Url Shortener (AngularJS service using Google UrlShortener API)

url_shortener.coffee

angular.module('AppServices')
  .factory 'UrlShortener', ($q, $rootScope) ->
    gapiKey = 'APP_KEY'
    gapi_deferred = $q.defer()
    gapi_loaded = gapi_deferred.promise
    
    gapi.client.setApiKey(gapiKey)
    gapi.client.load 'urlshortener', 'v1', ->
      $rootScope.$apply ->
        gapi_deferred.resolve('loaded')

    {
      expand: (short_url, callback) ->
        gapi_loaded.then ->
          request = gapi.client.urlshortener.url.get
            'shortUrl': short_url
          request.execute (response) ->
            callback(response.longUrl)

      shorten: (url) ->
        short_url_deffered = $q.defer()
        gapi_loaded.then ->
          request = gapi.client.urlshortener.url.insert
            'resource': 
              'longUrl': url
          request.execute (response) ->
            $rootScope.$apply ->
              short_url_deffered.resolve(response.id)
        short_url_deffered.promise
    }