maybe a concurrency problem?

[Summuss]

When following two statements of m.readChs.Store(m.ID, readerCh) run conrrently, will any readerCh be override by the other with the same m.Id? If so the readerCh overrided won't be able to receive message.

// ListDaemons lists all active daemons.
func (m *Daemon) ListDaemons(ctx context.Context, in *proto.ListDaemonsInput) (out *proto.ListDaemonsOutput, err error) {
        //segment1
	readerCh := make(chan *types.WebsocketMessage)
	m.readChs.Store(m.ID, readerCh)
	m.writeCh <- &types.WebsocketMessage{
		Action:  types.ActionListDaemonsRequest,
		UserID:  m.ID,
		Message: "list active daemons",
	}
//.........
}

case <-m.forceUpdate:
	log.Println("received force status updates")
        //segment2
	readerCh := make(chan *types.WebsocketMessage)
	m.readChs.Store(m.ID, readerCh)

[changkun]

m.ID is guaranteed to be globally unique.

[Summuss]

For one daemon instance, m.readChs.Store(m.ID, readerCh) in rpc service and that in watchOfficeStatus would have the same m.ID. Is that so?

[changkun]

Yes, I think so.

[changkun]

Are you thinking that if readerCh was overwritten then the ListDaemon, for instance, will block forever?

[Summuss]

Yes, I‘m afraid of that situation.

[changkun]

I evaluated the case, and I think you are right, a patch to fix the issue is on the way. Thanks a lot for the report.