varnish and wordpress

[Miguel González]

Dear all,

  Probably since I´m a newbie I assume a cache system makes a "static"
copy of a web and serve it to the browser. I have several Wordpress
sites, same backend and speed load differs quite much (from 1 second to
6 seconds). Obviously size matters but shouldn´t load all items (CSS,
JS, images) almost at the same time? Webpagetest shows it´s not the case.

  I have tried to use together with Varnish other plugin caches as W3
Total Cache but the performance is even worse.

  Maybe my assumptions are wrong or my VCL is wrong.

  I have 4.1 as was suggested by someone from the list.

 Thanks!

 Miguel

my default.vcl:

#
# This is an example VCL file for Varnish.
#
# It does not do anything by default, delegating control to the
# builtin VCL. The builtin VCL is called when there is no explicit
# return statement.
#
# See the VCL chapters in the Users Guide at
https://www.varnish-cache.org/docs/
# and http://varnish-cache.org/trac/wiki/VCLExamples for more examples.

# Marker to tell the VCL compiler that this VCL has been adapted to the
# new 4.0 format.
vcl 4.0;

import std;

# Default backend definition. Set this to point to your content server.
backend default {
    .host = "127.0.0.1";
    .port = "82";
    .connect_timeout = 600s;
    .first_byte_timeout = 600s;
    .between_bytes_timeout = 600s;


}

acl purge {
        "localhost";
        "127.0.0.1";
}


# This function is used when a request is send by a HTTP client (Browser)
sub vcl_recv {

        # remove ?ver=xxxxx strings from urls so css and js files are
cached.
        # Watch out when upgrading WordPress, need to restart Varnish or
flush cache.
        set req.url = regsub(req.url, "\?ver=.*$", "");

        # Remove "replytocom" from requests to make caching better.
        set req.url = regsub(req.url, "\?replytocom=.*$", "");

        #We pass real IP and Port to the backend

        if (req.http.X-Forwarded-Proto == "https" ) {
           set req.http.X-Port = "443";
        } else {
           set req.http.X-Port = "80";
        }

        set req.http.X-Forwarded-For = regsub(req.http.X-Forwarded-For,
"^([^,]+),?.*$", "\1");


        # Normalize the header, remove the port (in case you're testing
this on various TCP ports)

        set req.http.Host = regsub(req.http.Host, ":[0-9]+", "");

        # Remove has_js and CloudFlare/Google Analytics __* cookies.
        set req.http.Cookie = regsuball(req.http.Cookie,
"(^|;\s*)(_[_a-z]+|has_js)=[^;]*", "");
        # Remove a ";" prefix, if present.
        set req.http.Cookie = regsub(req.http.Cookie, "^;\s*", "");


        # Allow purging from ACL
        if (req.method == "PURGE") {
                # If not allowed then a error 405 is returned
                if (!client.ip ~ purge) {
                        return(synth(405, "This IP is not allowed to
send PURGE requests."));
                }
                # If allowed, do a cache_lookup -> vlc_hit() or vlc_miss()
                return (purge);
        }

        # Post requests will not be cached
        #if (req.http.Authorization || req.method == "POST") {
        #       return (pass);
        #}

        # Pass anything other than GET and HEAD directly.
        if (req.method != "GET" && req.method != "HEAD") {
                return( pass );
        }      /* We only deal with GET and HEAD by default */


        #Woocommerce don't cache :
        if (req.url ~
"^/(cart|my-account/*|checkout|addons|logout|lost-password|product/*)") {
          return (pass);
        }

        #Woocommerce add to cart pass :
        if (req.url ~ "\?add-to-cart=" ) {
          return (pass);
        }
        if (req.url ~ "/wp-cron.php" || req.url ~ "preview=true") {
          return (pass);
        }

        # Woocommerce
        if (req.url ~ "(cart|my-account|checkout|addons)") {
          return (pass);
        }
        if ( req.url ~ "\?add-to-cart=" ) {
          return (pass);
        }


        # --- WordPress specific configuration
        # Did not cache the admin and login pages
        if (req.url ~
"nocache|cart|my-account|checkout|addons|tienda|mi-cuenta|carro|producto/*|login|wp-admin|wp-(comments-post|login|signup|activate|mail|cron)\.php|preview\=true|admin-ajax\.php|xmlrpc\.php|bb-admin|whm-server-status|server-status|control\.php|bb-login\.php|bb-reset-password\.php|register\.php")
{
            return (pass);
        }

        if (req.url ~ "(ajax|dynamic|custom)") {
             return(pass);
        }

        # Remove the "has_js" cookie
        set req.http.Cookie = regsuball(req.http.Cookie, "has_js=[^;]+(;
)?", "");

        # Remove any Google Analytics based cookies
        set req.http.Cookie = regsuball(req.http.Cookie, "__utm.=[^;]+(;
)?", "");

        # Remove the Quant Capital cookies (added by some plugin, all __qca)
        set req.http.Cookie = regsuball(req.http.Cookie, "__qc.=[^;]+(;
)?", "");

        # Remove the wp-settings-1 cookie
        set req.http.Cookie = regsuball(req.http.Cookie,
"wp-settings-1=[^;]+(; )?", "");

        # Remove the wp-settings-time-1 cookie
        set req.http.Cookie = regsuball(req.http.Cookie,
"wp-settings-time-1=[^;]+(; )?", "");

        # Remove the wp test cookie
        set req.http.Cookie = regsuball(req.http.Cookie,
"wordpress_test_cookie=[^;]+(; )?", "");

        # Are there cookies left with only spaces or that are empty?
        if (req.http.cookie ~ "^ *$") {
                    unset req.http.cookie;
        }

        # Cache the following files extensions
        if (req.url ~ "\.(txt|css|js|png|gif|jp(e)?g|swf|ico)") {
                unset req.http.cookie;
        }

        # Normalize Accept-Encoding header and compression
        # https://www.varnish-cache.org/docs/3.0/tutorial/vary.html
        if (req.http.Accept-Encoding) {
                # Do no compress compressed files...
                if (req.url ~ "\.(jpg|png|gif|gz|tgz|bz2|tbz|mp3|ogg)$") {
                                unset req.http.Accept-Encoding;
                } elsif (req.http.Accept-Encoding ~ "gzip") {
                        set req.http.Accept-Encoding = "gzip";
                } elsif (req.http.Accept-Encoding ~ "deflate") {
                        set req.http.Accept-Encoding = "deflate";
                } else {
                        unset req.http.Accept-Encoding;
                }
        }

        # Check the cookies for wordpress-specific items
        if (req.http.Cookie ~ "wordpress_" || req.http.Cookie ~
"comment_") {
                return (pass);
        }
        if (!req.http.cookie) {
                unset req.http.cookie;
        }

        # --- End of WordPress specific configuration

        # Did not cache HTTP authentication and HTTP Cookie
        if (req.http.Authorization || req.http.Cookie) {
                # Not cacheable by default
                return (pass);
        }

        # Cache all others requests
        return (hash);
}

sub vcl_pipe {
        return (pipe);
}

sub vcl_pass {
        return (fetch);
}

# The data on which the hashing will take place
sub vcl_hash {
        hash_data(req.url);
        if (req.http.host) {
        hash_data(req.http.host);
        } else {
        hash_data(server.ip);
        }

        # If the client supports compression, keep that in a different cache
        if (req.http.Accept-Encoding) {
                hash_data(req.http.Accept-Encoding);
        }

        return (lookup);
}

# This function is used when a request is sent by our backend (Nginx server)
sub vcl_backend_response {
        # Remove some headers we never want to see
        unset beresp.http.Server;
        unset beresp.http.X-Powered-By;

        if (beresp.http.content-type ~
"(text|javascript|application/x-font-woff)") {
          set beresp.do_gzip = true;
        }

        # For static content strip all backend cookies
        if (bereq.url ~ "\.(css|js|png|gif|jp(e?)g)|swf|ico") {
                unset beresp.http.cookie;
        }
        # Don't store backend
        if (bereq.url ~ "wp-(login|admin)" || bereq.url ~ "preview=true") {
                set beresp.uncacheable = true;
                set beresp.ttl = 30s;
                return (deliver);
        }

        # Only allow cookies to be set if we're in admin area
                if (!(bereq.url ~
"(wp-login|cart|my-account|checkout|addons|tienda|mi-cuenta|carro|producto/*|login|wp-admin|preview=true)"))
{
                unset beresp.http.set-cookie;
        }

        # don't cache response to posted requests or those with basic auth
        if ( bereq.method == "POST" || bereq.http.Authorization ) {
                set beresp.uncacheable = true;
                set beresp.ttl = 120s;
                return (deliver);
        }

        # don't cache search results
        if ( bereq.url ~ "\?s=" ){
                set beresp.uncacheable = true;
                set beresp.ttl = 120s;
                return (deliver);
        }

        # only cache status ok
        if ( beresp.status != 200 ) {
                set beresp.uncacheable = true;
                set beresp.ttl = 120s;
                return (deliver);
        }

        # A TTL of 24h
        set beresp.ttl = 24h;
        # Define the default grace period to serve cached content
        #set beresp.grace = 30s;
        set beresp.grace = 1h;

        return (deliver);
}

# The routine when we deliver the HTTP request to the user
# Last chance to modify headers that are sent to the client
sub vcl_deliver {
        if (obj.hits > 0) {
                set resp.http.X-Cache = "cached";
        } else {
                set resp.http.x-Cache = "uncached";
        }

        # Remove some headers: PHP version
        unset resp.http.X-Powered-By;

        # Remove some headers: Apache version & OS
        unset resp.http.Server;

        # Remove some heanders: Varnish
        unset resp.http.Via;
        unset resp.http.X-Varnish;

        return (deliver);
}

sub vcl_init {
        return (ok);
}

sub vcl_fini {
        return (ok);
}