Wordpress Varnish VCL File

default.vcl

vcl 4.0;

import std;
import directors;

backend server1 {
    .host = "127.0.0.1";             # IP or Hostname of backend
    .port = "8080";                  # Port Apache or whatever is listening
    .max_connections = 800;          # That's it
    .first_byte_timeout = 300s;      # How long to wait before we receive a first byte from our backend?
    .connect_timeout = 300s;         # How long to wait for a backend connection?
    .between_bytes_timeout = 300s;   # How long to wait between bytes received from our backend?
}

# Only allow purging from specific IPs
acl purge {
    "localhost";
    "127.0.0.1";
}

# Called when VCL is loaded, before any requests pass through it. Typically used to initialize VMODs.
sub vcl_init {
    new vdir = directors.round_robin();
    vdir.add_backend(server1);
    #vdir.add_backend(server2);
    #vdir.add_backend(server3);
}

# Called at the beginning of a request, after the complete request has been received and parsed.
# Its purpose is to decide whether or not to serve the request, how to do it, and, if applicable,
# which backend to use.
# also used to modify the request
sub vcl_recv {

    # send all traffic to the vdir director
    set req.backend_hint = vdir.backend();

    # TURN OFF CACHE when needed (just uncomment this only when needed)
    # return(pass);

    # Allow purging from ACL
    if (req.method == "PURGE") {
        if (!client.ip ~ purge) {
            return(synth(405,"Not allowed."));
        }
        return (purge);
    }

    # 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]+", "");

    # set or append the client.ip to X-Forwarded-For header. Important for logging and correct IPs.
    if (req.restarts == 0) {
        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;
        }
    }

    ###
    ### Do not Cache: special cases
    ###

    # Do not cache AJAX requests.
    if (req.http.X-Requested-With == "XMLHttpRequest") {
        return(pass);
    }

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

    # Only cache GET or HEAD requests. This makes sure the POST requests are always passed.
    #if (req.method != "GET" && req.method != "HEAD") {
    #  return (pass);
    #}

    # Dont Cache WordPress post pages and edit pages
    if (req.url ~ "(wp-admin|post\.php|edit\.php|wp-login)") {
        return(pass);
    }
    if (req.url ~ "/wp-cron.php" || req.url ~ "preview=true") {
        return (pass);
    }

    # WordPress Social Login Plugin. Note: Need to develop this. Please share if you have an example.
    if (req.url ~ "(wordpress-social-login|wp-social-login)") {
        return (pass);
    }

    # WP-Affiliate
    if ( req.url ~ "\?ref=" ) {
        return (pass);
    }

    # Similarly add for other plugis in required

    ###
    ###    http header Cookie
    ###    Remove some cookies (if found)
    ###    Cache This Stuff
    ###
    # https://varnish-cache.org/docs/4.1/users-guide/increasing-your-hitrate.html#cookies

    ### COOKIE MADNESS.

    # 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.=[^;]+(; )?", "");
    set req.http.Cookie = regsuball(req.http.Cookie, "_ga=[^;]+(; )?", "");
    set req.http.Cookie = regsuball(req.http.Cookie, "utmctr=[^;]+(; )?", "");
    set req.http.Cookie = regsuball(req.http.Cookie, "utmcmd.=[^;]+(; )?", "");
    set req.http.Cookie = regsuball(req.http.Cookie, "utmccn.=[^;]+(; )?", "");

    # 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=[^;]+(; )?", "");

    # Remove the phpBB cookie. This will help us cache bots and anonymous users.
    set req.http.Cookie = regsuball(req.http.Cookie, "style_cookie=[^;]+(; )?", "");
    set req.http.Cookie = regsuball(req.http.Cookie, "phpbb3_psyfx_track=[^;]+(; )?", "");

    # Remove the cloudflare cookie
    ##set req.http.Cookie = regsuball(req.http.Cookie, "__cfduid=[^;]+(; )?", "");
    # Remove has_js and Cloudflare/Google Analytics __* cookies.
    # Taken from cloudflare https://support.cloudflare.com/hc/en-us/articles/200169376-Can-I-use-Cloudflare-and-Varnish-together-
    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*", "");

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

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

    # Just for testing
    #std.syslog(0, req.http.Cookie);

    # MEGA DROP. Drop ALL cookies sent to WordPress, except those originating from the URLs defined.
    # This increases HITs significantly, but be careful it can also break plugins that need cookies.
    # Note: The /members/ directory had problems with PMP login and social login plugin.
    # Adding it to the exclude list here (and including it below in the "Retain cookies" list) fixed login.
    # This works better than than other cookie removal examples found on varnish's website.
    # Note phpBB directory (forumPM) also passes cookies here.
    if (!(req.url ~ "(wp-login|wp-admin|cart|my-account|checkout|addons|wordpress-social-login|wp-login\.php|forumPM|members)")) {
        unset req.http.cookie;
    }

    # Normalize the query arguments.
    # Note: Placing this above the "do not cache" section breaks some WP theme elements and admin functionality.
    set req.url = std.querysort(req.url);

    # Large static files are delivered directly to the end-user without
    # waiting for Varnish to fully read the file first.
    # Varnish 4 fully supports Streaming, so see do_stream in vcl_backend_response() to witness the glory.
    if (req.url ~ "^[^?]*\.(mp[34]|rar|tar|tgz|wav|zip|bz2|xz|7z|avi|mov|ogm|mpe?g|mk[av])(\?.*)?$") {
        unset req.http.Cookie;
        return (hash);
    }

    # Cache all static files by Removing all cookies for static files
    # Remember, do you really need to cache static files that don't cause load? Only if you have memory left.
    # Here I decide to cache these static files. For me, most of them are handled by the CDN anyway.
    if (req.url ~ "^[^?]*\.(bmp|bz2|css|doc|eot|flv|gif|ico|jpeg|jpg|js|less|pdf|png|rtf|swf|txt|woff|xml)(\?.*)?$") {
        unset req.http.Cookie;
        return (hash);
    }

    # Cache all static files by Removing all cookies for static files - These file extensions are generated by WP Super Cache.
    if (req.url ~ "^[^?]*\.(html|htm|gz)(\?.*)?$") {
        unset req.http.Cookie;
        return (hash);
    }

    # Similarly handle for W3TC, WP Rocket or other caching plugins?


    # Do not cache Authorized requests.
    #  if (req.http.Authorization) {
    #      return(pass);
    #  }

    # Cache all others requests.
    # Note Varnish v4: vcl_recv must now return hash instead of lookup
    return (hash);
}

# Called upon entering pipe mode.
# In this mode, the request is passed on to the backend, and any further data from both the client
# and backend is passed on unaltered until either end closes the connection. Basically, Varnish will
# degrade into a simple TCP proxy, shuffling bytes back and forth. For a connection in pipe mode,
# no other VCL subroutine will ever get called after vcl_pipe.
sub vcl_pipe {
    # Note that only the first request to the backend will have
    # X-Forwarded-For set.  If you use X-Forwarded-For and want to
    # have it set for all requests, make sure to have:
    # set bereq.http.connection = "close";
    # here.  It is not set by default as it might break some broken web
    # applications, like IIS with NTLM authentication.

    # set bereq.http.Connection = "Close";

    return (pipe);
}


# Called upon entering pass mode. In this mode, the request is passed on to the backend, and the
# backend's response is passed on to the client, but is not entered into the cache. Subsequent
# requests submitted over the same client connection are handled normally.
sub vcl_pass {
    # return (pass);
}

# Called after vcl_recv to create a hash value for the request. This is used as a key
# to look up the object in Varnish.
# 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);
    }

    # hash cookies for requests that have them
    if (req.http.Cookie) {
        hash_data(req.http.Cookie);
    }

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

    return (lookup);
}


# Called after the response headers has been successfully retrieved from the backend.
# Handle the HTTP request coming from our backend
sub vcl_backend_response {
    # Sometimes, a 301 or 302 redirect formed via Apache's mod_rewrite can mess with the HTTP port that is being passed along.
    # This often happens with simple rewrite rules in a scenario where Varnish runs on :80 and Apache on :8080 on the same box.
    # A redirect can then often redirect the end-user to a URL on :8080, where it should be :80.
    # This may need fine tuning on your setup.
    # To prevent accidental replace, we only filter the 301/302 redirects for now.
    if (beresp.status == 301 || beresp.status == 302) {
        set beresp.http.Location = regsub(beresp.http.Location, ":[0-9]+", "");
    }

    ###
    ### Overall TTL
    ### Note: The TTL is designed to be somewhat aggressive here, to keep things in cache.
    ###

    # Lets get this party started.
    # This will keep things in cache longer
    if (beresp.ttl > 0s) {
        unset beresp.http.expires;
        set beresp.http.cache-control = "max-age=900";
        set beresp.ttl = 4d; # how long you cache objects
        set beresp.http.magicmarker = "1";
    }

    # Allow stale content, in case the backend goes down.
    # make Varnish keep all objects for x hours beyond their TTL
    set beresp.grace = 12h;

    ###
    ### Static Files
    ###

    # Enable cache for all static files
    # Monitor your cache size, if you get data nuked out of it, consider giving up the static file cache.
    # More reading here: https://ma.ttias.be/stop-caching-static-files/
    if (bereq.url ~ "^[^?]*\.(bmp|bz2|css|doc|eot|flv|gif|ico|jpeg|jpg|js|less|mp[34]|pdf|png|rar|rtf|swf|tar|tgz|txt|wav|woff|xml|zip)(\?.*)?$") {
        set beresp.ttl = 2d; # set a TTL for these optional.
        unset beresp.http.set-cookie;
    }

    # Cache all static files by Removing all cookies for static files - Note: These file extensions are generated by WordPress WP Super Cache.
    if (bereq.url ~ "^[^?]*\.(html|htm|gz)(\?.*)?$") {
        set beresp.ttl = 1d; # set a TTL for these optional.
        unset beresp.http.set-cookie;
    }

    # Similarly handle for W3TC, WP Rocket or other caching plugins?


    ###
    ### Targeted TTL
    ###

    # Long ttl sites
    if (bereq.url ~ "(example.com|example2.com)") {
        set beresp.ttl = 1w;
    }

    # Unset Cookies except for WordPress admin and WooCommerce pages
    if ( (!(bereq.url ~ "(wp-(login|admin)|login|cart|my-account/*|checkout|addons|logout|lost-password|product/*)")) ) {
      unset beresp.http.set-cookie;
    }

    # Large static files are delivered directly to the end-user without
    # waiting for Varnish to fully read the file first.
    # Varnish 4 fully supports Streaming, so use streaming here to avoid locking.
    # I do not stream large files from my server, I use a CDN or dropbox, so I have not tested this.
    if (bereq.url ~ "^[^?]*\.(mp[34]|rar|tar|tgz|wav|zip|bz2|xz|7z|avi|mov|ogm|mpe?g|mk[av])(\?.*)?$") {
        unset beresp.http.set-cookie;
        set beresp.do_stream = true;  # Check memory usage it'll grow in fetch_chunksize blocks (128k by default) if the backend doesn't send a Content-Length header, so only enable it for big objects
        set beresp.do_gzip = false;   # Don't try to compress it for storage
    }

    # 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);
    }

    return (deliver);
}


# The routine when we deliver the HTTP request to the user
# Last chance to modify headers that are sent to the client
# Called before a cached object is delivered to the client.
sub vcl_deliver {

    if (obj.hits > 0) { # Add debug header to see if it's a HIT/MISS and the number of hits, disable when not needed
        set resp.http.X-Cache = "HIT";
    } else {
        set resp.http.X-Cache = "MISS";
    }

    # Please note that obj.hits behaviour changed in 4.0, now it counts per objecthead, not per object
    # and obj.hits may not be reset in some cases where bans are in use. See bug 1492 for details.
    # So take hits with a grain of salt
    set resp.http.X-Cache-Hits = obj.hits;

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

    # Remove some headers: Apache version & OS
    unset resp.http.Server;
    unset resp.http.X-Varnish;
    unset resp.http.Age;
    unset resp.http.Via;
    unset resp.http.Link;
    unset resp.http.X-Generator;

    if (resp.http.magicmarker) {
        unset resp.http.magicmarker;
        set resp.http.age = "0";
    }

    return (deliver);
}

# Used to generate content within Varnish
# Error messages can be created here
# Other use cases: redirecting users (301/302 redirects)
sub vcl_synth {
    if (resp.status == 720) {
        # We use this special error status 720 to force redirects with 301 (permanent) redirects
        # To use this, call the following from anywhere in vcl_recv: return (synth(720, "http://host/new.html"));
        set resp.http.Location = resp.reason;
        set resp.status = 301;
        return (deliver);
    } elseif (resp.status == 721) {
        # And we use error status 721 to force redirects with a 302 (temporary) redirect
        # To use this, call the following from anywhere in vcl_recv: return (synth(720, "http://host/new.html"));
        set resp.http.Location = resp.reason;
        set resp.status = 302;
        return (deliver);
    }

    return (deliver);
}

# Called when VCL is discarded only after all requests have exited the VCL.
# Typically used to clean up VMODs.
sub vcl_fini {
    return (ok);
}