How can I mock and unit test the following AngularJS Factories using karma/jasmin -

 have angular factory again calls factory-  service  uses $resource api call.  tell me, how can mock , test kind of  constructs. 

//factory      angular.module('myapp')         .factory('samplef', function (samples) {             return {                 getdata: function (parm, callback) {                     var cb = callback || angular.noop;                      return samples.get(parm,                         function (res) {                             return cb(res);                         },                         function (err) {                             return cb(err);                         }.bind(this)).$promise;                 }             };         });   // service: samples          angular.module('myapp')         .factory('samples', function ($resource) {             return $resource('http://localhost:8080:/api/sample/:parm', {                 parm: '@parm',             }, {});         });  //api response  `          {             "firstname": "john",             "lastname": "franklin",             "companyname": "benton, john b jr",             "address": "6649 n blue gum st",             "city": "new oakland",             "county": "oakland",             "statie": "la",             "zip": "703333",             "phone": "503-321-2227",             "phone2": "514-145-427",             "email": "john@gmail.com",          } 

describe('test',function(){      beforeeach(module('myapp'));     var samplef,myapp,     beforeeach(inject(function(_samplef_,_myapp_){         samplef=_samplef_;         myapp=_myapp_;     }));     it('testing'function(){         //here can call function , expect values     });  });