wrappedResource.js

var wrappedResourceMethods = [
  'get', 'query'
];

var wrappedResource = function (resource) {
  _.each(wrappedResourceMethods, function (method) {
    if (_.has(resource, method)) {
      var originalMethod = resource[method];
      resource[method] = function () {
        var result = originalMethod.apply(this, arguments);
        result.is_loading = true;

        if (result.$promise) {
          result.$promise.then(function () {
            result.is_loading = false;
          });
        }

        return result;
      };
    }
  });
  return resource;
};

YourAppServices.factory('service', ['$resource', 'API_ENDPOINT',
    function($resource){
        return wrappedResource($resource('url'...