Add support for passthrough auth for custom tool calls (#2824)

* Add support for passthrough auth for custom tool calls

* Fix formatting

backend/danswer/chat/process_message.py

@@ -105,6 +105,7 @@ from danswer.tools.tool import ToolResponse
 from danswer.tools.tool_runner import ToolCallFinalResult
 from danswer.tools.utils import compute_all_tool_tokens
 from danswer.tools.utils import explicit_tool_calling_supported
+from danswer.utils.headers import header_dict_to_header_list
 from danswer.utils.logger import setup_logger
 from danswer.utils.timing import log_generator_function_time
 
@@ -276,7 +277,7 @@ def stream_chat_message_objects(
     # on the `new_msg_req.message`. Currently, requires a state where the last message is a
     use_existing_user_message: bool = False,
     litellm_additional_headers: dict[str, str] | None = None,
-    tool_additional_headers: dict[str, str] | None = None,
+    custom_tool_additional_headers: dict[str, str] | None = None,
     is_connected: Callable[[], bool] | None = None,
     enforce_chat_session_id_for_search_docs: bool = True,
 ) -> ChatPacketStream:
@@ -640,7 +641,12 @@ def stream_chat_message_objects(
                             chat_session_id=chat_session_id,
                             message_id=user_message.id if user_message else None,
                         ),
-                        custom_headers=db_tool_model.custom_headers,
+                        custom_headers=(db_tool_model.custom_headers or [])
+                        + (
+                            header_dict_to_header_list(
+                                custom_tool_additional_headers or {}
+                            )
+                        ),
                     ),
                 )
 
@@ -863,7 +869,7 @@ def stream_chat_message(
     user: User | None,
     use_existing_user_message: bool = False,
     litellm_additional_headers: dict[str, str] | None = None,
-    tool_additional_headers: dict[str, str] | None = None,
+    custom_tool_additional_headers: dict[str, str] | None = None,
     is_connected: Callable[[], bool] | None = None,
 ) -> Iterator[str]:
     with get_session_context_manager() as db_session:
@@ -873,7 +879,7 @@ def stream_chat_message(
             db_session=db_session,
             use_existing_user_message=use_existing_user_message,
             litellm_additional_headers=litellm_additional_headers,
-            tool_additional_headers=tool_additional_headers,
+            custom_tool_additional_headers=custom_tool_additional_headers,
             is_connected=is_connected,
         )
         for obj in objects:

backend/danswer/configs/model_configs.py

@@ -119,19 +119,3 @@ if _LITELLM_PASS_THROUGH_HEADERS_RAW:
         logger.error(
             "Failed to parse LITELLM_PASS_THROUGH_HEADERS, must be a valid JSON object"
         )
-
-
-# List of headers to pass through to tool calls (e.g., API requests made by tools)
-# This allows for dynamic configuration of tool behavior based on incoming request headers
-TOOL_PASS_THROUGH_HEADERS: list[str] | None = None
-_TOOL_PASS_THROUGH_HEADERS_RAW = os.environ.get("TOOL_PASS_THROUGH_HEADERS")
-if _TOOL_PASS_THROUGH_HEADERS_RAW:
-    try:
-        TOOL_PASS_THROUGH_HEADERS = json.loads(_TOOL_PASS_THROUGH_HEADERS_RAW)
-    except Exception:
-        from danswer.utils.logger import setup_logger
-
-        logger = setup_logger()
-        logger.error(
-            "Failed to parse TOOL_PASS_THROUGH_HEADERS, must be a valid JSON object"
-        )

backend/danswer/configs/tool_configs.py

@@ -0,0 +1,22 @@
+import json
+import os
+
+
+# if specified, will pass through request headers to the call to API calls made by custom tools
+CUSTOM_TOOL_PASS_THROUGH_HEADERS: list[str] | None = None
+_CUSTOM_TOOL_PASS_THROUGH_HEADERS_RAW = os.environ.get(
+    "CUSTOM_TOOL_PASS_THROUGH_HEADERS"
+)
+if _CUSTOM_TOOL_PASS_THROUGH_HEADERS_RAW:
+    try:
+        CUSTOM_TOOL_PASS_THROUGH_HEADERS = json.loads(
+            _CUSTOM_TOOL_PASS_THROUGH_HEADERS_RAW
+        )
+    except Exception:
+        # need to import here to avoid circular imports
+        from danswer.utils.logger import setup_logger
+
+        logger = setup_logger()
+        logger.error(
+            "Failed to parse CUSTOM_TOOL_PASS_THROUGH_HEADERS, must be a valid JSON object"
+        )

backend/danswer/db/models.py

@@ -60,6 +60,7 @@ from danswer.llm.override_models import PromptOverride
 from danswer.search.enums import RecencyBiasSetting
 from danswer.utils.encryption import decrypt_bytes_to_string
 from danswer.utils.encryption import encrypt_string_to_bytes
+from danswer.utils.headers import HeaderItemDict
 from shared_configs.enums import EmbeddingProvider
 from shared_configs.enums import RerankerProvider
 
@@ -1288,7 +1289,7 @@ class Tool(Base):
     openapi_schema: Mapped[dict[str, Any] | None] = mapped_column(
         postgresql.JSONB(), nullable=True
     )
-    custom_headers: Mapped[list[dict[str, str]] | None] = mapped_column(
+    custom_headers: Mapped[list[HeaderItemDict] | None] = mapped_column(
         postgresql.JSONB(), nullable=True
     )
     # user who created / owns the tool. Will be None for built-in tools.

backend/danswer/db/tools.py

@@ -1,4 +1,5 @@
 from typing import Any
+from typing import cast
 from uuid import UUID
 
 from sqlalchemy import select
@@ -6,6 +7,7 @@ from sqlalchemy.orm import Session
 
 from danswer.db.models import Tool
 from danswer.server.features.tool.models import Header
+from danswer.utils.headers import HeaderItemDict
 from danswer.utils.logger import setup_logger
 
 logger = setup_logger()
@@ -67,7 +69,9 @@ def update_tool(
     if user_id is not None:
         tool.user_id = user_id
     if custom_headers is not None:
-        tool.custom_headers = [header.dict() for header in custom_headers]
+        tool.custom_headers = [
+            cast(HeaderItemDict, header.model_dump()) for header in custom_headers
+        ]
     db_session.commit()
 
     return tool

backend/danswer/llm/factory.py

@@ -7,9 +7,9 @@ from danswer.db.llm import fetch_provider
 from danswer.db.models import Persona
 from danswer.llm.chat_llm import DefaultMultiLLM
 from danswer.llm.exceptions import GenAIDisabledException
-from danswer.llm.headers import build_llm_extra_headers
 from danswer.llm.interfaces import LLM
 from danswer.llm.override_models import LLMOverride
+from danswer.utils.headers import build_llm_extra_headers
 
 
 def get_main_llm_from_tuple(

backend/danswer/llm/headers.py

@@ -1,12 +0,0 @@
-from danswer.configs.model_configs import LITELLM_EXTRA_HEADERS
-
-
-def build_llm_extra_headers(
-    additional_headers: dict[str, str] | None = None
-) -> dict[str, str]:
-    extra_headers: dict[str, str] = {}
-    if additional_headers:
-        extra_headers.update(additional_headers)
-    if LITELLM_EXTRA_HEADERS:
-        extra_headers.update(LITELLM_EXTRA_HEADERS)
-    return extra_headers

backend/danswer/server/query_and_chat/chat_backend.py

@@ -25,7 +25,6 @@ from danswer.configs.app_configs import WEB_DOMAIN
 from danswer.configs.constants import FileOrigin
 from danswer.configs.constants import MessageType
 from danswer.configs.model_configs import LITELLM_PASS_THROUGH_HEADERS
-from danswer.configs.model_configs import TOOL_PASS_THROUGH_HEADERS
 from danswer.db.chat import create_chat_session
 from danswer.db.chat import create_new_chat_message
 from danswer.db.chat import delete_chat_session
@@ -74,6 +73,7 @@ from danswer.server.query_and_chat.models import RenameChatSessionResponse
 from danswer.server.query_and_chat.models import SearchFeedbackRequest
 from danswer.server.query_and_chat.models import UpdateChatSessionThreadRequest
 from danswer.server.query_and_chat.token_limit import check_token_rate_limits
+from danswer.utils.headers import get_custom_tool_additional_request_headers
 from danswer.utils.logger import setup_logger
 
 
@@ -338,8 +338,8 @@ def handle_new_chat_message(
                 litellm_additional_headers=extract_headers(
                     request.headers, LITELLM_PASS_THROUGH_HEADERS
                 ),
-                tool_additional_headers=extract_headers(
-                    request.headers, TOOL_PASS_THROUGH_HEADERS
+                custom_tool_additional_headers=get_custom_tool_additional_request_headers(
+                    request.headers
                 ),
                 is_connected=is_disconnected_func,
             ):

backend/danswer/tools/custom/custom_tool.py

@@ -29,6 +29,8 @@ from danswer.tools.models import DynamicSchemaInfo
 from danswer.tools.models import MESSAGE_ID_PLACEHOLDER
 from danswer.tools.tool import Tool
 from danswer.tools.tool import ToolResponse
+from danswer.utils.headers import header_list_to_header_dict
+from danswer.utils.headers import HeaderItemDict
 from danswer.utils.logger import setup_logger
 
 logger = setup_logger()
@@ -46,8 +48,7 @@ class CustomTool(Tool):
         self,
         method_spec: MethodSpec,
         base_url: str,
-        custom_headers: list[dict[str, str]] | None = [],
-        tool_additional_headers: dict[str, str] | None = None,
+        custom_headers: list[HeaderItemDict] | None = None,
     ) -> None:
         self._base_url = base_url
         self._method_spec = method_spec
@@ -55,9 +56,9 @@ class CustomTool(Tool):
 
         self._name = self._method_spec.name
         self._description = self._method_spec.summary
-        self.headers = {
-            header["key"]: header["value"] for header in (custom_headers or [])
-        } | (tool_additional_headers or {})
+        self.headers = (
+            header_list_to_header_dict(custom_headers) if custom_headers else {}
+        )
 
     @property
     def name(self) -> str:
@@ -184,8 +185,7 @@ class CustomTool(Tool):
 
 def build_custom_tools_from_openapi_schema_and_headers(
     openapi_schema: dict[str, Any],
-    tool_additional_headers: dict[str, str] | None = None,
-    custom_headers: list[dict[str, str]] | None = [],
+    custom_headers: list[HeaderItemDict] | None = None,
     dynamic_schema_info: DynamicSchemaInfo | None = None,
 ) -> list[CustomTool]:
     if dynamic_schema_info:
@@ -205,8 +205,7 @@ def build_custom_tools_from_openapi_schema_and_headers(
     url = openapi_to_url(openapi_schema)
     method_specs = openapi_to_method_specs(openapi_schema)
     return [
-        CustomTool(method_spec, url, custom_headers, tool_additional_headers)
-        for method_spec in method_specs
+        CustomTool(method_spec, url, custom_headers) for method_spec in method_specs
     ]
 
 

backend/danswer/tools/images/image_generation_tool.py

@@ -11,13 +11,13 @@ from danswer.chat.chat_utils import combine_message_chain
 from danswer.configs.model_configs import GEN_AI_HISTORY_CUTOFF
 from danswer.key_value_store.interface import JSON_ro
 from danswer.llm.answering.models import PreviousMessage
-from danswer.llm.headers import build_llm_extra_headers
 from danswer.llm.interfaces import LLM
 from danswer.llm.utils import build_content_with_imgs
 from danswer.llm.utils import message_to_string
 from danswer.prompts.constants import GENERAL_SEP_PAT
 from danswer.tools.tool import Tool
 from danswer.tools.tool import ToolResponse
+from danswer.utils.headers import build_llm_extra_headers
 from danswer.utils.logger import setup_logger
 from danswer.utils.threadpool_concurrency import run_functions_tuples_in_parallel
 

backend/danswer/utils/headers.py

@@ -0,0 +1,79 @@
+from typing import TypedDict
+
+from fastapi.datastructures import Headers
+
+from danswer.configs.model_configs import LITELLM_EXTRA_HEADERS
+from danswer.configs.model_configs import LITELLM_PASS_THROUGH_HEADERS
+from danswer.configs.tool_configs import CUSTOM_TOOL_PASS_THROUGH_HEADERS
+from danswer.utils.logger import setup_logger
+
+logger = setup_logger()
+
+
+class HeaderItemDict(TypedDict):
+    key: str
+    value: str
+
+
+def clean_header_list(headers_to_clean: list[HeaderItemDict]) -> dict[str, str]:
+    cleaned_headers: dict[str, str] = {}
+    for item in headers_to_clean:
+        key = item["key"]
+        value = item["value"]
+        if key in cleaned_headers:
+            logger.warning(
+                f"Duplicate header {key} found in custom headers, ignoring..."
+            )
+            continue
+        cleaned_headers[key] = value
+    return cleaned_headers
+
+
+def header_dict_to_header_list(header_dict: dict[str, str]) -> list[HeaderItemDict]:
+    return [{"key": key, "value": value} for key, value in header_dict.items()]
+
+
+def header_list_to_header_dict(header_list: list[HeaderItemDict]) -> dict[str, str]:
+    return {header["key"]: header["value"] for header in header_list}
+
+
+def get_relevant_headers(
+    headers: dict[str, str] | Headers, desired_headers: list[str] | None
+) -> dict[str, str]:
+    if not desired_headers:
+        return {}
+
+    pass_through_headers: dict[str, str] = {}
+    for key in desired_headers:
+        if key in headers:
+            pass_through_headers[key] = headers[key]
+        else:
+            # fastapi makes all header keys lowercase, handling that here
+            lowercase_key = key.lower()
+            if lowercase_key in headers:
+                pass_through_headers[lowercase_key] = headers[lowercase_key]
+
+    return pass_through_headers
+
+
+def get_litellm_additional_request_headers(
+    headers: dict[str, str] | Headers
+) -> dict[str, str]:
+    return get_relevant_headers(headers, LITELLM_PASS_THROUGH_HEADERS)
+
+
+def build_llm_extra_headers(
+    additional_headers: dict[str, str] | None = None
+) -> dict[str, str]:
+    extra_headers: dict[str, str] = {}
+    if additional_headers:
+        extra_headers.update(additional_headers)
+    if LITELLM_EXTRA_HEADERS:
+        extra_headers.update(LITELLM_EXTRA_HEADERS)
+    return extra_headers
+
+
+def get_custom_tool_additional_request_headers(
+    headers: dict[str, str] | Headers
+) -> dict[str, str]:
+    return get_relevant_headers(headers, CUSTOM_TOOL_PASS_THROUGH_HEADERS)

backend/tests/unit/danswer/tools/custom/test_custom_tools.py

@@ -13,6 +13,7 @@ from danswer.tools.custom.custom_tool import CustomToolCallSummary
 from danswer.tools.custom.custom_tool import validate_openapi_schema
 from danswer.tools.models import DynamicSchemaInfo
 from danswer.tools.tool import ToolResponse
+from danswer.utils.headers import HeaderItemDict
 
 
 class TestCustomTool(unittest.TestCase):
@@ -143,7 +144,7 @@ class TestCustomTool(unittest.TestCase):
         Test the custom tool with custom headers.
         Verifies that the tool correctly includes the custom headers in the request.
         """
-        custom_headers: list[dict[str, str]] = [
+        custom_headers: list[HeaderItemDict] = [
             {"key": "Authorization", "value": "Bearer token123"},
             {"key": "Custom-Header", "value": "CustomValue"},
         ]
@@ -171,7 +172,7 @@ class TestCustomTool(unittest.TestCase):
         Test the custom tool with an empty list of custom headers.
         Verifies that the tool correctly handles an empty list of headers.
         """
-        custom_headers: list[dict[str, str]] = []
+        custom_headers: list[HeaderItemDict] = []
         tools = build_custom_tools_from_openapi_schema_and_headers(
             self.openapi_schema,
             custom_headers=custom_headers,