Nginx日志切割，跨域配置，防盗链配置

add_header 'Access-Control-Allow-Origin' $http_origin;
add_header 'Access-Control-Allow-Credentials' 'true';
add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
add_header 'Access-Control-Allow-Headers' 'DNT,web-token,app-token,Authorization,Accept,Origin,Keep-Alive,User-Agent,X-Mx-ReqToken,X-Data-Type,X-Auth-Token,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range';
add_header 'Access-Control-Expose-Headers' 'Content-Length,Content-Range';
if ($request_method = 'OPTIONS') {
add_header 'Access-Control-Max-Age' 1728000;
add_header 'Content-Type' 'text/plain; charset=utf-8';
add_header 'Content-Length' 0;
return 204;

}

server {
   listen 80;
   server_name www.imcati.com refer-test.imcati.com;
   root /usr/share/nginx/html;
   location ~*.(gif|jpg|jpeg|png|bmp|swf)$ {
        valid_referers none blocked www.imcati.com;
        if ($invalid_referer) {
            return 403;
           }
      }
   }

valid_referers: 指定资源访问是通过以下几种方式为合法，即白名单。
none：允许缺失的头部访问。
blocked：允许referer没有对应值的请求。
server_names：若referer站点域名与server_name中本机配的域名一样允许访问。