresh prior result for the same rounded location is reused
+    (shared bounded cache with fetch_precip_series).
     """
+    cache_key = (round(lat, 2), round(lon, 2), "nws")
+    if cache_ttl > 0:
+        hit = _SERIES_CACHE.get(cache_key)
+        if hit is not None and (time.time() - hit[0]) < cache_ttl:
+            return hit[1]
+
     headers = {"User-Agent": "(meshcore-bot, weather-nowcast)", "Accept": "application/geo+json"}
     try:
         pts = session.get(
@@ -547,7 +557,7 @@ def fetch_precip_series_nws(
         precip.append(amt)
         codes.append(_nws_weather_code(wx.get(h)) if amt else None)
 
-    return {
+    result = {
         "times": times,
         "precip": precip,
         "codes": codes,
@@ -556,6 +566,11 @@ def fetch_precip_series_nws(
         "current_code": codes[0] if codes else None,
         "step": 60,
     }
+    if cache_ttl > 0:
+        if len(_SERIES_CACHE) >= _SERIES_CACHE_CAP:
+            _SERIES_CACHE.pop(next(iter(_SERIES_CACHE)))
+        _SERIES_CACHE[cache_key] = (time.time(), result)
+    return result
 
 
 @dataclass

modules/commands/worldcup_command.py

@@ -15,7 +15,7 @@ World Cup data is also reachable year-round through the `sports` command
 front end with live scores, standings, and nation lookups.
 """
 
-from typing import TYPE_CHECKING, Optional
+from typing import TYPE_CHECKING
 
 from ..clients.espn_client import ESPNClient
 from ..clients.sports_mappings import SPORT_EMOJIS
@@ -50,8 +50,6 @@ class WorldCupCommand(BaseCommand):
         {"name": "nation", "description": "A nation's matches (e.g. brazil, usa)"},
     ]
 
-    espn_client: Optional[ESPNClient] = None
-
     def __init__(self, bot: "MeshCoreBot"):
         """Initialize the World Cup command with an ESPN client and data helper."""
         super().__init__(bot)
@@ -62,7 +60,7 @@ class WorldCupCommand(BaseCommand):
 
         cache_ttl_minutes = self.get_config_value("Worldcup_Command", "cache_ttl_minutes", fallback=360, value_type="int")
 
-        self.espn_client = ESPNClient(logger=self.logger, timeout=self.url_timeout)
+        self.espn_client: ESPNClient = ESPNClient(logger=self.logger, timeout=self.url_timeout)
         self.wc_data = WorldCupData(self.espn_client, logger=self.logger, cache_ttl=cache_ttl_minutes * 60)
 
     def matches_keyword(self, message: MeshMessage) -> bool: