devices.on

The best thing about Grandeur is the fact that it is event driven. Means you can subscribe to events and we will automatically send you an alert whenever the subscribed event will occur. This methods allows you to subscribe to event related to devices list update. An event will be fired whenever a device gets paired or unpaired to a user account.

This method accepts the following arguments

This method returns the following codes in the response to the promise

TOPIC-SUBSCRIBED

event has been subscribed

It is important to note that the update will be directly sent without a response code. So for example whenever a new device will be paired, entire list will be sent as the argument in form an array.

The call to this method also returns reference to a clear method with which you can unsubscribe to the event. It don't accept anything in the argument and returns the following code as a response to promise

TOPIC-UNSUBSCRIBED

event has been unsubscribed and update won't trigger the callback provided earlier

The use of this method has been illustrated in the example below

// Variable to store clear method of subscribed event
var listener = null;
 
// Function to be passed as a callback
var onUpdate = (update) {
  // Will be called whenever the
  // event will be fired
  console.log(update);
};
 
// Subscribe to the devices list update event of a device
devices.on(onUpdate).then((res) => {
  // Call to onDevicesList returns the
  // clear method as a response to promise 
  switch(res.code) {
    case "TOPIC-SUBSCRIBED": 
      // Event has been subscribed
      listener = res;
  }
});
  
 
// Then in our code we can clear the event 
// listener whenever required with the clear method
listener.clear().then((res) => {
  // Got the response
  switch(res.code) {
    case "TOPIC-UNSUBSCRIBED": 
      // Event has been unsubscribed
  }
});