production-evyos-systems-an.../ServicesRunner/Depends/redis_handlers.py

161 lines
6.0 KiB
Python

import logging
from contextlib import contextmanager
from time import sleep
from redis import Redis, RedisError, ConnectionError as RedisConnectionError
from Depends.config import ConfigServices, RedisConfig
# Configure logging
logger = logging.getLogger('Redis_Handler')
@contextmanager
def safe_redis_operation(redis_client: Redis, operation_name: str = "Redis operation"):
"""
Context manager for safely executing Redis operations with error handling
"""
try:
yield redis_client
except RedisConnectionError as e:
logger.error(f"{operation_name} failed due to Redis connection error: {str(e)}")
raise
except RedisError as e:
logger.error(f"{operation_name} failed due to Redis error: {str(e)}")
raise
except Exception as e:
logger.error(f"{operation_name} failed with unexpected error: {str(e)}")
raise
class RedisHandler:
"""Singleton Redis handler class for centralized Redis operations"""
# Singleton instance
_instance = None
# Redis exceptions constant for unified error handling
REDIS_EXCEPTIONS = (RedisConnectionError, RedisError)
def __new__(cls):
if cls._instance is None:
cls._instance = super(RedisHandler, cls).__new__(cls)
cls._instance._initialized = False
return cls._instance
def __init__(self):
# Initialize only once
if self._initialized:
return
# Initialize Redis client with retry logic
self.redis_client = self._create_redis_client()
self.redis_connected = self._check_redis_connection()
self._initialized = True
def _create_redis_client(self):
"""Create a Redis client with connection retry"""
max_retries = 5
retry_delay = 5
for attempt in range(max_retries):
try:
client = Redis(**RedisConfig.as_dict())
client.ping() # Test the connection
logger.info("Redis connection established successfully")
return client
except (RedisConnectionError, RedisError) as e:
if attempt < max_retries - 1:
logger.warning(f"Redis connection attempt {attempt + 1} failed: {str(e)}. Retrying in {retry_delay} seconds...")
sleep(retry_delay)
retry_delay *= 2 # Exponential backoff
else:
logger.error(f"Failed to connect to Redis after {max_retries} attempts: {str(e)}")
# Continue with a new Redis client instance even if ping fails
# This allows the service to start and retry connections later
return Redis(**RedisConfig.as_dict())
def _check_redis_connection(self) -> bool:
"""Check if Redis connection is alive"""
try:
self.ping()
return True
except Exception as e:
return False
def ping(self):
"""Ping Redis server to check connection"""
return self.redis_client.ping()
def sadd(self, key: str, value):
"""Add a value to a Redis set"""
return self.redis_client.sadd(key, value)
def get(self, key: str):
"""Get a value from Redis by key"""
return self.redis_client.get(key)
def set(self, key: str, value):
"""Set a key-value pair in Redis"""
return self.redis_client.set(key, value)
def rpush(self, key: str, value):
"""Append a value to a Redis list"""
return self.redis_client.rpush(key, value)
def lindex(self, key: str, index: int):
"""Get an element from a Redis list by its index"""
return self.redis_client.lindex(key, index)
def spop(self, key: str, value):
"""Remove and return a random member from a Redis set"""
return self.redis_client.spop(key, value)
def get_all_tasks(self):
"""Get all keys matching the task prefix pattern"""
return self.redis_client.lrange(ConfigServices.MAIN_TASK_PREFIX, 0, -1)
def ensure_connection(self) -> bool:
"""Check if Redis connection is alive and reconnect if needed"""
if not self.redis_connected:
try:
self.redis_client = self._create_redis_client()
self.redis_connected = self._check_redis_connection()
if self.redis_connected:
logger.info("Redis connection re-established successfully")
return self.redis_connected
except Exception as e:
logger.error(f"Failed to re-establish Redis connection: {str(e)}")
return False
return True
@classmethod
def handle_reconnection(cls, consecutive_errors=0, max_consecutive_errors=5):
"""
Handle Redis reconnection with exponential backoff based on consecutive errors
Args:
consecutive_errors: Number of consecutive errors encountered
max_consecutive_errors: Threshold for extended sleep time
Returns:
tuple: (RedisHandler instance, bool indicating if extended sleep is needed)
"""
try:
# Get a fresh instance (will reconnect internally)
instance = cls()
instance.redis_connected = instance._check_redis_connection()
logger.info("Recreated Redis handler using singleton pattern")
# Determine if extended sleep is needed
need_extended_sleep = consecutive_errors >= max_consecutive_errors
if need_extended_sleep:
logger.warning(f"Hit {max_consecutive_errors} consecutive Redis errors, taking longer pause")
return instance, need_extended_sleep
except Exception as redis_retry_error:
logger.error(f"Failed to recreate Redis handler: {str(redis_retry_error)}")
return None, consecutive_errors >= max_consecutive_errors