Add is_input and is_output attributes to CustomComponent and FrontendNode classes

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

@@ -37,4 +37,6 @@ ATTR_FUNC_MAPPING = {
     "documentation": getattr_return_str,
     "icon": validate_icon,
     "pinned": getattr_return_bool,
+    "is_input": getattr_return_bool,
+    "is_output": getattr_return_bool,
 }

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

@@ -35,6 +35,7 @@ from langflow.utils import validate
 
 if TYPE_CHECKING:
     from langflow.graph.edge.base import ContractEdge
+    from langflow.graph.vertex.base import Vertex
 
 
 class CustomComponent(Component):
@@ -44,6 +45,12 @@ class CustomComponent(Component):
     """The description of the component. Defaults to None."""
     icon: Optional[str] = None
     """The icon of the component. It should be an emoji. Defaults to None."""
+    is_input: Optional[bool] = None
+    """The input state of the component. Defaults to None.
+    If True, the component must have a field named 'message'."""
+    is_output: Optional[bool] = None
+    """The output state of the component. Defaults to None.
+    If True, the component must have a field named 'message'."""
     code: Optional[str] = None
     """The code of the component. Defaults to None."""
     field_config: dict = {}
@@ -56,7 +63,7 @@ class CustomComponent(Component):
     """The build parameters of the component. Defaults to None."""
     selected_output_type: Optional[str] = None
     """The selected output type of the component. Defaults to None."""
-    outgoing_edges: Optional[List["ContractEdge"]] = None
+    vertex: Optional["Vertex"] = None
     """The edge target parameter of the component. Defaults to None."""
     code_class_base_inheritance: ClassVar[str] = "CustomComponent"
     function_entrypoint_name: ClassVar[str] = "build"
@@ -65,6 +72,7 @@ class CustomComponent(Component):
     user_id: Optional[Union[UUID, str]] = None
     status: Optional[Any] = None
     """The status of the component. This is displayed on the frontend. Defaults to None."""
+
     _tree: Optional[dict] = None
 
     def __init__(self, **data):

src/backend/langflow/template/frontend_node/base.py

@@ -47,6 +47,12 @@ class FrontendNode(BaseModel):
     """Description of the frontend node."""
     icon: Optional[str] = None
     """Icon of the frontend node."""
+    is_input: Optional[bool] = None
+    """Whether the frontend node is used as an input when processing the Graph.
+    If True, there should be a field named 'message'."""
+    is_output: Optional[bool] = None
+    """Whether the frontend node is used as an output when processing the Graph.
+    If True, there should be a field named 'message'."""
     is_composition: Optional[bool] = None
     """Whether the frontend node is used for composition."""
     base_classes: List[str]
@@ -165,7 +171,9 @@ class FrontendNode(BaseModel):
         return _type
 
     @staticmethod
-    def handle_special_field(field, key: str, _type: str, SPECIAL_FIELD_HANDLERS) -> str:
+    def handle_special_field(
+        field, key: str, _type: str, SPECIAL_FIELD_HANDLERS
+    ) -> str:
         """Handles special field by using the respective handler if present."""
         handler = SPECIAL_FIELD_HANDLERS.get(key)
         return handler(field) if handler else _type
@@ -176,7 +184,11 @@ class FrontendNode(BaseModel):
         if "dict" in _type.lower() and field.name == "dict_":
             field.field_type = "file"
             field.file_types = [".json", ".yaml", ".yml"]
-        elif _type.startswith("Dict") or _type.startswith("Mapping") or _type.startswith("dict"):
+        elif (
+            _type.startswith("Dict")
+            or _type.startswith("Mapping")
+            or _type.startswith("dict")
+        ):
             field.field_type = "dict"
         return _type
 
@@ -187,7 +199,9 @@ class FrontendNode(BaseModel):
             field.value = value["default"]
 
     @staticmethod
-    def handle_specific_field_values(field: TemplateField, key: str, name: Optional[str] = None) -> None:
+    def handle_specific_field_values(
+        field: TemplateField, key: str, name: Optional[str] = None
+    ) -> None:
         """Handles specific field values for certain fields."""
         if key == "headers":
             field.value = """{"Authorization": "Bearer <token>"}"""
@@ -195,7 +209,9 @@ class FrontendNode(BaseModel):
         FrontendNode._handle_api_key_specific_field_values(field, key, name)
 
     @staticmethod
-    def _handle_model_specific_field_values(field: TemplateField, key: str, name: Optional[str] = None) -> None:
+    def _handle_model_specific_field_values(
+        field: TemplateField, key: str, name: Optional[str] = None
+    ) -> None:
         """Handles specific field values related to models."""
         model_dict = {
             "OpenAI": constants.OPENAI_MODELS,
@@ -208,7 +224,9 @@ class FrontendNode(BaseModel):
             field.is_list = True
 
     @staticmethod
-    def _handle_api_key_specific_field_values(field: TemplateField, key: str, name: Optional[str] = None) -> None:
+    def _handle_api_key_specific_field_values(
+        field: TemplateField, key: str, name: Optional[str] = None
+    ) -> None:
         """Handles specific field values related to API keys."""
         if "api_key" in key and "OpenAI" in str(name):
             field.display_name = "OpenAI API Key"
@@ -248,7 +266,10 @@ class FrontendNode(BaseModel):
     @staticmethod
     def should_be_password(key: str, show: bool) -> bool:
         """Determines whether the field should be a password field."""
-        return any(text in key.lower() for text in {"password", "token", "api", "key"}) and show
+        return (
+            any(text in key.lower() for text in {"password", "token", "api", "key"})
+            and show
+        )
 
     @staticmethod
     def should_be_multiline(key: str) -> bool:

src/frontend/src/types/api/index.ts

@@ -18,6 +18,8 @@ export type APIClassType = {
   template: APITemplateType;
   display_name: string;
   icon?: string;
+  is_input?: boolean;
+  is_output?: boolean;
   input_types?: Array<string>;
   output_types?: Array<string>;
   custom_fields?: CustomFieldsType;