Add serializer name to cache key to avoid errors due to switching serializers

2 files changed, 4 insertions, 6 deletions

diff --git a/requests_cache/backends/base.py b/requests_cache/backends/base.py
index 7f44af4..a8b1be3 100644
--- a/requests_cache/backends/base.py
+++ b/requests_cache/backends/base.py
@@ -109,6 +109,7 @@ class BaseCache:
             request=request,
             ignored_parameters=self._settings.ignored_parameters,
             match_headers=self._settings.match_headers,
+            serializer=self.responses.serializer,
             **kwargs,
         )
 
@@ -290,6 +291,7 @@ class DictStorage(UserDict, BaseStorage):
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         self._serializer = None
+        self.serializer = None
 
     def __getitem__(self, key):
         """An additional step is needed here for response data. Since the original response object
diff --git a/requests_cache/backends/mongodb.py b/requests_cache/backends/mongodb.py
index cd39f49..12d11d9 100644
--- a/requests_cache/backends/mongodb.py
+++ b/requests_cache/backends/mongodb.py
@@ -104,16 +104,12 @@ from pymongo.errors import OperationFailure
 
 from .._utils import get_valid_kwargs
 from ..expiration import NEVER_EXPIRE, get_expiration_seconds
-from ..serializers import SerializerPipeline
-from ..serializers.preconf import bson_preconf_stage
+from ..serializers import bson_document_serializer
 from . import BaseCache, BaseStorage
 
-document_serializer = SerializerPipeline([bson_preconf_stage], is_binary=False)
 logger = getLogger(__name__)
 
 
-# TODO: Is there any reason to support custom serializers here?
-# TODO: Save items with different cache keys to avoid conflicts with old serialization format?
 class MongoCache(BaseCache):
     """MongoDB cache backend
 
@@ -239,7 +235,7 @@ class MongoPickleDict(MongoDict):
     """
 
     def __init__(self, *args, serializer=None, **kwargs):
-        super().__init__(*args, serializer=serializer or document_serializer, **kwargs)
+        super().__init__(*args, serializer=serializer or bson_document_serializer, **kwargs)
 
     def __getitem__(self, key):
         return self.serializer.loads(super().__getitem__(key))