How to solve the problem of cookie loss during Ajax cross-domain access

This time I will bring you how to solve the problem of cookie loss during Ajax cross-domain access. What are the precautions ? The following is a practical case. Let’s take a look. Ajax cross-domain access can be achieved using the jsonp method or setting Access-Control-Allow-Origin. Regarding setting Access-Control-Allow-Origin to achieve cross-domain access, you can refer to the article I wrote before "ajax setting Access -Control-Allow-Origin to achieve cross-domain access》

1.ajax cross-domain access, cookie lossFirst create two test domain names

a.fdipzone.com as the client domain name

b.fdipzone.com as the server domain name

Test code

setcookie.PHP is used to set Server cookie

<?php setcookie(&#39;data&#39;, time(), time()+3600);
?>

server.php is used to be requested by the client

<?php $name = isset($_POST[&#39;name&#39;])? $_POST[&#39;name&#39;] : &#39;&#39;;
$ret = array(
 &#39;success&#39; => true,
 'name' => $name,
 'cookie' => isset($_COOKIE['data'])? $_COOKIE['data'] : ''
);
// 指定允许其他域名访问
header('Access-Control-Allow-Origin:http://a.fdipzone.com');
// 响应类型
header('Access-Control-Allow-Methods:POST'); 
// 响应头设置
header('Access-Control-Allow-Headers:x-requested-with,content-type');
header('content-type:application/json');
echo json_encode($ret);
?>

test.html Client request page

nbsp;HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

 
 <meta>
 <script></script>
 <title> ajax 跨域访问cookie丢失的解决方法 </title>
 
 
 <script>
 $(function(){
  $.ajax({
   url: &#39;http://b.fdipzone.com/server.php&#39;, // 跨域
   dataType: &#39;json&#39;,
   type: &#39;post&#39;,
   data: {&#39;name&#39;:&#39;fdipzone&#39;},
   success:function(ret){
    if(ret[&#39;success&#39;]==true){
     alert(&#39;cookie:&#39; + ret[&#39;cookie&#39;]);
    }
   }
  });
 })
 </script>
 

First execute http://b.fdipzone .com/setcookie.php, creates a server-side cookie.

Then execute http://a.fdipzone.com/test.html

Output

{"success":true,"name":"fdipzone","cookie":""}

Failed to obtain cookie.

2. Solution

Client

Set the withCredentials attribute to true when requesting

Enables you to specify that credentials should be sent for a certain request. If the server receives a request with credentials, it will respond with the following HTTP headers.

Server

Set header

header("Access-Control-Allow-Credentials:true");

Allow requests with verification information

test.html Modify as follows

nbsp;HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

 
 <meta>
 <script></script>
 <title> ajax 跨域访问cookie丢失的解决方法 </title>
 
 
 <script>
 $(function(){
  $.ajax({
   url: &#39;http://b.fdipzone.com/server.php&#39;, // 跨域
   xhrFields:{withCredentials: true}, // 发送凭据
   dataType: &#39;json&#39;,
   type: &#39;post&#39;,
   data: {&#39;name&#39;:&#39;fdipzone&#39;},
   success:function(ret){
    if(ret[&#39;success&#39;]==true){
     alert(&#39;cookie:&#39; + ret[&#39;cookie&#39;]);
    }
   }
  });
 })
 </script>
 

server.php is modified as follows

<?php $name = isset($_POST[&#39;name&#39;])? $_POST[&#39;name&#39;] : &#39;&#39;;
$ret = array(
 &#39;success&#39; => true,
 'name' => $name,
 'cookie' => isset($_COOKIE['data'])? $_COOKIE['data'] : ''
);
// 指定允许其他域名访问
header('Access-Control-Allow-Origin:http://a.fdipzone.com');
// 响应类型
header('Access-Control-Allow-Methods:POST'); 
// 响应头设置
header('Access-Control-Allow-Headers:x-requested-with,content-type');
// 是否允许请求带有验证信息
header('Access-Control-Allow-Credentials:true');
header('content-type:application/json');
echo json_encode($ret);
?>

Follow the previous steps and the request returns

{"success":true,"name":"fdipzone","cookie":"1484558863"}

Getting the cookie successfully

3. Notes1. If the client sets the withCredentials attribute to true, but the server does not set Access-Control-Allow-Credentials:true, an error will be returned during the request.

XMLHttpRequest cannot load http://b.fdipzone.com/server.php. Credentials flag is 'true', but the 'Access-Control-Allow-Credentials' header is ''. It must be 'true' to allow credentials. Origin 'http://a.fdipzone.com' is therefore not allowed access.

2. After the server header sets Access-Control-Allow-Credentials: true, Access-Control-Allow-Origin cannot be set to * and must be set to a domain name, otherwise an error will be returned.

XMLHttpRequest cannot load http://b.fdipzone.com/server.php. A wildcard '*' cannot be used in the 'Access-Control-Allow-Origin' heade

Let’s take a look at the solution to the problem that COOKIE cannot be brought with Ajax cross-domain requests

Native ajax request method:

var xhr = new XMLHttpRequest(); 
xhr.open("POST", "http://xxxx.com/demo/b/index.php", true); 
xhr.withCredentials = true; //支持跨域发送cookies
xhr.send();

jquery's ajax post method request:

 $.ajax({
    type: "POST",
    url: "http://xxx.com/api/test",
    dataType: 'jsonp',
    xhrFields: {
      withCredentials: true
    },
   crossDomain: true,
   success:function(){
  },
   error:function(){
 }
})

Server-side settings:

header("Access-Control-Allow-Credentials: true");
header("Access-Control-Allow-Origin: http://www.xxx.com");

I believe I read the case in this article You have mastered the method. For more exciting information, please pay attention to other related articles on the php Chinese website!

Recommended reading:

Using Ajax to implement registration and avatar upload functions

Detailed explanation of the steps for using ajax to implement paging technology (with code )

What is the difference between async:false and async:true in Ajax requests

The above is the detailed content of How to solve the problem of cookie loss during Ajax cross-domain access. For more information, please follow other related articles on the PHP Chinese website!