feat: Add ruff rules for error messages (EM) (langflow-ai#3978)

Add ruff rules for error messages (EM)

src/backend/base/langflow/__main__.py

@@ -403,7 +403,8 @@ def superuser(
             if result:
                 typer.echo("Default folder created successfully.")
             else:
-                raise RuntimeError("Could not create default folder.")
+                msg = "Could not create default folder."
+                raise RuntimeError(msg)
             typer.echo("Superuser created successfully.")
 
         else:

src/backend/base/langflow/api/utils.py

@@ -135,7 +135,8 @@ async def build_graph_from_data(flow_id: str, payload: dict, **kwargs):
     for vertex_id in graph._has_session_id_vertices:
         vertex = graph.get_vertex(vertex_id)
         if vertex is None:
-            raise ValueError(f"Vertex {vertex_id} not found")
+            msg = f"Vertex {vertex_id} not found"
+            raise ValueError(msg)
         if not vertex._raw_params.get("session_id"):
             vertex.update_raw_params({"session_id": flow_id}, overwrite=True)
 
@@ -150,7 +151,8 @@ async def build_graph_from_db_no_cache(flow_id: str, session: Session):
     """Build and cache the graph."""
     flow: Flow | None = session.get(Flow, flow_id)
     if not flow or not flow.data:
-        raise ValueError("Invalid flow ID")
+        msg = "Invalid flow ID"
+        raise ValueError(msg)
     return await build_graph_from_data(flow_id, flow.data, flow_name=flow.name, user_id=str(flow.user_id))
 
 
@@ -260,4 +262,5 @@ async def cascade_delete_flow(session: Session, flow: Flow):
         session.exec(delete(VertexBuildTable).where(VertexBuildTable.flow_id == flow.id))  # type: ignore
         session.exec(delete(Flow).where(Flow.id == flow.id))  # type: ignore
     except Exception as e:
-        raise RuntimeError(f"Unable to cascade delete flow: ${flow.id}", e)
+        msg = f"Unable to cascade delete flow: ${flow.id}"
+        raise RuntimeError(msg, e)

src/backend/base/langflow/api/v1/chat.py

@@ -340,7 +340,8 @@ async def build_vertices(
             vertex_build_response_json = vertex_build_response.model_dump_json()
             build_data = json.loads(vertex_build_response_json)
         except Exception as exc:
-            raise ValueError(f"Error serializing vertex build response: {exc}") from exc
+            msg = f"Error serializing vertex build response: {exc}"
+            raise ValueError(msg) from exc
         event_manager.on_end_vertex(data={"build_data": build_data})
         await client_consumed_queue.get()
         if vertex_build_response.valid:
@@ -652,13 +653,15 @@ async def stream_vertex():
                 cache = await chat_service.get_cache(flow_id_str)
                 if not cache:
                     # If there's no cache
-                    raise ValueError(f"No cache found for {flow_id_str}.")
+                    msg = f"No cache found for {flow_id_str}."
+                    raise ValueError(msg)
                 else:
                     graph = cache.get("result")
 
                 vertex: InterfaceVertex = graph.get_vertex(vertex_id)
                 if not hasattr(vertex, "stream"):
-                    raise ValueError(f"Vertex {vertex_id} does not support streaming")
+                    msg = f"Vertex {vertex_id} does not support streaming"
+                    raise ValueError(msg)
                 if isinstance(vertex._built_result, str) and vertex._built_result:
                     stream_data = StreamData(
                         event="message",
@@ -691,7 +694,8 @@ async def stream_vertex():
                     )
                     yield str(stream_data)
                 else:
-                    raise ValueError(f"No result found for vertex {vertex_id}")
+                    msg = f"No result found for vertex {vertex_id}"
+                    raise ValueError(msg)
 
             except Exception as exc:
                 logger.exception(f"Error building Component: {exc}")

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

@@ -94,17 +94,15 @@ def validate_input_and_tweaks(input_request: SimplifiedAPIRequest):
                 has_input_value = value.get("input_value") is not None
                 input_value_is_chat = input_request.input_value is not None and input_request.input_type == "chat"
                 if has_input_value and input_value_is_chat:
-                    raise InvalidChatInputException(
-                        "If you pass an input_value to the chat input, you cannot pass a tweak with the same name."
-                    )
+                    msg = "If you pass an input_value to the chat input, you cannot pass a tweak with the same name."
+                    raise InvalidChatInputException(msg)
         elif "Text Input" in key or "TextInput" in key:
             if isinstance(value, dict):
                 has_input_value = value.get("input_value") is not None
                 input_value_is_text = input_request.input_value is not None and input_request.input_type == "text"
                 if has_input_value and input_value_is_text:
-                    raise InvalidChatInputException(
-                        "If you pass an input_value to the text input, you cannot pass a tweak with the same name."
-                    )
+                    msg = "If you pass an input_value to the text input, you cannot pass a tweak with the same name."
+                    raise InvalidChatInputException(msg)
 
 
 async def simple_run_flow(
@@ -120,7 +118,8 @@ async def simple_run_flow(
         user_id = api_key_user.id if api_key_user else None
         flow_id_str = str(flow.id)
         if flow.data is None:
-            raise ValueError(f"Flow {flow_id_str} has no data")
+            msg = f"Flow {flow_id_str} has no data"
+            raise ValueError(msg)
         graph_data = flow.data.copy()
         graph_data = process_tweaks(graph_data, input_request.tweaks or {}, stream=stream)
         graph = Graph.from_payload(graph_data, flow_id=flow_id_str, user_id=str(user_id), flow_name=flow.name)
@@ -331,8 +330,9 @@ async def webhook_run_flow(
         data = await request.body()
         if not data:
             logger.error("Request body is empty")
+            msg = "Request body is empty. You should provide a JSON payload containing the flow ID."
             raise ValueError(
-                "Request body is empty. You should provide a JSON payload containing the flow ID.",
+                msg,
             )
 
         # get all webhook components in the flow
@@ -448,18 +448,21 @@ async def experimental_run_flow(
             session_data = await session_service.load_session(session_id, flow_id=flow_id_str)
             graph, artifacts = session_data if session_data else (None, None)
             if graph is None:
-                raise ValueError(f"Session {session_id} not found")
+                msg = f"Session {session_id} not found"
+                raise ValueError(msg)
         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_str).where(Flow.user_id == api_key_user.id)
             ).first()
             if flow is None:
-                raise ValueError(f"Flow {flow_id_str} not found")
+                msg = f"Flow {flow_id_str} not found"
+                raise ValueError(msg)
 
             if flow.data is None:
-                raise ValueError(f"Flow {flow_id_str} has no data")
+                msg = f"Flow {flow_id_str} has no data"
+                raise ValueError(msg)
             graph_data = flow.data
             graph_data = process_tweaks(graph_data, tweaks or {})
             graph = Graph.from_payload(graph_data, flow_id=flow_id_str)

src/backend/base/langflow/api/v1/schemas.py

@@ -110,7 +110,8 @@ class ChatResponse(ChatMessage):
     @classmethod
     def validate_message_type(cls, v):
         if v not in ["start", "stream", "end", "error", "info", "file"]:
-            raise ValueError("type must be start, stream, end, error, info, or file")
+            msg = "type must be start, stream, end, error, info, or file"
+            raise ValueError(msg)
         return v
 
 
@@ -134,7 +135,8 @@ class FileResponse(ChatMessage):
     @classmethod
     def validate_data_type(cls, v):
         if v not in ["image", "csv"]:
-            raise ValueError("data_type must be image or csv")
+            msg = "data_type must be image or csv"
+            raise ValueError(msg)
         return v
 
 

src/backend/base/langflow/base/agents/agent.py

@@ -67,9 +67,11 @@ def _validate_outputs(self):
         output_names = [output.name for output in self.outputs]
         for method_name in required_output_methods:
             if method_name not in output_names:
-                raise ValueError(f"Output with name '{method_name}' must be defined.")
+                msg = f"Output with name '{method_name}' must be defined."
+                raise ValueError(msg)
             elif not hasattr(self, method_name):
-                raise ValueError(f"Method '{method_name}' must be defined.")
+                msg = f"Method '{method_name}' must be defined."
+                raise ValueError(msg)
 
     def get_agent_kwargs(self, flatten: bool = False) -> dict:
         base = {
@@ -102,7 +104,8 @@ async def run_agent(self, agent: AgentExecutor) -> Text:
         )
         self.status = result
         if "output" not in result:
-            raise ValueError("Output key not found in result. Tried 'output'.")
+            msg = "Output key not found in result. Tried 'output'."
+            raise ValueError(msg)
 
         return cast(str, result.get("output"))
 
@@ -148,7 +151,8 @@ async def run_agent(
         )
         self.status = result
         if "output" not in result:
-            raise ValueError("Output key not found in result. Tried 'output'.")
+            msg = "Output key not found in result. Tried 'output'."
+            raise ValueError(msg)
 
         return cast(str, result.get("output"))
 

src/backend/base/langflow/base/agents/crewai/crew.py

@@ -46,7 +46,8 @@ def get_tasks_and_agents(self) -> tuple[list[Task], list[Agent]]:
         return self.tasks, self.agents
 
     def build_crew(self) -> Crew:
-        raise NotImplementedError("build_crew must be implemented in subclasses")
+        msg = "build_crew must be implemented in subclasses"
+        raise NotImplementedError(msg)
 
     def get_task_callback(
         self,

src/backend/base/langflow/base/chains/model.py

@@ -12,6 +12,8 @@ def _validate_outputs(self):
         output_names = [output.name for output in self.outputs]
         for method_name in required_output_methods:
             if method_name not in output_names:
-                raise ValueError(f"Output with name '{method_name}' must be defined.")
+                msg = f"Output with name '{method_name}' must be defined."
+                raise ValueError(msg)
             elif not hasattr(self, method_name):
-                raise ValueError(f"Method '{method_name}' must be defined.")
+                msg = f"Method '{method_name}' must be defined."
+                raise ValueError(msg)

src/backend/base/langflow/base/curl/parse.py

@@ -49,7 +49,8 @@ def parse_curl_command(curl_command):
     tokens = shlex.split(normalize_newlines(curl_command))
     tokens = [token for token in tokens if token and token != " "]
     if tokens and "curl" not in tokens[0]:
-        raise ValueError("Invalid curl command")
+        msg = "Invalid curl command"
+        raise ValueError(msg)
     args_template = {
         "command": None,
         "url": None,

src/backend/base/langflow/base/data/utils.py

@@ -53,7 +53,8 @@ def retrieve_file_paths(
 ) -> list[str]:
     path_obj = Path(path)
     if not path_obj.exists() or not path_obj.is_dir():
-        raise ValueError(f"Path {path} must exist and be a directory.")
+        msg = f"Path {path} must exist and be a directory."
+        raise ValueError(msg)
 
     def match_types(p: Path) -> bool:
         return any(p.suffix == f".{t}" for t in types) if types else True
@@ -83,7 +84,8 @@ def partition_file_to_data(file_path: str, silent_errors: bool) -> Data | None:
         elements = partition(file_path)
     except Exception as e:
         if not silent_errors:
-            raise ValueError(f"Error loading file {file_path}: {e}") from e
+            msg = f"Error loading file {file_path}: {e}"
+            raise ValueError(msg) from e
         return None
 
     # Create a Data
@@ -147,7 +149,8 @@ def parse_text_file_to_data(file_path: str, silent_errors: bool) -> Data | None:
             text = ET.tostring(xml_element, encoding="unicode")
     except Exception as e:
         if not silent_errors:
-            raise ValueError(f"Error loading file {file_path}: {e}") from e
+            msg = f"Error loading file {file_path}: {e}"
+            raise ValueError(msg) from e
         return None
 
     record = Data(data={"file_path": file_path, "text": text})

src/backend/base/langflow/base/embeddings/model.py

@@ -15,9 +15,12 @@ def _validate_outputs(self):
         output_names = [output.name for output in self.outputs]
         for method_name in required_output_methods:
             if method_name not in output_names:
-                raise ValueError(f"Output with name '{method_name}' must be defined.")
+                msg = f"Output with name '{method_name}' must be defined."
+                raise ValueError(msg)
             elif not hasattr(self, method_name):
-                raise ValueError(f"Method '{method_name}' must be defined.")
+                msg = f"Method '{method_name}' must be defined."
+                raise ValueError(msg)
 
     def build_embeddings(self) -> Embeddings:
-        raise NotImplementedError("You must implement the build_embeddings method in your class.")
+        msg = "You must implement the build_embeddings method in your class."
+        raise NotImplementedError(msg)

src/backend/base/langflow/base/io/chat.py

@@ -22,7 +22,8 @@ def store_message(
             flow_id=self.graph.flow_id,
         )
         if len(messages) > 1:
-            raise ValueError("Only one message can be stored at a time.")
+            msg = "Only one message can be stored at a time."
+            raise ValueError(msg)
         stored_message = messages[0]
         if hasattr(self, "_event_manager") and self._event_manager and stored_message.id:
             if not isinstance(message.text, str):
@@ -55,7 +56,8 @@ async def _handle_async_iterator(self, iterator: AsyncIterator, message: Message
     def _stream_message(self, message: Message, message_id: str) -> str:
         iterator = message.text
         if not isinstance(iterator, AsyncIterator | Iterator):
-            raise ValueError("The message must be an iterator or an async iterator.")
+            msg = "The message must be an iterator or an async iterator."
+            raise ValueError(msg)
 
         if isinstance(iterator, AsyncIterator):
             return run_until_complete(self._handle_async_iterator(iterator, message, message_id))

src/backend/base/langflow/base/langchain_utilities/model.py

@@ -19,9 +19,11 @@ def _validate_outputs(self):
         output_names = [output.name for output in self.outputs]
         for method_name in required_output_methods:
             if method_name not in output_names:
-                raise ValueError(f"Output with name '{method_name}' must be defined.")
+                msg = f"Output with name '{method_name}' must be defined."
+                raise ValueError(msg)
             elif not hasattr(self, method_name):
-                raise ValueError(f"Method '{method_name}' must be defined.")
+                msg = f"Method '{method_name}' must be defined."
+                raise ValueError(msg)
 
     @abstractmethod
     def run_model(self) -> Data | list[Data]:

src/backend/base/langflow/base/memory/model.py

@@ -22,9 +22,11 @@ def _validate_outputs(self):
         output_names = [output.name for output in self.outputs]
         for method_name in required_output_methods:
             if method_name not in output_names:
-                raise ValueError(f"Output with name '{method_name}' must be defined.")
+                msg = f"Output with name '{method_name}' must be defined."
+                raise ValueError(msg)
             elif not hasattr(self, method_name):
-                raise ValueError(f"Method '{method_name}' must be defined.")
+                msg = f"Method '{method_name}' must be defined."
+                raise ValueError(msg)
 
     def build_base_memory(self) -> BaseChatMemory:
         return ConversationBufferMemory(chat_memory=self.build_message_history())

src/backend/base/langflow/base/models/model.py

@@ -48,9 +48,11 @@ def _validate_outputs(self):
         output_names = [output.name for output in self.outputs]
         for method_name in required_output_methods:
             if method_name not in output_names:
-                raise ValueError(f"Output with name '{method_name}' must be defined.")
+                msg = f"Output with name '{method_name}' must be defined."
+                raise ValueError(msg)
             elif not hasattr(self, method_name):
-                raise ValueError(f"Method '{method_name}' must be defined.")
+                msg = f"Method '{method_name}' must be defined."
+                raise ValueError(msg)
 
     def text_response(self) -> Message:
         input_value = self.input_value
@@ -145,7 +147,8 @@ def get_chat_result(
     ):
         messages: list[BaseMessage] = []
         if not input_value and not system_message:
-            raise ValueError("The message you want to send to the model is empty.")
+            msg = "The message you want to send to the model is empty."
+            raise ValueError(msg)
         system_message_added = False
         if input_value:
             if isinstance(input_value, Message):

src/backend/base/langflow/base/prompts/api_utils.py

@@ -127,14 +127,16 @@ def validate_prompt(prompt_template: str, silent_errors: bool = False) -> list[s
     # Check if there are invalid characters in the input_variables
     input_variables = _check_input_variables(input_variables)
     if any(var in _INVALID_NAMES for var in input_variables):
-        raise ValueError(f"Invalid input variables. None of the variables can be named {', '.join(input_variables)}. ")
+        msg = f"Invalid input variables. None of the variables can be named {', '.join(input_variables)}. "
+        raise ValueError(msg)
 
     try:
         PromptTemplate(template=prompt_template, input_variables=input_variables)
     except Exception as exc:
         logger.error(f"Invalid prompt: {exc}")
         if not silent_errors:
-            raise ValueError(f"Invalid prompt: {exc}") from exc
+            msg = f"Invalid prompt: {exc}"
+            raise ValueError(msg) from exc
 
     return input_variables
 

src/backend/base/langflow/base/textsplitters/model.py

@@ -14,9 +14,11 @@ def _validate_outputs(self):
         output_names = [output.name for output in self.outputs]
         for method_name in required_output_methods:
             if method_name not in output_names:
-                raise ValueError(f"Output with name '{method_name}' must be defined.")
+                msg = f"Output with name '{method_name}' must be defined."
+                raise ValueError(msg)
             elif not hasattr(self, method_name):
-                raise ValueError(f"Method '{method_name}' must be defined.")
+                msg = f"Method '{method_name}' must be defined."
+                raise ValueError(msg)
 
     def build_document_transformer(self) -> BaseDocumentTransformer:
         return self.build_text_splitter()

src/backend/base/langflow/base/tools/component_tool.py

@@ -35,7 +35,8 @@ def _run(
             results, _ = self.component(**kwargs)
             return results
         except Exception as e:
-            raise ToolException(f"Error running {self.name}: {e}")
+            msg = f"Error running {self.name}: {e}"
+            raise ToolException(msg)
 
 
 ComponentTool.update_forward_refs()