We are using the Undertow SSE support.

In the SSE spec, it is possible to send a "retry: <time in milliseconds>" that tells the client to try a reconnection after a certain amount of time (https://html.spec.whatwg.org/multipage/comms.html#concept-event-stream-reconnection-time).

Right now, we haven't found the ability to send the "retry" via the Undertow API. 

If we look at the ServerSentEventConnection class, you can only send an event, an id and a data.

So, is it a missing feature or is there a way, we may have missed, to send the "retry"?

Thanks in advance for the answer!

Best regards,

Cédric.