reverse-proxy - 公司代理后面的 Varnish 或鱿鱼反向代理

Question

如何配置 Varnish (或者如果有人可以提示我使用鱿鱼我很好)来缓存来自后端的请求，但通过 http_proxy 连接到后端

所以我尝试:

backend default {
    .host = "10.1.1.1";
    .port = "8080";
}

backend corp_proxy {
  .host = "proxy";
  .port = "8080";
}
sub vcl_recv {
    # Happens before we check if we have this in cache already.
    #
    # Typically you clean up the request here, removing cookies you don't need,
    # rewriting the request, etc.
    set req.backend_hint = corp_proxy;
    set req.url ="http://" + req.http.host + req.url;
}

Answer 1

Varnish(或其他 Web 缓存代理)根据与缓存相关的 header (如 Cache-Control )缓存请求。
不幸的是，许多 Web 应用程序没有正确设置这些 header 。所以我们应该使用更积极的方法来缓存一些众所周知的项目，例如图片，.js或 .css文件。
而且，这条线set req.url ="http://" + req.http.host + req.url;不需要，因为 Varnish 将请求按原样发送到您指定的后端。
这是我推荐的配置:

backend corp_proxy {
  .host = "proxy";
  .port = "8080";
}

sub vcl_recv {
  
  // Determine backend
  if ( req.http.host ~ ".example.com" ) {
    set req.backend_hint = corp_proxy;
    
    // Determine cacheable items
    if( req.url ~ "\.(css|js|jpg|jpeg|png|gif|ico) {
      unset req.http.Cookie;
      unset req.http.Cache-Control;
    }
  }
  
}

sub vcl_backend_response {
  
  if( bereq.http.host ~ ".example.com" ) {
    if (bereq.url ~ "\.(css|jsjpg|jpeg|png|gif|ico)") {
      set beresp.ttl = 20m; // I opt for 20 minutes of caching by your mileage may vary
  }

}