gobwas-ws clean conn close - go

Question

I use high-level structures to create a ws server.
func wsHandler(w http.ResponseWriter, r *http.Request) {
re := regexp.MustCompile(`^\/ws\/([0-9a-zA-Z]+)\/*`)
match := re.FindStringSubmatch(r.URL.Path)
if len(match) != 2 {
http.NotFound(w, r)
return
}
conn, _, _, err := ws.UpgradeHTTP(r, w)
if err != nil {
log.Printf("gobwas/ws: %s", err)
}
go func() {
defer conn.Close()
channels.Lock()
channels.Channels[match[1]] = append(channels.Channels[match[1]], &conn)
channels.Unlock()
for {
msg, op, err := wsutil.ReadClientData(conn)
if err != nil {
if err != io.EOF {
log.Printf("gobwas/ws/wsutil: %s", err)
}
break
}
if len(msg) > 0 {
go sendMessage(&conn, op, match[1], msg)
}
}
deleteConn(&conn, match[1])
}()
}
Then, when I implement a graceful disconnection, then with the usual conn.Close (), the connection simply breaks outside the protocol. I use the following code to close:
func onShutdown() {
channels.RLock()
for _, channel := range channels.Channels {
for _, conn := range channel {
if err := ws.WriteFrame(*conn, ws.NewCloseFrame(ws.NewCloseFrameBody(ws.StatusNormalClosure, "Server shutdown"))); err != nil {
fmt.Println(err)
}
(*conn).Close()
}
}
channels.RUnlock()
}
And even if I wait for a response from the client and then close the connection, then anyway, the client fixes the disconnection. (The client is the browser and JS WebSocket).
Sample JS code:
var socket = new WebSocket(`${location.protocol === "https:" ? "wss:" : "ws:"}//${window.location.host}/ws/valid`);
socket.onclose = function (event) {
if (event.wasClean) {
console.log('Clean');
} else {
console.log('disconnect');
}
console.log('Code: ' + event.code + ' reason: ' + event.reason);
};