Handling command errors with JavaScript “Promise” feature

The use of the new JavaScript ‘Promise’ feature is encouraged to handle any request errors.

For example:

  okular.Reboot().then(function(result) {
    console.log(result); // Success: stuff worked!
}, function(err) {
    console.log(err);
    // Error: Maybe retry later.
});

This applies for several functions like:

okular.Beep(level),
okular.SetFrontlight(level),
okular.Sleep(periodMinutes),
okular.SetHeartbeat(minutes),
okular.TouchUpdate(),
okular.ConfigureBattery(tresholdOff, tresholdOn, [tresholdCount = 1]),
okular.SetVcom(vcomArray),
okular.SetDisplayID(displayID) and
okular.Reboot().