🐛 fix(cache/manager.py): unpickle cached value before returning it to fix deserialization issue

🐛 fix(cache/manager.py): pickle value before caching it to mimic Redis behavior
🐛 fix(cache/manager.py): raise ValueError if RedisCache fails to set the value
🐛 fix(session/manager.py): generate key if it is None before checking cache
✨ feat(session/manager.py): add logging import to enable logging in the session manager

src/backend/langflow/services/cache/manager.py

@@ -72,7 +72,8 @@ class InMemoryCache(BaseCacheService, Service):
             ):
                 # Move the key to the end to make it recently used
                 self._cache.move_to_end(key)
-                return item["value"]
+                unpickled = pickle.loads(item["value"])
+                return unpickled
             else:
                 self.delete(key)
         return None
@@ -94,7 +95,9 @@ class InMemoryCache(BaseCacheService, Service):
             elif self.max_size and len(self._cache) >= self.max_size:
                 # Remove least recently used item
                 self._cache.popitem(last=False)
-            self._cache[key] = {"value": value, "time": time.time()}
+            # pickle locally to mimic Redis
+            pickled = pickle.dumps(value)
+            self._cache[key] = {"value": pickled, "time": time.time()}
 
     def upsert(self, key, value):
         """
@@ -257,7 +260,10 @@ class RedisCache(BaseCacheService, Service):
             value: The value to cache.
         """
         try:
-            self._client.setex(key, self.expiration_time, pickle.dumps(value))
+            if pickled := pickle.dumps(value):
+                result = self._client.setex(key, self.expiration_time, pickled)
+                if not result:
+                    raise ValueError("RedisCache could not set the value.")
         except TypeError as exc:
             raise TypeError(
                 "RedisCache only accepts values that can be pickled. "

src/backend/langflow/services/session/manager.py

@@ -2,7 +2,7 @@ from typing import TYPE_CHECKING
 from langflow.interface.run import build_sorted_vertices
 from langflow.services.base import Service
 from langflow.services.cache.utils import compute_dict_hash
-
+from loguru import logger
 from langflow.services.session.utils import session_id_generator
 
 if TYPE_CHECKING:
@@ -20,8 +20,12 @@ class SessionService(Service):
         if key in self.cache_service:
             return self.cache_service.get(key)
 
+        if key is None:
+            key = self.generate_key(session_id=None, data_graph=data_graph)
+
         # If not cached, build the graph and cache it
         graph, artifacts = build_sorted_vertices(data_graph)
+
         self.cache_service.set(key, (graph, artifacts))
 
         return graph, artifacts