app/cache.py

"""
Cache module for Auth microservice - Redis connection and caching utilities
"""
import redis
from typing import Optional, Any
import json
from app.core.config import settings
from app.core.logging import get_logger

logger = get_logger(__name__)


class CacheService:
    """Redis cache service for authentication system"""
    
    def __init__(self):
        self._redis_client: Optional[redis.Redis] = None
    
    def get_client(self) -> redis.Redis:
        """Get Redis client instance with connection pooling"""
        if self._redis_client is None:
            # Build connection pool parameters
            pool_params = {
                "host": settings.REDIS_HOST,
                "port": settings.REDIS_PORT,
                "db": settings.REDIS_DB,
                "decode_responses": True,
                "max_connections": 10,
                "socket_keepalive": True,
                "socket_connect_timeout": 5,
                "retry_on_timeout": True,
                "health_check_interval": 30
            }
            
            # Only add password if it's set
            if settings.REDIS_PASSWORD:
                pool_params["password"] = settings.REDIS_PASSWORD
            
            pool = redis.ConnectionPool(**pool_params)
            self._redis_client = redis.Redis(connection_pool=pool)
            logger.info(
                "Redis connected",
                extra={
                    "event": "redis_connected",
                    "redis_host": settings.REDIS_HOST,
                    "redis_port": settings.REDIS_PORT,
                    "redis_db": settings.REDIS_DB,
                },
            )
        return self._redis_client
    
    async def set(self, key: str, value: Any, ttl: int = 300) -> bool:
        """Set a value in cache with TTL"""
        try:
            client = self.get_client()
            serialized_value = json.dumps(value) if not isinstance(value, str) else value
            return client.setex(key, ttl, serialized_value)
        except Exception:
            logger.error("Cache set failed", exc_info=True, extra={"event": "cache_set_failure", "key": key})
            return False
    
    async def get(self, key: str) -> Optional[Any]:
        """Get a value from cache"""
        try:
            client = self.get_client()
            value = client.get(key)
            if value:
                try:
                    return json.loads(value)
                except json.JSONDecodeError:
                    return value
            return None
        except Exception:
            logger.error("Cache get failed", exc_info=True, extra={"event": "cache_get_failure", "key": key})
            return None
    
    async def delete(self, key: str) -> bool:
        """Delete a key from cache"""
        try:
            client = self.get_client()
            return client.delete(key) > 0
        except Exception:
            logger.error(
                "Cache delete failed",
                exc_info=True,
                extra={"event": "cache_delete_failure", "key": key},
            )
            return False


# Global cache instance
cache_service = CacheService()