eventstream_promise.go

promise := eventStream.Subscribe()
for {
	select {
	case <-ctx.Done():
		return ctx.Err()
	case <-promise.Ready():
		v, nextPromise := promise.Next()
		if v == nil {
			return nil
		}
		promise = nextPromise
		msg := v.(bwamp.Event)
		// [Send msg to client]
	}
}