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What STOMP Header to Close a Subscription?

Is there a standard way for a server to indicate to a STOMP (web socket) client that it should close the connection? (i.e. 'kick' them from a room).

From what I can tell, there is:

  • a standard frame for a client to UNSUBSCRIBE
  • no frame for kicking or force "unsubscribing" from a topic, at the server's initiative.

Use cases include: closing a topic when all other members have unsubscribed, closing a topic when its temporary use has ended (e.g. fetching a large document).

Solution

  • The STOMP specification has no way to tell a client it needs to unsubscribe from a destination. In my view, if the server deems it necessary that the client should unsubscribe the server should simply disconnect the subscriber and perform the necessary server-side clean-up. STOMP supports certain "server" frames (i.e. MESSAGE, RECEIPT, & ERROR). An ERROR frame might be suitable here. Such a frame could include details about why the client was disconnected.

    Also, it's worth noting that STOMP only specifies support for generic destinations without regard for delivery semantics so speaking about a STOMP "topic" isn't technically accurate. Of course, implementors are free to provide the kinds of delivery semantics they want and if those semantics fit with traditional "topic" (i.e. publish/subscribe) semantics that's certainly permissible.