Nginx OPTIONS过滤配置

前后端分离开发，POST请求先请求OPTIONS 试探请求响应

if ($request_method = 'OOPTIONS') {
                                add_header 'Access-Control-Allow-Origin' '*';
                                add_header 'Access-Control-Allow-Origin' 'http://localhost:9528';
                                add_header 'Access-Control-Allow-Credentials' true;
                                #
                                # Custom headers and headers various browsers *should* be OK with but aren't
                                #
                                add_header 'Access-Control-Allow-Headers' 'CJCX,cjcx,DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';
                                #
                                # Tell client that this pre-flight info is valid for 20 days
                                #

                                add_header 'Access-Control-Max-Age' 1728000;
                                add_header 'Content-Type' 'text/plain charset=UTF-8';
                                add_header 'Content-Length' 0;
                                return 204;
                }