feat: T03+T04 backend - FastAPI, DB models, Rentman integration, admin auth, APScheduler

backend/app/cache.py

@@ -0,0 +1,66 @@
+"""Redis cache client and helpers."""
+import json
+from typing import Any
+import redis.asyncio as redis
+from app.config import get_settings
+
+
+settings = get_settings()
+
+
+async def get_redis() -> redis.Redis:
+    """Return a Redis client instance."""
+    return redis.from_url(settings.redis_url, decode_responses=True)
+
+
+class CacheClient:
+    """Wrapper around Redis for equipment caching."""
+
+    def __init__(self) -> None:
+        self._redis: redis.Redis | None = None
+
+    async def connect(self) -> None:
+        self._redis = await get_redis()
+
+    async def disconnect(self) -> None:
+        if self._redis:
+            await self._redis.close()
+            self._redis = None
+
+    async def get(self, key: str) -> Any | None:
+        if not self._redis:
+            await self.connect()
+        assert self._redis is not None
+        data = await self._redis.get(key)
+        if data:
+            return json.loads(data)
+        return None
+
+    async def set(self, key: str, value: Any, ttl: int = 3600) -> None:
+        if not self._redis:
+            await self.connect()
+        assert self._redis is not None
+        await self._redis.setex(key, ttl, json.dumps(value, default=str))
+
+    async def delete_pattern(self, pattern: str) -> int:
+        if not self._redis:
+            await self.connect()
+        assert self._redis is not None
+        keys = []
+        async for key in self._redis.scan_iter(match=pattern):
+            keys.append(key)
+        if keys:
+            return await self._redis.delete(*keys)
+        return 0
+
+    async def incr_rate(self, key: str, window: int = 60) -> int:
+        if not self._redis:
+            await self.connect()
+        assert self._redis is not None
+        count = await self._redis.incr(key)
+        if count == 1:
+            await self._redis.expire(key, window)
+        return count
+
+
+cache = CacheClient()