Allow user-defined node properties on subflows?

I was wondering if it's on the roadmap the ability to define custom node properties on subflows?

Ideally I'd like to be able to add a configuration to my subflows so that they behave like the custom nodes.

For instance, I should be able to define a "foo" property when I position a subflow on my flow, that will allow me to set the "foo" flow-context variable in the subflow, so that I can use that variable in my subflow logic.

It should allow to define the value of the custom properties reading it from the flow, msg or global, or any custom string, number etc.

Can you come up with a specific use case that this would address?

For instance I have a "Flux Toggle" subflow that handles the logic needed to toggle some lights state, but to provide it the entity (bulb) I want to turn on/off I need to make it read the msg object with a pre-defined property (payload usually), this means that I have to edit my Flow to alter the payload value when I call the subflow and then restore the previous payload after the subflow returns.

Basically I'd like the subflows to behave like the custom nodes, this could even allow to share in the "palettes" listing custom subflows that could be fully encapsulated.

Yes.

Subflow Instance Properties are a key item on our Roadmap to 1.0

Trello Item - https://trello.com/c/Rs5752Ba - including links to the relevant design notes on the wiki.

Nick

Thanks @knolleary! That's great