comfyui-node-advanced

ComfyUI Advanced Node Patterns (V3)

V3 provides advanced input patterns for dynamic, type-safe, and flexible node designs.

MatchType - Generic Type Connections

MatchType ensures that inputs and outputs sharing a template have the same type at connection time. Like generics in typed languages.

class PassThrough(io.ComfyNode):
    @classmethod
    def define_schema(cls):
        # Template(template_id, allowed_types=AnyType) - optional type constraint
        template = io.MatchType.Template("T")
        return io.Schema(
            node_id="PassThrough",
            display_name="Pass Through",
            category="utils",
            inputs=[
                io.MatchType.Input("value", template=template),
            ],
            outputs=[
                io.MatchType.Output(template=template, display_name="output"),
            ],
        )

    @classmethod
    def execute(cls, value):
        return io.NodeOutput(value)

When the user connects an IMAGE to the input, the output automatically becomes IMAGE type.

Switch Node Pattern

Core Switch (since v0.35) makes both branches optional so either may be left disconnected. A disconnected optional input is absent from kwargs; a connected-but-unevaluated lazy input is None. Use a sentinel to tell them apart:

MISSING = object()

class Switch(io.ComfyNode):
    @classmethod
    def define_schema(cls):
        template = io.MatchType.Template("switch")
        return io.Schema(
            node_id="Switch",
            display_name="Switch",
            category="logic",
            inputs=[
                io.Boolean.Input("switch"),
                io.MatchType.Input("on_false", template=template, lazy=True, optional=True),
                io.MatchType.Input("on_true", template=template, lazy=True, optional=True),
            ],
            outputs=[
                io.MatchType.Output(template=template, display_name="output"),
            ],
        )

    @classmethod
    def check_lazy_status(cls, switch, on_false=MISSING, on_true=MISSING):
        if switch and on_true is None:      # connected, not yet evaluated
            return ["on_true"]
        if not switch and on_false is None:
            return ["on_false"]

    @classmethod
    def execute(cls, switch, on_true=MISSING, on_false=MISSING):
        selected = on_true if switch else on_false
        return io.NodeOutput(None if selected is MISSING else selected)