Errors, stopping and signing out

A command that fails throws a db.CommandError, with the server's message and a status:

Status	When
400	the server cannot use the payload, a value or the query
401	there is no valid token
403	the user may not do this, for example when `CmsApiOptions.Authorize` refuses or a module is not active
404	the node does not exist
409	a conflict, such as a second published revision in one culture
499	the call was stopped through its signal; `cancelled` is set
500	anything else

Every method that sends a command takes an AbortSignal last. Aborting it also stops the command on the server:

let running: AbortController | null = null;
async function suggest(text: string) {
  running?.abort();                                        // the user typed again
  running = new AbortController();
  return store.query(Page).where(n => n.Name.startsWith(text)).take(10).execute(running.signal);
}

channel.onUnauthorized(handler) is called when the server refuses the token, because it expired or its user was deleted. Sign in again, then call channel.connect() to open the stream again.