Question: How does DesktopAgentProxy remove event listener?

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Question

My DesktopAgentProxy is listening for ChannelChangedEvent. This event listener was setup using AddEventListenerRequest and AddEventListenerResponse messages. There doesn't seem to be any way to remove this event listener though. I would have expected there to be RemoveEventListenerRequest and RemoveEventListenerResponse

[kriswest]

Through the API fdc3.addEventListener returns a Listener object (as do addContextListener and addIntentListener). However, in the protocol we've given each listener its own message exchange for unsubscribe - but omitted one for the new event listeners.

I can go add a eventListenerUnsubscribeRequest and eventListenerUnsubscribeResponse - although a small voice is telling me we should perhaps be using a single exchange for all of these as they are all the same (payload is based on the listenerUUID).

@robmoffat @Roaders, any thoughts on that? Have a single message exchange for all instances of Listener.unsubscribe?

[Roaders]

From an implementation point of view it's probably going to be easier to have a separate message for each type of listener. Either that or have one message type but with a string union indicating what type of listener is being removed.

I think that I would prefer being able to tell which type of listener that I am removing rather than just relying on a listener ID and potentially needing an extra lookup to figure out what type it is.

Not too bothered though, either would be fine.

[kriswest]

This should do the job in that case: https://github.com/finos/FDC3/commit/f9fddc159404ca130f5335b9acc46290af92b370

If we want to unify these messages in future, I'm sure we could...