rework output type socket to be more flexible

backend/node_registry.py

@@ -15,6 +15,30 @@ NODE_CLASS_MAPPINGS: dict[str, type] = {}
 NODE_DISPLAY_NAME_MAPPINGS: dict[str, str] = {}
 
 
+def get_node_output_specs(cls: type) -> tuple[tuple[str, str], ...]:
+    raw_outputs = getattr(cls, "OUTPUTS", None)
+    if raw_outputs is None:
+        raise AttributeError(f"{cls.__name__} must define OUTPUTS.")
+
+    specs: list[tuple[str, str]] = []
+    for index, output in enumerate(raw_outputs):
+        if not isinstance(output, (list, tuple)) or len(output) != 2:
+            raise TypeError(
+                f"{cls.__name__}.OUTPUTS[{index}] must be a 2-item tuple of (type, name)."
+            )
+        type_name, name = output
+        specs.append((str(type_name), str(name)))
+    return tuple(specs)
+
+
+def get_node_output_types(cls: type) -> tuple[str, ...]:
+    return tuple(type_name for type_name, _ in get_node_output_specs(cls))
+
+
+def get_node_output_names(cls: type) -> tuple[str, ...]:
+    return tuple(name for _, name in get_node_output_specs(cls))
+
+
 def register_node(display_name: str | None = None):
     """
     Class decorator that registers a node class into NODE_CLASS_MAPPINGS.
@@ -25,6 +49,7 @@ def register_node(display_name: str | None = None):
             ...
     """
     def decorator(cls: type) -> type:
+        get_node_output_specs(cls)
         name = cls.__name__
         NODE_CLASS_MAPPINGS[name] = cls
         NODE_DISPLAY_NAME_MAPPINGS[name] = display_name or name
@@ -50,8 +75,8 @@ def get_node_info(class_name: str) -> dict[str, Any]:
         "menu_categories": list(menu_metadata.get("menu_categories", [])),
         "input": input_types,
         "input_order": {k: list(v.keys()) for k, v in input_types.items()},
-        "output": list(cls.RETURN_TYPES),
-        "output_name": list(getattr(cls, "RETURN_NAMES", cls.RETURN_TYPES)),
+        "output": list(get_node_output_types(cls)),
+        "output_name": list(get_node_output_names(cls)),
         "output_node": bool(getattr(cls, "OUTPUT_NODE", False)),
         "manual_trigger": bool(getattr(cls, "MANUAL_TRIGGER", False)),
         "description": getattr(cls, "DESCRIPTION", ""),