如何进行跨域配置

nginx跨域配置

配置参考1

location / {
    add_header 'Access-Control-Allow-Origin' '*' always;
    add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS' always;
    add_header 'Access-Control-Allow-Credentials' 'true' always;    
}        

配置参考2

location / { 
     add_header "Access-Control-Allow-Origin" *; 
     add_header "Access-Control-Allow-Methods" "GET, POST, OPTIONS"; 
     add_header "Access-Control-Allow-Headers" "Authorization"; 
}

配置参考3，只支持某个来源的域名跨域

location / { 
     add_header "Access-Control-Allow-Origin" 'vivo.com.cn'; 
     add_header "Access-Control-Allow-Methods" "GET, POST, OPTIONS"; 
     add_header "Access-Control-Allow-Headers" "Authorization"; 
}

注意点

nginx如果配置了跨域配置，则后端服务无需配置改配置。如果有多层nginx，则只需要有一层nginx配置了该配置即可。同理，如果服务端（flask/django等）配置了跨域，则nginx无需此配置。

否则会出现以下错误：The 'Access-Control-Allow- Origin' header contains multiple values '*, *', but only one is allowed

http://api-ai.vivo.com.cn/bosum/homeworkFilter	Default levels	1ss	
Access to XMLHttpRequest at 'http://api-ai.vivo.com.cn/bosum/homework correct'from origin 'http://localhost:9532' has been blocked by CORS p policy: Response to preflight request doesn't pass access control check: The 'Access-Control-Allow- Origin' header contains multiple values '*, *', but only one is allowed. POST http://api-ai.vivo.com.cn/bosum/homework correct net::ERR_FAILED

flask跨域配置

配置全局跨域配置或者单个路由支持跨域：https://blog.csdn.net/qq_38161040/article/details/123994884

测试工具

如何测试自己的接口是否支持跨域

1.在线测试网站：https://cors-test.codehappy.dev

2.浏览器测试方法：https://developer.aliyun.com/article/688172

var xhr = new XMLHttpRequest();
xhr.open('GET', 'https://www.xxx.com/api/action');
xhr.send(null);
xhr.onload = function(e) {
    var xhr = e.target;
    console.log(xhr.responseText);
}

3.curl命令测试响应头是否是否支持跨域：https://tecadmin.net/how-to-enable-cors-in-nginx/

curl -v http://your_domain.com