load: Optionally disable reading secrets from env (langchain-ai#19596)

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libs/core/langchain_core/load/load.py

@@ -29,7 +29,9 @@ def __init__(
         self,
         secrets_map: Optional[Dict[str, str]] = None,
         valid_namespaces: Optional[List[str]] = None,
+        secrets_from_env: bool = True,
     ) -> None:
+        self.secrets_from_env = secrets_from_env
         self.secrets_map = secrets_map or dict()
         # By default only support langchain, but user can pass in additional namespaces
         self.valid_namespaces = (
@@ -48,7 +50,7 @@ def __call__(self, value: Dict[str, Any]) -> Any:
             if key in self.secrets_map:
                 return self.secrets_map[key]
             else:
-                if key in os.environ and os.environ[key]:
+                if self.secrets_from_env and key in os.environ and os.environ[key]:
                     return os.environ[key]
                 raise KeyError(f'Missing key "{key}" in load(secrets_map)')
 
@@ -116,6 +118,7 @@ def loads(
     *,
     secrets_map: Optional[Dict[str, str]] = None,
     valid_namespaces: Optional[List[str]] = None,
+    secrets_from_env: bool = True,
 ) -> Any:
     """Revive a LangChain class from a JSON string.
     Equivalent to `load(json.loads(text))`.
@@ -129,7 +132,9 @@ def loads(
     Returns:
         Revived LangChain objects.
     """
-    return json.loads(text, object_hook=Reviver(secrets_map, valid_namespaces))
+    return json.loads(
+        text, object_hook=Reviver(secrets_map, valid_namespaces, secrets_from_env)
+    )
 
 
 @beta()
@@ -138,6 +143,7 @@ def load(
     *,
     secrets_map: Optional[Dict[str, str]] = None,
     valid_namespaces: Optional[List[str]] = None,
+    secrets_from_env: bool = True,
 ) -> Any:
     """Revive a LangChain class from a JSON object. Use this if you already
     have a parsed JSON object, eg. from `json.load` or `orjson.loads`.
@@ -151,7 +157,7 @@ def load(
     Returns:
         Revived LangChain objects.
     """
-    reviver = Reviver(secrets_map, valid_namespaces)
+    reviver = Reviver(secrets_map, valid_namespaces, secrets_from_env)
 
     def _load(obj: Any) -> Any:
         if isinstance(obj, dict):