varnish 中的内置变量

req

repos

client

server

bereq

beresp

bereq

bereq.http.HEADER  由varnish发往backend server 的请求报文指定首部

bereq.request 请求方法

bereq.url

bereq.proto:  协议版本

beresp

bereq.proto

bereq.status:

bereq.backend.ip

beresp.backend.name

beresp.http.HEADER  从backend server 响应报文指定首部

bereq.ttl 后端服务器响应的内容的余下的生存时长；

官方文档
http://www.varnish-cache.org/trac/wiki/VCLExampleDirector

支持虚拟主机：

    if (req.http.host == "www.fengpic.com") {

    }

强制对某些资源的请求，不检查缓存：

/admin

/login

    if (req.url ~ "(?i)^/login" || req.url ~ "(?i)^/admin") {

        return(pass)

    }

test.html

    if (req.url ~ "(?i)test.html$") {

        return(pass)

    }

sub vcl_recv{
　　if (req.url ~"(?i)\.(jpg|png|gif)$") {
　　　　set req.backend_hint = "fdfs_g1_s1"
　　else {
　　　　set req.backend_hint = "fdfs_g1_s2"
　　　　}
　　}

对域名进行缓存

sub vcl_recv {
　　if (req.http.host ~ "^(ww.)?example.com%") {
　　　　set req.backend_hint = vdir1.backend();
　　} 
}

对多个group进行缓存

backend fdfs_g1_s1 {
.host = "192.168.20.151";
.port = "8080";
.probe = {
.url = "/";
.timeout = 1s;
.interval = 10s;
.window = 5;
.threshold = 2;
}
}

backend fdfs_g1_s2 {
.host = "192.168.20.152";
.port = "8080";
.probe = {
.url = "/";
.timeout = 1s;
.interval = 10s;
.window = 5;
.threshold = 2;
}
}

backend fdfs_g2_s1 {
.host = "192.168.20.153";
.port = "8080";
.probe = {
.url = "/";
.timeout = 1s;
.interval = 10s;
.window = 5;
.threshold = 2;
}
}

backend fdfs_g2_s2 {
.host = "192.168.20.154";
.port = "8080";
.probe = {
.url = "/";
.timeout = 1s;
.interval = 10s;
.window = 5;
.threshold = 2;
}
}

sub vcl_init {
new vdir1 = directors.round_robin();
vdir1.add_backend(fdfs_g1_s1);
vdir1.add_backend(fdfs_g1_s2);

new vdir2 = directors.round_robin();
vdir2.add_backend(fdfs_g2_s1);
vdir2.add_backend(fdfs_g2_s2);

return (ok);
}

sub vcl_recv {
　　if (req.url ~ "($i)^/group1") {
　　　　set req.backend_hint = vdir1.backend();
　　}
　　if (req.url ~ "($i)^/group2") {
　　　　set req.backend_hint = vdir2.backend();
　　}
}

首先是必须定义版本号： vcl 4.0。VMOD’s更独立化，官方推荐是加载Standard VMOD’s（std）。

另外director已变为VMOD，如需使用，需要import directors。

vcl_fetch函数被vcl_backend_response和vcl_backend_fetch代替，且req.*不再适用vcl_backend_response，只能使用bereq.*。

至于vcl_backend_fetch貌似没哪个doc见到详细用法。

error变更为return(synth(http_code,message))，req.backend成了req.backend_hint，req.request变更为req.method，obj为只读对象了。

vcl_synth采用resp.*，而非原来的obj.*。

vcl_error变更为vcl_backend_error，必须使用beresp.*，而不是obj.*。

关键字"purge;"命令，已被去除。在vcl_recv使用return(purge)。

hit_for_pass通过set beresp.uncacheable = true;来指定。

vcl_recv必须将lookup变更返回hash，vcl_hash必须将hash变更返回lookup，vcl_pass必须将pass变更返回fetch。

req.backend.healty被std.healthy(req.backend)代替，但是设置不了grace，鸡肋，被抛弃了，现在仅能做的就是keepalive的作用了。

req、bereq，resp、beresp之间不同，可被使用的位置不同。

server.port、client.port分别变更为std.port(server.ip)、std.port(client.ip)，跟上面healthy一样，需要import std。

session_linger变更为timeout_linger，sess_timeout变更为timeout_idle，sess_workspace被抛弃了。

remove被完全弃用了，不过我一直用unset的说。

return(restart)变更为return(retry)，vcl_backend_fetch会被使用到。

自定义sub函数不能以vcl_开头，调用方式call udf。

 vcl 4.0;

 import std;

 import directors;

 backend fdfs_g1_s1 {

      .host = "192.168.20.151";

      .port = "";

      .probe = {

         .url = "/";

         .timeout   = 1s;

         .interval  = 10s;

         .window    = ;

         .threshold = ;

     }

 }

 backend fdfs_g1_s2 {

      .host = "192.168.20.152";

      .port = "";

      .probe = {

         .url = "/";

         .timeout   = 1s;

         .interval  = 10s;

         .window    = ;

         .threshold = ;

     }

 }

 acl purgers {

     "localhost";

     "127.0.0.1";

 }

 sub vcl_init {

     new vdir = directors.round_robin();

     vdir.add_backend(fdfs_g1_s1);

     vdir.add_backend(fdfs_g1_s2);

     return (ok);

 }

 sub vcl_recv {

      set req.backend_hint = vdir.backend();

      if (req.http.x-forwarded-for) {

          set req.http.X-Forwarded-For = req.http.X-Forwarded-For + ", " + client.ip;

      } else {

          set req.http.X-Forwarded-For = client.ip;

      }    

      if (req.method == "PURGE") {    # PURGE请求的处理

         if (!client.ip ~ purgers) {

             return(synth(,"Method not allowed"));

         }

         #清理缓存

         return (purge);

      }

      # 禁止缓存的文件

      if (req.url ~ "\.(php|jsp|do|cgi)$") {

         return (pass);

      }

      if (req.method == "PRI") {

         #/* We do not support SPDY or HTTP/2.0 */

         return (synth());

      }

      if (req.method != "GET" &&

        req.method != "HEAD" &&

        req.method != "PUT" &&

        req.method != "POST" &&

        req.method != "TRACE" &&

        req.method != "OPTIONS" &&

        req.method != "DELETE") {

          #/* Non-RFC2616 or CONNECT which is weird. */

          return (pipe);

      }

      if (req.method != "GET" && req.method != "HEAD") {

          #/* We only deal with GET and HEAD by default */

          return (pass);

      }

      if (req.http.Authorization || req.http.Cookie) {

          #/* Not cacheable by default */

          return (pass);

      }

      return (hash);

 }

 sub vcl_backend_response {

     if (beresp.http.cache-control !~ "s-maxage") {

         if (bereq.url ~ "\.(gif|jpeg|jpg|png)$") {

         set beresp.ttl = 3600s;

         unset beresp.http.set-cookie;

         }    

         if (bereq.url ~ "\.(css|js)$") {

         set beresp.ttl = 600s;

         unset beresp.http.set-cookie;

         }    

         if (bereq.url ~ "^[^?]*\.(7z|avi|bz2|flac|flv|amr|gz|mka|mkv|mov|mp3|mp4|mpeg|mpg|ogg|ogm|opus|rar|tar|tgz|tbz|txz|wav|webm|xz|zip)(\?.*)?$") {

         unset beresp.http.set-cookie;

         set beresp.do_stream = true;

         set beresp.do_gzip = false;

         }

     } else {

         if (beresp.ttl > 0s) {

             unset beresp.http.Set-Cookie;

         }

    }

     if (beresp.ttl <= 0s || beresp.http.Set-Cookie || beresp.http.Surrogate-control ~ "no-store" || (!beresp.http.Surrogate-Control && beresp.http.Cache-Control ~ "no-cache|no-store|private") || beresp.http.Vary == "*") {

         set beresp.ttl = 120s;

         set beresp.uncacheable = true;

     }

     return (deliver);

 }

 sub vcl_backend_fetch {

     return (fetch);

 }

 sub vcl_pipe {

      # By default Connection: close is set on all piped requests, to stop

      # connection reuse from sending future requests directly to the

      # (potentially) wrong backend. If you do want this to happen, you can undo

      # it here.

      # unset bereq.http.connection;

      return (pipe);

 }

 sub vcl_pass {

      return (fetch);

 }

 sub vcl_hash {

      hash_data(req.url);

      if (req.http.host) {

          hash_data(req.http.host);

      } else {

          hash_data(server.ip);

      }

      return (lookup);

 }

 sub vcl_purge {

      return (synth(, "Purged"));

 }

 sub vcl_hit {

      if (obj.ttl >= 0s) {

          #// A pure unadultered hit, deliver it

          return (deliver);

      }

      if (obj.ttl + obj.grace > 0s) {

          #// Object is in grace, deliver it

          #// Automatically triggers a background fetch

          return (deliver);

      }

      #// fetch & deliver once we get the result

      return (miss);

 }

 sub vcl_miss {

      return (fetch);

 }

 sub vcl_deliver {

     set resp.http.Via = "cache";

     unset resp.http.X-Varnish;

     set resp.http.Server="cache-server";

     unset resp.http.Age;

 #    set resp.http.x-hits = obj.hits;

     if (obj.hits > ) {

         set resp.http.X-Cache = "Hit aaaaaa CDN";

     }else {

         set resp.http.X-Cache = "Miss";

     }

     return (deliver);

 } 

 sub vcl_synth {

      set resp.http.Content-Type = "text/html; charset=utf-8";

      set resp.http.Retry-After = "";

      synthetic( {"<!DOCTYPE html>

  <html>

    <head>

      <title>"} + resp.status + " " + resp.reason + {"</title>

    </head>

    <body>

      <h1>Error "} + resp.status + " " + resp.reason + {"</h1>

      <p>"} + resp.reason + {"</p>

      <h3>Guru Meditation:</h3>

      <p>XID: "} + req.xid + {"</p>

      <hr>

      <p>Varnish cache server</p>

    </body>

  </html>

  "} );

      return (deliver);

 }

 sub vcl_backend_error {

      set beresp.http.Content-Type = "text/html; charset=utf-8";

      set beresp.http.Retry-After = "";

      synthetic( {"<!DOCTYPE html>

  <html>

    <head>

      <title>"} + beresp.status + " " + beresp.reason + {"</title>

    </head>

    <body>

      <h1>Error "} + beresp.status + " " + beresp.reason + {"</h1>

      <p>"} + beresp.reason + {"</p>

      <h3>Guru Meditation:</h3>

      <p>XID: "} + bereq.xid + {"</p>

      <hr>

      <p>Varnish cache server</p>

    </body>

  </html>

  "} );

      return (deliver);

 }

 sub vcl_fini {

      return (ok);

 }

 vcl 4.0;

 import std;

 import directors;

 backend fdfs_g1_s1 {

      .host = "192.168.20.151";

      .port = "";

      .probe = {

         .url = "/";

         .timeout   = 1s;

         .interval  = 10s;

         .window    = ;

         .threshold = ;

     }

 }

 backend fdfs_g1_s2 {

      .host = "192.168.20.152";

      .port = "";

      .probe = {

         .url = "/";

         .timeout   = 1s;

         .interval  = 10s;

         .window    = ;

         .threshold = ;

     }

 }

 backend fdfs_g2_s1 {

      .host = "192.168.20.113";

      .port = "";

      .probe = {

         .url = "/";

         .timeout   = 1s;

         .interval  = 10s;

         .window    = ;

         .threshold = ;

     }

 }

 backend fdfs_g2_s2 {

      .host = "192.168.20.115";

      .port = "";

      .probe = {

         .url = "/";

         .timeout   = 1s;

         .interval  = 10s;

         .window    = ;

         .threshold = ;

     }

 }

 acl purgers {

     "localhost";

     "127.0.0.1";

 }

 sub vcl_init {

     new g1vdir = directors.round_robin();

     g1vdir.add_backend(fdfs_g1_s1);

     g1vdir.add_backend(fdfs_g1_s2);

     new g2vdir = directors.round_robin();

     g2vdir.add_backend(fdfs_g2_s1);

     g2vdir.add_backend(fdfs_g2_s2);

    return (ok);

 }

 sub vcl_recv {

     if (req.url ~ "/group1") {

      set req.backend_hint = g1vdir.backend();

     }

     if (req.url ~ "/group2") {

      set req.backend_hint = g2vdir.backend();

     }

      if (req.http.x-forwarded-for) {

          set req.http.X-Forwarded-For = req.http.X-Forwarded-For + ", " + client.ip;

      } else {

          set req.http.X-Forwarded-For = client.ip;

      }    

      if (req.method == "PURGE") {    # PURGE请求的处理

         if (!client.ip ~ purgers) {

             return(synth(,"Method not allowed"));

         }

         #清理缓存

         return (purge);

      }

      # 禁止缓存的文件

      if (req.url ~ "\.(php|jsp|do|cgi)$") {

         return (pass);

      }

      if (req.method == "PRI") {

         #/* We do not support SPDY or HTTP/2.0 */

         return (synth());

      }

      if (req.method != "GET" &&

        req.method != "HEAD" &&

        req.method != "PUT" &&

        req.method != "POST" &&

        req.method != "TRACE" &&

        req.method != "OPTIONS" &&

        req.method != "DELETE") {

          #/* Non-RFC2616 or CONNECT which is weird. */

          return (pipe);

      }

      if (req.method != "GET" && req.method != "HEAD") {

          #/* We only deal with GET and HEAD by default */

          return (pass);

      }

      if (req.http.Authorization || req.http.Cookie) {

          #/* Not cacheable by default */

          return (pass);

      }

      return (hash);

 }

 sub vcl_backend_response {

     if (beresp.http.cache-control !~ "s-maxage") {

         if (bereq.url ~ "\.(gif|jpeg|jpg|png)$") {

         set beresp.ttl = 3600s;

         unset beresp.http.set-cookie;

         }    

         if (bereq.url ~ "\.(css|js)$") {

         set beresp.ttl = 600s;

         unset beresp.http.set-cookie;

         }    

         if (bereq.url ~ "^[^?]*\.(7z|avi|bz2|flac|flv|amr|gz|mka|mkv|mov|mp3|mp4|mpeg|mpg|ogg|ogm|opus|rar|tar|tgz|tbz|txz|wav|webm|xz|zip)(\?.*)?$") {

         unset beresp.http.set-cookie;

         set beresp.do_stream = true;

         set beresp.do_gzip = false;

         }

     } else {

         if (beresp.ttl > 0s) {

             unset beresp.http.Set-Cookie;

         }

    }

     if (beresp.ttl <= 0s || beresp.http.Set-Cookie || beresp.http.Surrogate-control ~ "no-store" || (!beresp.http.Surrogate-Control && beresp.http.Cache-Control ~ "no-cache|no-store|private") || beresp.http.Vary == "*") {

         set beresp.ttl = 120s;

         set beresp.uncacheable = true;

     }

     return (deliver);

 }

 sub vcl_backend_fetch {

     return (fetch);

 }

 sub vcl_pipe {

      # By default Connection: close is set on all piped requests, to stop

      # connection reuse from sending future requests directly to the

      # (potentially) wrong backend. If you do want this to happen, you can undo

      # it here.

      # unset bereq.http.connection;

      return (pipe);

 }

 sub vcl_pass {

      return (fetch);

 }

 sub vcl_hash {

      hash_data(req.url);

      if (req.http.host) {

          hash_data(req.http.host);

      } else {

          hash_data(server.ip);

      }

      return (lookup);

 }

 sub vcl_purge {

      return (synth(, "Purged"));

 }

 sub vcl_hit {

      if (obj.ttl >= 0s) {

          #// A pure unadultered hit, deliver it

          return (deliver);

      }

      if (obj.ttl + obj.grace > 0s) {

          #// Object is in grace, deliver it

          #// Automatically triggers a background fetch

          return (deliver);

      }

      #// fetch & deliver once we get the result

      return (miss);

 }

 sub vcl_miss {

      return (fetch);

 }

 sub vcl_deliver {

     set resp.http.Via = "cache";

     unset resp.http.X-Varnish;

     set resp.http.Server="cache-server";

     unset resp.http.Age;

 #    set resp.http.x-hits = obj.hits;

     if (obj.hits > ) {

         set resp.http.X-Cache = "Hit aaaaaa CDN";

     }else {

         set resp.http.X-Cache = "Miss";

     }

     return (deliver);

 } 

 sub vcl_synth {

      set resp.http.Content-Type = "text/html; charset=utf-8";

      set resp.http.Retry-After = "";

      synthetic( {"<!DOCTYPE html>

  <html>

    <head>

      <title>"} + resp.status + " " + resp.reason + {"</title>

    </head>

    <body>

      <h1>Error "} + resp.status + " " + resp.reason + {"</h1>

      <p>"} + resp.reason + {"</p>

      <h3>Guru Meditation:</h3>

      <p>XID: "} + req.xid + {"</p>

      <hr>

      <p>Varnish cache server</p>

    </body>

  </html>

  "} );

      return (deliver);

 }

 sub vcl_backend_error {

      set beresp.http.Content-Type = "text/html; charset=utf-8";

      set beresp.http.Retry-After = "";

      synthetic( {"<!DOCTYPE html>

  <html>

    <head>

      <title>"} + beresp.status + " " + beresp.reason + {"</title>

    </head>

    <body>

      <h1>Error "} + beresp.status + " " + beresp.reason + {"</h1>

      <p>"} + beresp.reason + {"</p>

      <h3>Guru Meditation:</h3>

      <p>XID: "} + bereq.xid + {"</p>

      <hr>

      <p>Varnish cache server</p>

    </body>

  </html>

  "} );

      return (deliver);

 }

 sub vcl_fini {

      return (ok);

 }