gistfile1.txt

server {
    listen 80;
    server_name localhost;
    root /home/app/public;

    passenger_enabled on;
    passenger_user app;

    passenger_sticky_sessions on;

    passenger_app_type node;
    passenger_startup_file main.js;

    location / {
        try_files $uri @prerender;
    }

    location @prerender {
        proxy_set_header X-Prerender-Token fake;

        set $prerender 0;
        if ($http_user_agent ~* "baiduspider|twitterbot|facebookexternalhit|rogerbot|linkedinbot|embedly|quora link preview|showyoubot|outbrain|pinterest") {
            set $prerender 1;
        }
        if ($args ~ "_escaped_fragment_") {
            set $prerender 1;
        }
        if ($http_user_agent ~ "Prerender") {
            set $prerender 0;
        }
        if ($uri ~ "\.(js|css|xml|less|png|jpg|jpeg|gif|pdf|doc|txt|ico|rss|zip|mp3|rar|exe|wmv|doc|avi|ppt|mpg|mpeg|tif|wav|mov|psd|ai|xls|mp4|m4a|swf|dat|dmg|iso|flv|m4v|torrent)") {
          set $prerender 0;
        }

        if ($prerender = 1) {
            rewrite .* /$scheme://example.com$request_uri? break;
            proxy_pass http://service.prerender.io;
        }
        if ($prerender = 0) {
            rewrite .* / break;
        }
    }

}