prerender-解决JavaScript SEO

const prerender = require('prerender');
const server = prerender();
server.start();

server {
    listen       80;
    server_name  example.com;

    charset utf8;
    location / {
        try_files $uri @prerender;
    }

    location @prerender {
        # 自己部署的 prerender 服务不需要这个参数
        proxy_set_header X-Prerender-Token YOUR_TOKEN;
        
        set $prerender 0;
        if ($http_user_agent ~* "googlebot|bingbot|yandex|baiduspider|twitterbot|facebookexternalhit|rogerbot|linkedinbot|embedly|quora link preview|showyoubot|outbrain|pinterest\/0\.|pinterestbot|slackbot|vkShare|W3C_Validator|whatsapp") {
            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|ttf|woff|svg|eot)") {
            set $prerender 0;
        }

        # 自定义哪些路径需要渲染，哪些不需要
        if ($uri !~ ^/main/(.*)$) {
            set $prerender 0;
        }
        
        # DNS解析，使后面的请求能直接访问源站，不然会一直请求到nginx，导致循环
        resolver 114.114.114.114 8.8.8.8;

        if ($prerender = 1) {
            
            #setting prerender as a variable forces DNS resolution since nginx caches IPs and doesnt play well with load balancing
            set $prerender "127.0.0.1:3300";
            rewrite .* /$scheme://$host$request_uri? break;
            proxy_pass http://$prerender;
        }
        if ($prerender = 0) {
            proxy_pass $scheme://$host;
        }
    }

}