backend/service/RESTService.js
function(url) {
    let request = parseRequest(url);
    let resource = getRequestedResource(request);
    return resource.get(request)
      .then(returnGetResponse);

    function returnGetResponse(result) { // eslint-disable-line require-jsdoc
      return new RESTResponse(url, "GET", result);
    }
  }
function(url) {
    let request = parseRequest(url);
    let resource = getRequestedResource(request);
    return resource.get(request)
      .then(returnGetResponse);

    function returnGetResponse(result) { // eslint-disable-line require-jsdoc
      return new RESTResponse(url, "GET", result);
    }
  }
Handle GET request.
@param {string} url - Resource locator.
@return {Promise} A resource.