docs: function update(client) {
    var id = client.id;
  
    // Auto-remove when this client is closed.
    client.once('closed', function() {
      remove(id);
    });
  
    var info = find(client);
    if(!info) {
      log.warn('No ClientInfo object found for client.id=%s', id);
      return;
    }
    info.username = client.username;
  }