[j0hnik]

getRequest: function(link) {
    var $this = this;
    var request = new XMLHttpRequest();
    request.open('GET', link , true)
    request.onreadystatechange = function(e) {
      if (this.readyState == 4) {
        if(this.status == 200) {
          var response = JSON.parse(this.responseText);
          console.log(response);
          $this.showWeatherData(response);
          }
        }
      }
    request.send(null);
  },

так например