How to send a variable to a NodeJS controller from an AngularJS service?

I have an AngularJS service called sensorReadingsAPI, which has the following function with get:

var _countSensorReadingsFilter = function () {
  return $http.get(config.baseUrl + "/sensorReading/countFilter").then(function (data,status) {
    sensorReadingCountFilter = data.data;
    return Number(sensorReadingCountFilter);
  }).catch(function() {});
};

The /countFilter is defined in a NodeJS controller:

module.exports = {
  countFilter: function (req, res) {
    return res.sensorReadingCountFilter();
  }
};

And sensorReadingCountFilter is as follows:

module.exports = function sensorReadingCountFilter(statusCode){

  var req = this.req;
  var res = this.res;

  SensorReading.count({deviceNum:'MBA002'}).exec(function countCB(error, found) {
    return res.view({val: found});
  });
};

Right now, the count is static (where is written {deviceNum:'MBA002'}). I need a way to make this value be dinamic, using a variable, preferably being send from the AngularJS controller. I have several devices, with the portential to add even more, and don't want to create a /countFilter module for each of them.

In other words, a way to send variables from an AngularJS service to a NodeJS controller. When searching for ways to do this, I have found next to nothing.

For clearance: all of this returns the number of readings from the selected device, and config.baseUrlis the local machine and port.

via Ernani