community[minor]: Allow passing allow_dangerous_deserialization when loading LLM chain (#18894)

### Issue
Recently, the new `allow_dangerous_deserialization` flag was introduced
for preventing unsafe model deserialization that relies on pickle
without user's notice (#18696). Since then some LLMs like Databricks
requires passing in this flag with true to instantiate the model.

However, this breaks existing functionality to loading such LLMs within
a chain using `load_chain` method, because the underlying loader
function
[load_llm_from_config](f96dd57501/libs/langchain/langchain/chains/loading.py (L40))
 (and load_llm) ignores keyword arguments passed in. 

### Solution
This PR fixes this issue by propagating the
`allow_dangerous_deserialization` argument to the class loader iff the
LLM class has that field.

---------

Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>
Co-authored-by: Bagatur <22008038+baskaryan@users.noreply.github.com>

libs/community/langchain_community/llms/loading.py

@@ -1,15 +1,17 @@
 """Base interface for loading large language model APIs."""
 import json
 from pathlib import Path
-from typing import Union
+from typing import Any, Union
 
 import yaml
 from langchain_core.language_models.llms import BaseLLM
 
 from langchain_community.llms import get_type_to_cls_dict
 
+_ALLOW_DANGEROUS_DESERIALIZATION_ARG = "allow_dangerous_deserialization"
 
-def load_llm_from_config(config: dict) -> BaseLLM:
+
+def load_llm_from_config(config: dict, **kwargs: Any) -> BaseLLM:
     """Load LLM from Config Dict."""
     if "_type" not in config:
         raise ValueError("Must specify an LLM Type in config")
@@ -21,11 +23,17 @@ def load_llm_from_config(config: dict) -> BaseLLM:
         raise ValueError(f"Loading {config_type} LLM not supported")
 
     llm_cls = type_to_cls_dict[config_type]()
-    return llm_cls(**config)
+
+    load_kwargs = {}
+    if _ALLOW_DANGEROUS_DESERIALIZATION_ARG in llm_cls.__fields__:
+        load_kwargs[_ALLOW_DANGEROUS_DESERIALIZATION_ARG] = kwargs.get(
+            _ALLOW_DANGEROUS_DESERIALIZATION_ARG, False
+        )
+
+    return llm_cls(**config, **load_kwargs)
 
 
-def load_llm(file: Union[str, Path]) -> BaseLLM:
+def load_llm(file: Union[str, Path], **kwargs: Any) -> BaseLLM:
-    """Load LLM from file."""
     # Convert file to Path object.
     if isinstance(file, str):
         file_path = Path(file)
@@ -41,4 +49,4 @@ def load_llm(file: Union[str, Path]) -> BaseLLM:
     else:
         raise ValueError("File type must be json or yaml")
     # Load the LLM from the config now.
-    return load_llm_from_config(config)
+    return load_llm_from_config(config, **kwargs)

libs/community/tests/unit_tests/llms/test_databricks.py

@@ -1,4 +1,5 @@
 """test Databricks LLM"""
+from pathlib import Path
 from typing import Any, Dict
 
 import pytest
@@ -8,6 +9,8 @@ from langchain_community.llms.databricks import (
     Databricks,
     _load_pickled_fn_from_hex_string,
 )
+from langchain_community.llms.loading import load_llm
+from tests.integration_tests.llms.utils import assert_llm_equality
 
 
 class MockDatabricksServingEndpointClient:
@@ -55,3 +58,26 @@ def test_serde_transform_input_fn(monkeypatch: MonkeyPatch) -> None:
     request = {"prompt": "What is the meaning of life?"}
     fn = _load_pickled_fn_from_hex_string(params["transform_input_fn"])
     assert fn(**request) == transform_input(**request)
+
+
+def test_saving_loading_llm(monkeypatch: MonkeyPatch, tmp_path: Path) -> None:
+    monkeypatch.setattr(
+        "langchain_community.llms.databricks._DatabricksServingEndpointClient",
+        MockDatabricksServingEndpointClient,
+    )
+    monkeypatch.setenv("DATABRICKS_HOST", "my-default-host")
+    monkeypatch.setenv("DATABRICKS_TOKEN", "my-default-token")
+
+    llm = Databricks(
+        endpoint_name="chat", temperature=0.1, allow_dangerous_deserialization=True
+    )
+    llm.save(file_path=tmp_path / "databricks.yaml")
+
+    # Loading without allowing_dangerous_deserialization=True should raise an error.
+    with pytest.raises(ValueError, match="This code relies on the pickle module."):
+        load_llm(tmp_path / "databricks.yaml")
+
+    loaded_llm = load_llm(
+        tmp_path / "databricks.yaml", allow_dangerous_deserialization=True
+    )
+    assert_llm_equality(llm, loaded_llm)

libs/langchain/langchain/chains/loading.py

@@ -37,9 +37,9 @@ def _load_llm_chain(config: dict, **kwargs: Any) -> LLMChain:
     """Load LLM chain from config dict."""
     if "llm" in config:
         llm_config = config.pop("llm")
-        llm = load_llm_from_config(llm_config)
+        llm = load_llm_from_config(llm_config, **kwargs)
     elif "llm_path" in config:
-        llm = load_llm(config.pop("llm_path"))
+        llm = load_llm(config.pop("llm_path"), **kwargs)
     else:
         raise ValueError("One of `llm` or `llm_path` must be present.")
 
@@ -59,9 +59,9 @@ def _load_hyde_chain(config: dict, **kwargs: Any) -> HypotheticalDocumentEmbedde
     """Load hypothetical document embedder chain from config dict."""
     if "llm_chain" in config:
         llm_chain_config = config.pop("llm_chain")
-        llm_chain = load_chain_from_config(llm_chain_config)
+        llm_chain = load_chain_from_config(llm_chain_config, **kwargs)
     elif "llm_chain_path" in config:
-        llm_chain = load_chain(config.pop("llm_chain_path"))
+        llm_chain = load_chain(config.pop("llm_chain_path"), **kwargs)
     else:
         raise ValueError("One of `llm_chain` or `llm_chain_path` must be present.")
     if "embeddings" in kwargs:
@@ -78,9 +78,9 @@ def _load_hyde_chain(config: dict, **kwargs: Any) -> HypotheticalDocumentEmbedde
 def _load_stuff_documents_chain(config: dict, **kwargs: Any) -> StuffDocumentsChain:
     if "llm_chain" in config:
         llm_chain_config = config.pop("llm_chain")
-        llm_chain = load_chain_from_config(llm_chain_config)
+        llm_chain = load_chain_from_config(llm_chain_config, **kwargs)
     elif "llm_chain_path" in config:
-        llm_chain = load_chain(config.pop("llm_chain_path"))
+        llm_chain = load_chain(config.pop("llm_chain_path"), **kwargs)
     else:
         raise ValueError("One of `llm_chain` or `llm_chain_path` must be present.")
 
@@ -107,9 +107,9 @@ def _load_map_reduce_documents_chain(
 ) -> MapReduceDocumentsChain:
     if "llm_chain" in config:
         llm_chain_config = config.pop("llm_chain")
-        llm_chain = load_chain_from_config(llm_chain_config)
+        llm_chain = load_chain_from_config(llm_chain_config, **kwargs)
     elif "llm_chain_path" in config:
-        llm_chain = load_chain(config.pop("llm_chain_path"))
+        llm_chain = load_chain(config.pop("llm_chain_path"), **kwargs)
     else:
         raise ValueError("One of `llm_chain` or `llm_chain_path` must be present.")
 
@@ -118,12 +118,14 @@ def _load_map_reduce_documents_chain(
 
     if "reduce_documents_chain" in config:
         reduce_documents_chain = load_chain_from_config(
-            config.pop("reduce_documents_chain")
+            config.pop("reduce_documents_chain"), **kwargs
         )
     elif "reduce_documents_chain_path" in config:
-        reduce_documents_chain = load_chain(config.pop("reduce_documents_chain_path"))
+        reduce_documents_chain = load_chain(
+            config.pop("reduce_documents_chain_path"), **kwargs
+        )
     else:
-        reduce_documents_chain = _load_reduce_documents_chain(config)
+        reduce_documents_chain = _load_reduce_documents_chain(config, **kwargs)
 
     return MapReduceDocumentsChain(
         llm_chain=llm_chain,
@@ -138,14 +140,22 @@ def _load_reduce_documents_chain(config: dict, **kwargs: Any) -> ReduceDocuments
 
     if "combine_documents_chain" in config:
         combine_document_chain_config = config.pop("combine_documents_chain")
-        combine_documents_chain = load_chain_from_config(combine_document_chain_config)
+        combine_documents_chain = load_chain_from_config(
+            combine_document_chain_config, **kwargs
+        )
     elif "combine_document_chain" in config:
         combine_document_chain_config = config.pop("combine_document_chain")
-        combine_documents_chain = load_chain_from_config(combine_document_chain_config)
+        combine_documents_chain = load_chain_from_config(
+            combine_document_chain_config, **kwargs
+        )
     elif "combine_documents_chain_path" in config:
-        combine_documents_chain = load_chain(config.pop("combine_documents_chain_path"))
+        combine_documents_chain = load_chain(
+            config.pop("combine_documents_chain_path"), **kwargs
+        )
     elif "combine_document_chain_path" in config:
-        combine_documents_chain = load_chain(config.pop("combine_document_chain_path"))
+        combine_documents_chain = load_chain(
+            config.pop("combine_document_chain_path"), **kwargs
+        )
     else:
         raise ValueError(
             "One of `combine_documents_chain` or "
@@ -158,11 +168,11 @@ def _load_reduce_documents_chain(config: dict, **kwargs: Any) -> ReduceDocuments
             collapse_documents_chain = None
         else:
             collapse_documents_chain = load_chain_from_config(
-                collapse_document_chain_config
+                collapse_document_chain_config, **kwargs
             )
     elif "collapse_documents_chain_path" in config:
         collapse_documents_chain = load_chain(
-            config.pop("collapse_documents_chain_path")
+            config.pop("collapse_documents_chain_path"), **kwargs
         )
     elif "collapse_document_chain" in config:
         collapse_document_chain_config = config.pop("collapse_document_chain")
@@ -170,11 +180,11 @@ def _load_reduce_documents_chain(config: dict, **kwargs: Any) -> ReduceDocuments
             collapse_documents_chain = None
         else:
             collapse_documents_chain = load_chain_from_config(
-                collapse_document_chain_config
+                collapse_document_chain_config, **kwargs
             )
     elif "collapse_document_chain_path" in config:
         collapse_documents_chain = load_chain(
-            config.pop("collapse_document_chain_path")
+            config.pop("collapse_document_chain_path"), **kwargs
         )
 
     return ReduceDocumentsChain(
@@ -190,17 +200,17 @@ def _load_llm_bash_chain(config: dict, **kwargs: Any) -> Any:
     llm_chain = None
     if "llm_chain" in config:
         llm_chain_config = config.pop("llm_chain")
-        llm_chain = load_chain_from_config(llm_chain_config)
+        llm_chain = load_chain_from_config(llm_chain_config, **kwargs)
     elif "llm_chain_path" in config:
-        llm_chain = load_chain(config.pop("llm_chain_path"))
+        llm_chain = load_chain(config.pop("llm_chain_path"), **kwargs)
     # llm attribute is deprecated in favor of llm_chain, here to support old configs
     elif "llm" in config:
         llm_config = config.pop("llm")
-        llm = load_llm_from_config(llm_config)
+        llm = load_llm_from_config(llm_config, **kwargs)
     # llm_path attribute is deprecated in favor of llm_chain_path,
     # its to support old configs
     elif "llm_path" in config:
-        llm = load_llm(config.pop("llm_path"))
+        llm = load_llm(config.pop("llm_path"), **kwargs)
     else:
         raise ValueError("One of `llm_chain` or `llm_chain_path` must be present.")
     if "prompt" in config:
@@ -217,9 +227,9 @@ def _load_llm_bash_chain(config: dict, **kwargs: Any) -> Any:
 def _load_llm_checker_chain(config: dict, **kwargs: Any) -> LLMCheckerChain:
     if "llm" in config:
         llm_config = config.pop("llm")
-        llm = load_llm_from_config(llm_config)
+        llm = load_llm_from_config(llm_config, **kwargs)
     elif "llm_path" in config:
-        llm = load_llm(config.pop("llm_path"))
+        llm = load_llm(config.pop("llm_path"), **kwargs)
     else:
         raise ValueError("One of `llm` or `llm_path` must be present.")
     if "create_draft_answer_prompt" in config:
@@ -264,17 +274,17 @@ def _load_llm_math_chain(config: dict, **kwargs: Any) -> LLMMathChain:
     llm_chain = None
     if "llm_chain" in config:
         llm_chain_config = config.pop("llm_chain")
-        llm_chain = load_chain_from_config(llm_chain_config)
+        llm_chain = load_chain_from_config(llm_chain_config, **kwargs)
     elif "llm_chain_path" in config:
-        llm_chain = load_chain(config.pop("llm_chain_path"))
+        llm_chain = load_chain(config.pop("llm_chain_path"), **kwargs)
     # llm attribute is deprecated in favor of llm_chain, here to support old configs
     elif "llm" in config:
         llm_config = config.pop("llm")
-        llm = load_llm_from_config(llm_config)
+        llm = load_llm_from_config(llm_config, **kwargs)
     # llm_path attribute is deprecated in favor of llm_chain_path,
     # its to support old configs
     elif "llm_path" in config:
-        llm = load_llm(config.pop("llm_path"))
+        llm = load_llm(config.pop("llm_path"), **kwargs)
     else:
         raise ValueError("One of `llm_chain` or `llm_chain_path` must be present.")
     if "prompt" in config:
@@ -293,9 +303,9 @@ def _load_map_rerank_documents_chain(
 ) -> MapRerankDocumentsChain:
     if "llm_chain" in config:
         llm_chain_config = config.pop("llm_chain")
-        llm_chain = load_chain_from_config(llm_chain_config)
+        llm_chain = load_chain_from_config(llm_chain_config, **kwargs)
     elif "llm_chain_path" in config:
-        llm_chain = load_chain(config.pop("llm_chain_path"))
+        llm_chain = load_chain(config.pop("llm_chain_path"), **kwargs)
     else:
         raise ValueError("One of `llm_chain` or `llm_chain_path` must be present.")
     return MapRerankDocumentsChain(llm_chain=llm_chain, **config)  # type: ignore[arg-type]
@@ -306,9 +316,9 @@ def _load_pal_chain(config: dict, **kwargs: Any) -> Any:
 
     if "llm_chain" in config:
         llm_chain_config = config.pop("llm_chain")
-        llm_chain = load_chain_from_config(llm_chain_config)
+        llm_chain = load_chain_from_config(llm_chain_config, **kwargs)
     elif "llm_chain_path" in config:
-        llm_chain = load_chain(config.pop("llm_chain_path"))
+        llm_chain = load_chain(config.pop("llm_chain_path"), **kwargs)
     else:
         raise ValueError("One of `llm_chain` or `llm_chain_path` must be present.")
     return PALChain(llm_chain=llm_chain, **config)  # type: ignore[arg-type]
@@ -317,18 +327,18 @@ def _load_pal_chain(config: dict, **kwargs: Any) -> Any:
 def _load_refine_documents_chain(config: dict, **kwargs: Any) -> RefineDocumentsChain:
     if "initial_llm_chain" in config:
         initial_llm_chain_config = config.pop("initial_llm_chain")
-        initial_llm_chain = load_chain_from_config(initial_llm_chain_config)
+        initial_llm_chain = load_chain_from_config(initial_llm_chain_config, **kwargs)
     elif "initial_llm_chain_path" in config:
-        initial_llm_chain = load_chain(config.pop("initial_llm_chain_path"))
+        initial_llm_chain = load_chain(config.pop("initial_llm_chain_path"), **kwargs)
     else:
         raise ValueError(
             "One of `initial_llm_chain` or `initial_llm_chain_path` must be present."
         )
     if "refine_llm_chain" in config:
         refine_llm_chain_config = config.pop("refine_llm_chain")
-        refine_llm_chain = load_chain_from_config(refine_llm_chain_config)
+        refine_llm_chain = load_chain_from_config(refine_llm_chain_config, **kwargs)
     elif "refine_llm_chain_path" in config:
-        refine_llm_chain = load_chain(config.pop("refine_llm_chain_path"))
+        refine_llm_chain = load_chain(config.pop("refine_llm_chain_path"), **kwargs)
     else:
         raise ValueError(
             "One of `refine_llm_chain` or `refine_llm_chain_path` must be present."
@@ -349,9 +359,13 @@ def _load_refine_documents_chain(config: dict, **kwargs: Any) -> RefineDocuments
 def _load_qa_with_sources_chain(config: dict, **kwargs: Any) -> QAWithSourcesChain:
     if "combine_documents_chain" in config:
         combine_documents_chain_config = config.pop("combine_documents_chain")
-        combine_documents_chain = load_chain_from_config(combine_documents_chain_config)
+        combine_documents_chain = load_chain_from_config(
+            combine_documents_chain_config, **kwargs
+        )
     elif "combine_documents_chain_path" in config:
-        combine_documents_chain = load_chain(config.pop("combine_documents_chain_path"))
+        combine_documents_chain = load_chain(
+            config.pop("combine_documents_chain_path"), **kwargs
+        )
     else:
         raise ValueError(
             "One of `combine_documents_chain` or "
@@ -369,13 +383,13 @@ def _load_sql_database_chain(config: dict, **kwargs: Any) -> Any:
         raise ValueError("`database` must be present.")
     if "llm_chain" in config:
         llm_chain_config = config.pop("llm_chain")
-        chain = load_chain_from_config(llm_chain_config)
+        chain = load_chain_from_config(llm_chain_config, **kwargs, **kwargs)
-        return SQLDatabaseChain(llm_chain=chain, database=database, **config)  # type: ignore[arg-type]
+        return SQLDatabaseChain(llm_chain=chain, database=database, **config)
     if "llm" in config:
         llm_config = config.pop("llm")
-        llm = load_llm_from_config(llm_config)
+        llm = load_llm_from_config(llm_config, **kwargs)
     elif "llm_path" in config:
-        llm = load_llm(config.pop("llm_path"))
+        llm = load_llm(config.pop("llm_path"), **kwargs)
     else:
         raise ValueError("One of `llm` or `llm_path` must be present.")
     if "prompt" in config:
@@ -396,9 +410,13 @@ def _load_vector_db_qa_with_sources_chain(
         raise ValueError("`vectorstore` must be present.")
     if "combine_documents_chain" in config:
         combine_documents_chain_config = config.pop("combine_documents_chain")
-        combine_documents_chain = load_chain_from_config(combine_documents_chain_config)
+        combine_documents_chain = load_chain_from_config(
+            combine_documents_chain_config, **kwargs
+        )
     elif "combine_documents_chain_path" in config:
-        combine_documents_chain = load_chain(config.pop("combine_documents_chain_path"))
+        combine_documents_chain = load_chain(
+            config.pop("combine_documents_chain_path"), **kwargs
+        )
     else:
         raise ValueError(
             "One of `combine_documents_chain` or "
@@ -418,9 +436,13 @@ def _load_retrieval_qa(config: dict, **kwargs: Any) -> RetrievalQA:
         raise ValueError("`retriever` must be present.")
     if "combine_documents_chain" in config:
         combine_documents_chain_config = config.pop("combine_documents_chain")
-        combine_documents_chain = load_chain_from_config(combine_documents_chain_config)
+        combine_documents_chain = load_chain_from_config(
+            combine_documents_chain_config, **kwargs
+        )
     elif "combine_documents_chain_path" in config:
-        combine_documents_chain = load_chain(config.pop("combine_documents_chain_path"))
+        combine_documents_chain = load_chain(
+            config.pop("combine_documents_chain_path"), **kwargs
+        )
     else:
         raise ValueError(
             "One of `combine_documents_chain` or "
@@ -442,9 +464,13 @@ def _load_retrieval_qa_with_sources_chain(
         raise ValueError("`retriever` must be present.")
     if "combine_documents_chain" in config:
         combine_documents_chain_config = config.pop("combine_documents_chain")
-        combine_documents_chain = load_chain_from_config(combine_documents_chain_config)
+        combine_documents_chain = load_chain_from_config(
+            combine_documents_chain_config, **kwargs
+        )
     elif "combine_documents_chain_path" in config:
-        combine_documents_chain = load_chain(config.pop("combine_documents_chain_path"))
+        combine_documents_chain = load_chain(
+            config.pop("combine_documents_chain_path"), **kwargs
+        )
     else:
         raise ValueError(
             "One of `combine_documents_chain` or "
@@ -464,9 +490,13 @@ def _load_vector_db_qa(config: dict, **kwargs: Any) -> VectorDBQA:
         raise ValueError("`vectorstore` must be present.")
     if "combine_documents_chain" in config:
         combine_documents_chain_config = config.pop("combine_documents_chain")
-        combine_documents_chain = load_chain_from_config(combine_documents_chain_config)
+        combine_documents_chain = load_chain_from_config(
+            combine_documents_chain_config, **kwargs
+        )
     elif "combine_documents_chain_path" in config:
-        combine_documents_chain = load_chain(config.pop("combine_documents_chain_path"))
+        combine_documents_chain = load_chain(
+            config.pop("combine_documents_chain_path"), **kwargs
+        )
     else:
         raise ValueError(
             "One of `combine_documents_chain` or "
@@ -486,12 +516,14 @@ def _load_graph_cypher_chain(config: dict, **kwargs: Any) -> GraphCypherQAChain:
         raise ValueError("`graph` must be present.")
     if "cypher_generation_chain" in config:
         cypher_generation_chain_config = config.pop("cypher_generation_chain")
-        cypher_generation_chain = load_chain_from_config(cypher_generation_chain_config)
+        cypher_generation_chain = load_chain_from_config(
+            cypher_generation_chain_config, **kwargs
+        )
     else:
         raise ValueError("`cypher_generation_chain` must be present.")
     if "qa_chain" in config:
         qa_chain_config = config.pop("qa_chain")
-        qa_chain = load_chain_from_config(qa_chain_config)
+        qa_chain = load_chain_from_config(qa_chain_config, **kwargs)
     else:
         raise ValueError("`qa_chain` must be present.")
 
@@ -506,7 +538,7 @@ def _load_graph_cypher_chain(config: dict, **kwargs: Any) -> GraphCypherQAChain:
 def _load_api_chain(config: dict, **kwargs: Any) -> APIChain:
     if "api_request_chain" in config:
         api_request_chain_config = config.pop("api_request_chain")
-        api_request_chain = load_chain_from_config(api_request_chain_config)
+        api_request_chain = load_chain_from_config(api_request_chain_config, **kwargs)
     elif "api_request_chain_path" in config:
         api_request_chain = load_chain(config.pop("api_request_chain_path"))
     else:
@@ -515,9 +547,9 @@ def _load_api_chain(config: dict, **kwargs: Any) -> APIChain:
         )
     if "api_answer_chain" in config:
         api_answer_chain_config = config.pop("api_answer_chain")
-        api_answer_chain = load_chain_from_config(api_answer_chain_config)
+        api_answer_chain = load_chain_from_config(api_answer_chain_config, **kwargs)
     elif "api_answer_chain_path" in config:
-        api_answer_chain = load_chain(config.pop("api_answer_chain_path"))
+        api_answer_chain = load_chain(config.pop("api_answer_chain_path"), **kwargs)
     else:
         raise ValueError(
             "One of `api_answer_chain` or `api_answer_chain_path` must be present."
@@ -537,9 +569,9 @@ def _load_api_chain(config: dict, **kwargs: Any) -> APIChain:
 def _load_llm_requests_chain(config: dict, **kwargs: Any) -> LLMRequestsChain:
     if "llm_chain" in config:
         llm_chain_config = config.pop("llm_chain")
-        llm_chain = load_chain_from_config(llm_chain_config)
+        llm_chain = load_chain_from_config(llm_chain_config, **kwargs)
     elif "llm_chain_path" in config:
-        llm_chain = load_chain(config.pop("llm_chain_path"))
+        llm_chain = load_chain(config.pop("llm_chain_path"), **kwargs)
     else:
         raise ValueError("One of `llm_chain` or `llm_chain_path` must be present.")
     if "requests_wrapper" in kwargs: