dify/api/extensions/ext_redis.py

86 lines
2.9 KiB
Python

import redis
from redis.connection import Connection, SSLConnection
from redis.sentinel import Sentinel
from configs import dify_config
class RedisClientWrapper(redis.Redis):
"""
A wrapper class for the Redis client that addresses the issue where the global
`redis_client` variable cannot be updated when a new Redis instance is returned
by Sentinel.
This class allows for deferred initialization of the Redis client, enabling the
client to be re-initialized with a new instance when necessary. This is particularly
useful in scenarios where the Redis instance may change dynamically, such as during
a failover in a Sentinel-managed Redis setup.
Attributes:
_client (redis.Redis): The actual Redis client instance. It remains None until
initialized with the `initialize` method.
Methods:
initialize(client): Initializes the Redis client if it hasn't been initialized already.
__getattr__(item): Delegates attribute access to the Redis client, raising an error
if the client is not initialized.
"""
def __init__(self):
self._client = None
def initialize(self, client):
if self._client is None:
self._client = client
def __getattr__(self, item):
if self._client is None:
raise RuntimeError("Redis client is not initialized. Call init_app first.")
return getattr(self._client, item)
redis_client = RedisClientWrapper()
def init_app(app):
global redis_client
connection_class = Connection
if dify_config.REDIS_USE_SSL:
connection_class = SSLConnection
redis_params = {
"username": dify_config.REDIS_USERNAME,
"password": dify_config.REDIS_PASSWORD,
"db": dify_config.REDIS_DB,
"encoding": "utf-8",
"encoding_errors": "strict",
"decode_responses": False,
}
if dify_config.REDIS_USE_SENTINEL:
sentinel_hosts = [
(node.split(":")[0], int(node.split(":")[1])) for node in dify_config.REDIS_SENTINELS.split(",")
]
sentinel = Sentinel(
sentinel_hosts,
sentinel_kwargs={
"socket_timeout": dify_config.REDIS_SENTINEL_SOCKET_TIMEOUT,
"username": dify_config.REDIS_SENTINEL_USERNAME,
"password": dify_config.REDIS_SENTINEL_PASSWORD,
},
)
master = sentinel.master_for(dify_config.REDIS_SENTINEL_SERVICE_NAME, **redis_params)
redis_client.initialize(master)
else:
redis_params.update(
{
"host": dify_config.REDIS_HOST,
"port": dify_config.REDIS_PORT,
"connection_class": connection_class,
}
)
pool = redis.ConnectionPool(**redis_params)
redis_client.initialize(redis.Redis(connection_pool=pool))
app.extensions["redis"] = redis_client