nginx 设置允许跨域请求

参考1：https://developer.mozilla.org/zh-CN/docs/Web/HTTP/Access_control_CORS

参考2：http://www.ruanyifeng.com/blog/2016/04/cors.html

server {
        listen       8080;
        server_name  localhost;
        #charset koi8-r;
        #access_log  logs/host.access.log  main;
        add_header 'Access-Control-Allow-Methods' 'GET,OPTIONS,POST' always;
        add_header 'Access-Control-Allow-Credentials' 'true' always;
        add_header 'Access-Control-Allow-Origin' $http_origin always;
        add_header 'Access-Control-Allow-Headers' 'Authorization, Content-Type, X-Requested-With, Cache-Control' always;
        if ($request_method = OPTIONS ) { return 200; }

        location / {
           root   html;
           index  index.html index.htm;
           add_header 'Access-Control-Allow-Methods' 'GET,OPTIONS,POST' always;
            add_header 'Access-Control-Allow-Credentials' 'true' always;
            add_header 'Access-Control-Allow-Origin' $http_origin always;
            add_header 'Access-Control-Allow-Headers' 'Authorization, Content-Type, X-Requested-With, Cache-Control' always;
            if ($request_method = OPTIONS ) { return 200; }

        }
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }
    }