code: function init(app) {
      app.post('/api/v1/push/registration', 
      /**
      * register the device on the push Service
      *
      * @param req containing body JSON to pass as input.
      * @param res result of call is provided as JSON body data.
      * @param next function to invoke error handling.
      */
      function serviceCall(req, res, next) {
          Q(pushService.registerPushDevice(req.body)).then(res.json.bind(res), next).done();
      });
      app.post('/api/v1/push', 
      /**
      * posts push notification(s).
      *
      * @param req containing body JSON to pass as input.
      * @param res result of call is provided as JSON body data.
      * @param next function to invoke error handling.
      */
      function serviceCall(req, res, next) {
          Q(pushService.postPushNotification(req.body)).then(res.json.bind(res), next).done();
      });
      app.get('/api/v1/push/:uuid', 
      /**
      * gets push notification status.
      *
      * @param req containing body JSON to pass as input.
      * @param res result of call is provided as JSON body data.
      * @param next function to invoke error handling.
      */
      function serviceCall(req, res, next) {
          Q(pushService.fetchPushNotification(req.params.uuid)).then(res.json.bind(res), next).done();
      });
  }
docs: module providing direct access to push.
  
  registers a push target device.
  
  <p>
  The method attempts fetching an existing device using the metadata
  information given. This either works by providing a UUID or using
  heuristics based on information typically extracted using Cordova device
  plugin. The latter approach solves the potential problem when the client
  is uninstalled and reinstalled so that device local information is lost.
  </p>
  <p>
  If it finds one, that device is updated. Otherwise a new
  device is created and stored in the database.
  </p>
  @link [RelutionSDK Push APi](https://relution-io.github.io/relution-sdk/modules/_push_push_.html)
  @param app express.js application to hook into.