refactor(cache): improve redis client initialization with better error handling

Add connection timeout settings and fallback mechanism for authentication failures
Move client creation to separate function for lazy initialization

app/core/cache_client.py

@@ -1,6 +1,6 @@
 import logging
 from redis.asyncio import Redis
-from redis.exceptions import RedisError
+from redis.exceptions import RedisError, ConnectionError, AuthenticationError
 from app.core.config import settings
 
 logger = logging.getLogger(__name__)
@@ -9,31 +9,71 @@ logger = logging.getLogger(__name__)
 CACHE_HOST, CACHE_PORT = settings.CACHE_URI.split(":")
 CACHE_PORT = int(CACHE_PORT)
 
-try:
-    # Configure Redis client based on whether password is provided and not empty
-    if settings.CACHE_K and settings.CACHE_K.strip():
-        redis_client = Redis(
-            host=CACHE_HOST,
-            port=CACHE_PORT,
-            username="default",
-            password=settings.CACHE_K,
-            decode_responses=True
-        )
-        logger.info(f"Connected to Redis at {CACHE_HOST}:{CACHE_PORT} with authentication")
-    else:
-        # Local Redis without authentication
-        redis_client = Redis(
-            host=CACHE_HOST,
-            port=CACHE_PORT,
-            decode_responses=True
-        )
-        logger.info(f"Connected to Redis at {CACHE_HOST}:{CACHE_PORT} without authentication")
-except RedisError as e:
-    logger.error(f"Failed to connect to Redis: {e}")
-    raise
-except Exception as e:
-    logger.error(f"Unexpected error connecting to Redis: {e}")
-    raise
+async def create_redis_client():
+    """Create Redis client with proper error handling and fallback"""
+    try:
+        # First try with authentication if password is provided
+        if settings.CACHE_K and settings.CACHE_K.strip():
+            redis_client = Redis(
+                host=CACHE_HOST,
+                port=CACHE_PORT,
+                username="default",
+                password=settings.CACHE_K,
+                decode_responses=True,
+                socket_connect_timeout=5,
+                socket_timeout=5,
+                retry_on_timeout=True
+            )
+            # Test the connection
+            await redis_client.ping()
+            logger.info(f"Connected to Redis at {CACHE_HOST}:{CACHE_PORT} with authentication")
+            return redis_client
+        else:
+            # Try without authentication for local Redis
+            redis_client = Redis(
+                host=CACHE_HOST,
+                port=CACHE_PORT,
+                decode_responses=True,
+                socket_connect_timeout=5,
+                socket_timeout=5,
+                retry_on_timeout=True
+            )
+            # Test the connection
+            await redis_client.ping()
+            logger.info(f"Connected to Redis at {CACHE_HOST}:{CACHE_PORT} without authentication")
+            return redis_client
+            
+    except AuthenticationError as e:
+        logger.warning(f"Authentication failed for Redis: {e}")
+        # Try without authentication as fallback
+        try:
+            redis_client = Redis(
+                host=CACHE_HOST,
+                port=CACHE_PORT,
+                decode_responses=True,
+                socket_connect_timeout=5,
+                socket_timeout=5,
+                retry_on_timeout=True
+            )
+            await redis_client.ping()
+            logger.info(f"Connected to Redis at {CACHE_HOST}:{CACHE_PORT} without authentication (fallback)")
+            return redis_client
+        except Exception as fallback_error:
+            logger.error(f"Redis fallback connection also failed: {fallback_error}")
+            raise
+            
+    except ConnectionError as e:
+        logger.error(f"Failed to connect to Redis at {CACHE_HOST}:{CACHE_PORT}: {e}")
+        raise
+    except Exception as e:
+        logger.error(f"Unexpected error connecting to Redis: {e}")
+        raise
+
+# Initialize Redis client
+redis_client = None
 
 async def get_redis() -> Redis:
+    global redis_client
+    if redis_client is None:
+        redis_client = await create_redis_client()
     return redis_client