cors.conf

     set $var_cors 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range,X-app-language,X-app-version,X-app-countr';

     if ($request_method = 'OPTIONS') {
        add_header 'Access-Control-Allow-Origin' '*';
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
         add_header 'Access-Control-Allow-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range,X-app-language,X-app-version,X-app-country';
        add_header 'Access-Control-Max-Age' 1728000;
        add_header 'Content-Type' 'text/plain charset=UTF-8';
        add_header 'Content-Length' 0;
        return 204;
     }
     if ($request_method = 'POST') {
        add_header 'Access-Control-Allow-Origin' '*' always;
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS' always;
        add_header 'Access-Control-Allow-Headers' $var_cors always;
        add_header 'Access-Control-Expose-Headers' $var_cors  always;
     }
     if ($request_method = 'GET') {
        add_header 'Access-Control-Allow-Origin' '*' always ;
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS' always ;
        add_header 'Access-Control-Allow-Headers' $var_cors  always;
        add_header 'Access-Control-Expose-Headers' $var_cors  always;
     }