Command errors?

[garethsb]

If a client sends a WebSocket command which is not even syntactically valid JSON, is there any means for the server to indicate this:

• i.e. send an error message back,
• or close the WebSocket connection from the server side,
• or can it only just ignore the command?

How about if the command message is valid JSON, and also validates against one of the command schemas (or better, the top-level one proposed in #35 (comment)), but is semantically invalid - e.g. one of the specified "sources" in a subscription command doesn't exist?

I am imagining it might be worth defining an error message type in Message types, with a payload of the NMOS core error type? (I see no harm in reusing HTTP status codes here.)

Some clarification of command error handling would be good in v1.0.x documentation, but adding an error response has to wait for v1.1, I guess!

[mjeras]

It is a v1.1 issue, to be discussed later

[garethsb]

We also noted on the call that it would ideally involve a way for an error response to identify which command message it is referring to, which is non-trivial.