离子与铁轨的CORS问题

我正在尝试使用ionic和后端的示例项目Rails.当我使用离子服务启动离子服务器并提交我的样本表格时

XMLHttpRequest cannot load http://localhost:3000/signup. Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:8100' is therefore not allowed access. The response had HTTP status code 404.

尝试了我在谷歌得到的一些答案,但无法得到它.下面是我的app.js代码index.html和ionic.project文件代码.

angular.module('starter', ['ionic'])

.run(function($ionicPlatform) {
  $ionicPlatform.ready(function() {
    if(window.cordova && window.cordova.plugins.Keyboard) {
      cordova.plugins.Keyboard.hideKeyboardAccessoryBar(true);
      cordova.plugins.Keyboard.disableScroll(true);
    }
    if(window.StatusBar) {
      StatusBar.styleDefault();
    }
  });
})

.constant('ApiEndpoint',  'http://localhost:3000/')

.config(function($stateProvider, $urlRouterProvider) {
  $stateProvider
  .state('signUp',{
    cache: false,
    url: "/signUp",
    templateUrl: "templates/signUp.html",
    controller: 'ExampleCtrl'
  }) 

  $urlRouterProvider.otherwise("/signUp");
})

.controller('ExampleCtrl', ['$scope','$http','ApiEndpoint', function ($scope, $http, ApiEndpoint) {

  $scope.registrationForm = {};

  $scope.signUp = function(){
    console.log($scope.registrationForm);
    console.log(ApiEndpoint);
     $http.post(ApiEndpoint + "signup", {a: 1}).then(function(result){
       console.log(result);
       $scope.registrationForm = {};
     }, function(error){
       console.log(error);
       $scope.registrationForm = {};
     })
  }
}])




  
    
    
    

    
    

    

    
    

    
    

    
    
  
  
    
      
        
      
      
      
    
  



{
  "name": "kranthi_web",
  "app_id": "",
  "proxies": [
    {
      "path": "/api",
      "proxyUrl": "http:localhost:3000/"
    }
  ]
}

有人能告诉我,我在哪里做错了

CORS(跨源资源共享)策略旨在防止对不同域资产的XML请求.

基本上,如果您通过XML从不同的域/服务器请求资源,则需要确保在该服务器上具有相应的CORS策略来处理它.

默认情况下,Rails会阻止响应任何外部XML请求.解决这个问题的唯一方法是通过自己的CORS策略来允许资源.

该rack-cors宝石是最好的这样:

#config/application.rb
# ...

config.middleware.insert_before 0, "Rack::Cors" do
  allow do
    origins '*'
    resource '*', :headers => :any, :methods => [:get, :post, :options]
  end
end

如果您为您的域(IE localhost或其他)设置了上述内容,您应该能够从前端JS访问您的后端.

...并且记住使用Angular /其他JS类型框架,您将每次都发送XML请求.