Robustly test if Redis clients talk to the same db (#560)

* Robustly test if Redis clients talk to the same db

Previously, we were comparing the two clients' `connection_kwargs`, but
`connection_kwargs` contains more than just `host`, `port`, and `db`:

```python
>>> from redis import Redis
>>> redis = Redis()
>>> redis.connection_pool.connection_kwargs
{'db': 0, 'username': None, 'password': None, 'socket_timeout': None, 'encoding': 'utf-8', 'encoding_errors': 'strict', 'decode_responses': False, 'retry_on_error': [], 'retry': None, 'health_check_interval': 0, 'client_name': None, 'redis_connect_func': None, 'host': 'localhost', 'port': 6379, 'socket_connect_timeout': None, 'socket_keepalive': None, 'socket_keepalive_options': None}
```

This PR allows Pottery to recognize that two Redis clients are connected
to the same database even if their socket timeout our retry policies are
different.

* Bump version number

pottery/__init__.py

@@ -32,7 +32,7 @@
 
 
 __title__: Final[str] = 'pottery'
-__version__: Final[str] = '2.3.0'
+__version__: Final[str] = '2.3.1'
 __description__: Final[str] = __doc__.split(sep='\n\n', maxsplit=1)[0]
 __url__: Final[str] = 'https://github.com/brainix/pottery'
 __author__: Final[str] = 'Rajiv Bakulesh Shah'

pottery/base.py

@@ -81,6 +81,14 @@ def random_key(*,
     return key
 
 
+def connection_args(redis: Redis) -> Tuple[str, int, int]:
+    return (
+        redis.connection_pool.connection_kwargs['host'],
+        redis.connection_pool.connection_kwargs.get('port', 6379),
+        redis.connection_pool.connection_kwargs.get('db', 0),
+    )
+
+
 class _Common:
     'Mixin class that implements self.redis and self.key properties.'
 
@@ -213,12 +221,7 @@ def __context_managers(self,
         redises = collections.defaultdict(list)
         for container in (self, *others):
             if isinstance(container, _Pipelined):
-                connection_kwargs = (
-                    container.redis.connection_pool.connection_kwargs['host'],
-                    container.redis.connection_pool.connection_kwargs.get('port', 6379),
-                    container.redis.connection_pool.connection_kwargs.get('db', 0),
-                )
-                redises[connection_kwargs].append(container)
+                redises[connection_args(container.redis)].append(container)
         for containers in redises.values():
             keys = (container.key for container in containers)
             pipeline = containers[0].__watch_keys(*keys)
@@ -262,7 +265,7 @@ def _same_redis(self, *others: Any) -> bool:
         for other in others:
             if not isinstance(other, _Comparable):
                 return False
-            if self.redis.connection_pool != other.redis.connection_pool:
+            if connection_args(self.redis) != connection_args(other.redis):
                 return False
         return True
 

pottery/hyper.py

@@ -36,6 +36,7 @@
 from .annotations import RedisValues
 from .base import Base
 from .base import JSONTypes
+from .base import connection_args
 from .base import random_key
 
 
@@ -131,7 +132,7 @@ def update(self,
         with self._watch(objs) as pipeline:
             for obj in objs:
                 if isinstance(obj, self.__class__):
-                    if self.redis.connection_pool != obj.redis.connection_pool:
+                    if connection_args(self.redis) != connection_args(obj.redis):
                         raise RuntimeError(
                             f"can't update {self} with {obj} as they live on "
                             "different Redis instances/databases"

pottery/monkey.py

@@ -31,28 +31,6 @@
 _logger: Final[logging.Logger] = logging.getLogger('pottery')
 
 
-# The Redis client connection pool doesn't have a sane equality test.  So
-# monkey patch equality comparisons on to the connection pool.  We consider two
-# connection pools to be equal if they're connected to the same host, port, and
-# database.
-
-from redis import ConnectionPool  # isort: skip
-
-def __eq__(self: ConnectionPool, other: Any) -> bool:
-    try:
-        value: bool = self.connection_kwargs == other.connection_kwargs
-    except AttributeError:  # pragma: no cover
-        value = False
-    return value
-
-ConnectionPool.__eq__ = __eq__  # type: ignore
-
-_logger.info(
-    'Monkey patched redis.ConnectionPool.__eq__() to compare Redis clients by '
-    'connection params'
-)
-
-
 # Monkey patch the JSON encoder to be able to JSONify any instance of any class
 # that defines a to_dict(), to_list(), or to_str() method (since the encoder
 # already knows how to JSONify dicts, lists, and strings).