function(event) {

  var returns = {};
  // Retrieve device ID
  var deviceId = event.Tags.Name;
  var path = event.path;



    // Call Cloud to retrieve device properties

    var properties_url = 'https://mycloud/devices/' + deviceId + '/properties';

    var properties_data = Octave.Http.get(properties_url);

    var get_device_properties = JSON.parse(properties_data.content);



    // check last known device properties stored in Octave /iotcentral/properties stream
    var filter_string = "hash=='" + String(deviceId) + "'";

    var get_last_properties = Octave.Event.findOne('properties_streamId', {
      filter: String(filter_string)
    });





    if (get_last_properties != null) {
      // set last known properties to the retrieved values

      var last_properties = get_last_properties.elems;
     
    } else {
      // if no properties exist yet, initialize them with default values
      console.log("device has no properties");
      
      var last_properties = {
        "propertyA": valueA,
        "propertyB": valueB
      };
      returns["/mycompany/properties"] = [{
        "elems": last_properties,
        "hash": deviceId
      }];
    }



    // Construct the data payload to send to cloud



    var Payload = {
      "device": {
        "deviceId": deviceId
      },
      "measurements": event.elems
    };


    var postBody = JSON.stringify(Payload);

    // Construct the request Header
    var postHeaders = {
      'Content-Type': 'application/json'
    };


    var result = Octave.Http.post('https://mycloud/device/', postHeaders, postBody);

    var command_stream = "/mycompany/devices/" + deviceId + "/:command";



    // Send properties to the device command stream if properties have changed:

    if (last_properties != device_properties) {
      // save device properties to a Octave.Event.find(streamId, { filter: "" })
      returns["/mycompany/properties"] = [{
        "elems": device_properties,
        "hash": deviceId
      }];

      returns[command_stream] = [{
        "elems": {
          "virtual": {
            "propertyA": {
              "value": device_properties.propertyA},
            "propertyB": {
              "value": device_properties.propertyB},
          }
        }
      }]
    }

    return returns;
}