code: func (db *Dashboard) sendToAll(msg *Message) {
  	db.lock.Lock()
  	for _, c := range db.conns {
  		select {
  		case c.msg <- msg:
  		default:
  			c.conn.Close()
  		}
  	}
  	db.lock.Unlock()
  }
docs: // sendToAll sends the given message to the active dashboards.