Refactor code structure and improve error handling

src/backend/langflow/api/v1/endpoints.py

@@ -45,14 +45,16 @@ def get_all(
 
     logger.debug("Building langchain types dict")
     try:
-        all_types_dict = get_all_types_dict(settings_service)
+        all_types_dict = get_all_types_dict(settings_service.settings.COMPONENTS_PATH)
         return all_types_dict
     except Exception as exc:
         logger.exception(exc)
         raise HTTPException(status_code=500, detail=str(exc)) from exc
 
 
-@router.post("/run/{flow_id}", response_model=RunResponse, response_model_exclude_none=True)
+@router.post(
+    "/run/{flow_id}", response_model=RunResponse, response_model_exclude_none=True
+)
 async def run_flow_with_caching(
     session: Annotated[Session, Depends(get_session)],
     flow_id: str,
@@ -111,7 +113,9 @@ async def run_flow_with_caching(
             outputs = []
 
         if session_id:
-            session_data = await session_service.load_session(session_id, flow_id=flow_id)
+            session_data = await session_service.load_session(
+                session_id, flow_id=flow_id
+            )
             graph, artifacts = session_data if session_data else (None, None)
             task_result: Any = None
             if not graph:
@@ -130,7 +134,11 @@ async def run_flow_with_caching(
         else:
             # Get the flow that matches the flow_id and belongs to the user
             # flow = session.query(Flow).filter(Flow.id == flow_id).filter(Flow.user_id == api_key_user.id).first()
-            flow = session.exec(select(Flow).where(Flow.id == flow_id).where(Flow.user_id == api_key_user.id)).first()
+            flow = session.exec(
+                select(Flow)
+                .where(Flow.id == flow_id)
+                .where(Flow.user_id == api_key_user.id)
+            ).first()
             if flow is None:
                 raise ValueError(f"Flow {flow_id} not found")
 
@@ -154,12 +162,18 @@ async def run_flow_with_caching(
         # StatementError('(builtins.ValueError) badly formed hexadecimal UUID string')
         if "badly formed hexadecimal UUID string" in str(exc):
             # This means the Flow ID is not a valid UUID which means it can't find the flow
-            raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=str(exc)) from exc
+            raise HTTPException(
+                status_code=status.HTTP_404_NOT_FOUND, detail=str(exc)
+            ) from exc
     except ValueError as exc:
         if f"Flow {flow_id} not found" in str(exc):
-            raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=str(exc)) from exc
+            raise HTTPException(
+                status_code=status.HTTP_404_NOT_FOUND, detail=str(exc)
+            ) from exc
         else:
-            raise HTTPException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail=str(exc)) from exc
+            raise HTTPException(
+                status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail=str(exc)
+            ) from exc
 
 
 @router.post(
@@ -188,7 +202,8 @@ async def process(
     """
     # Raise a depreciation warning
     logger.warning(
-        "The /process endpoint is deprecated and will be removed in a future version. " "Please use /run instead."
+        "The /process endpoint is deprecated and will be removed in a future version. "
+        "Please use /run instead."
     )
     raise HTTPException(
         status_code=status.HTTP_400_BAD_REQUEST,
@@ -260,12 +275,16 @@ async def custom_component(
 
     built_frontend_node = build_custom_component_template(component, user_id=user.id)
 
-    built_frontend_node = update_frontend_node_with_template_values(built_frontend_node, raw_code.frontend_node)
+    built_frontend_node = update_frontend_node_with_template_values(
+        built_frontend_node, raw_code.frontend_node
+    )
     return built_frontend_node
 
 
 @router.post("/custom_component/reload", status_code=HTTPStatus.OK)
-async def reload_custom_component(path: str, user: User = Depends(get_current_active_user)):
+async def reload_custom_component(
+    path: str, user: User = Depends(get_current_active_user)
+):
     from langflow.interface.custom.utils import build_custom_component_template
 
     try:

src/backend/langflow/interface/custom/utils.py

@@ -426,17 +426,17 @@ def create_component_template(component):
     return component_template
 
 
-def build_custom_components(settings_service):
+def build_custom_components(components_paths: List[str]):
     """Build custom components from the specified paths."""
-    if not settings_service.settings.COMPONENTS_PATH:
+    if not components_paths:
         return {}
 
     logger.info(
-        f"Building custom components from {settings_service.settings.COMPONENTS_PATH}"
+        f"Building custom components from {components_paths}"
     )
     custom_components_from_file = {}
     processed_paths = set()
-    for path in settings_service.settings.COMPONENTS_PATH:
+    for path in components_paths:
         path_str = str(path)
         if path_str in processed_paths:
             continue

src/backend/langflow/interface/listing.py

@@ -21,7 +21,7 @@ class AllTypesDict(LazyLoadDictBase):
         from langflow.interface.types import get_all_types_dict
 
         settings_service = get_settings_service()
-        return get_all_types_dict(settings_service=settings_service)
+        return get_all_types_dict(settings_service.settings.COMPONENTS_PATH)
 
 
 lazy_load_dict = AllTypesDict()

src/backend/langflow/interface/types.py

@@ -1,4 +1,5 @@
 from cachetools import LRUCache, cached
+
 from langflow.interface.agents.base import agent_creator
 from langflow.interface.chains.base import chain_creator
 from langflow.interface.custom.directory_reader.utils import (
@@ -62,8 +63,12 @@ def build_langchain_types_dict():  # sourcery skip: dict-assign-update-to-union
     return all_types
 
 
-def get_all_types_dict(settings_service):
+def get_all_types_dict(components_paths):
     """Get all types dictionary combining native and custom components."""
     native_components = build_langchain_types_dict()
-    custom_components_from_file = build_custom_components(settings_service)
+    custom_components_from_file = build_custom_components(
-    return merge_nested_dicts_with_renaming(native_components, custom_components_from_file)
+        components_paths=components_paths
+    )
+    return merge_nested_dicts_with_renaming(
+        native_components, custom_components_from_file
+    )