A way to handle auth redirects for rails + angular

app.coffee

_(angular.module("app", [])).tap (app) ->
  app.config ['$httpProvider', ($httpProvider) ->
        # csrf header
        $httpProvider.defaults.headers.common["XSRF-TOKEN"] = "inject token here"
        # all the requests are XHR!
        $httpProvider.defaults.headers.common["X-Requested-With"] = 'XmlHttpRequest'
        # to handle 401s from rails
        $httpProvider.responseInterceptors.push(cep.ng.interceptors.BroadcastSessionExpiredOn401)
    ]

broadcast_session_expired_on_401.coffee

def 'cep.ng.interceptors.BroadcastSessionExpiredOn401',
  ($rootScope, $q) ->
    success = (response) -> response
    error   = (response) ->
      if response.status is 401
        deferred = $q.defer()
        req =
          config: response.config
          deferred: deferred
        $rootScope.$broadcast('session:expired')
        deferred.promise
      $q.reject(response)
    (promise) -> promise.then(success, error)