Varnish 5.x support
Varnish 5.x support

file:a/readme.txt -> file:b/readme.txt
--- a/readme.txt
+++ b/readme.txt
@@ -3,14 +3,14 @@
 Contributors: razvanstanga
 Tags: varnish, purge, cache, caching, optimization, performance, traffic
 Requires at least: 4.0
-Tested up to: 4.7
-Stable tag: 1.5.5
+Tested up to: 4.8
+Stable tag: 1.6
 License: GPLv2 or later
 
-Wordpress Varnish Cache 3.x/4.x integration
+Wordpress Varnish Cache 3.x/4.x/5.x integration
 
 == Description ==
-Complete Wordpress Varnish Cache 3.x/4.x integration.
+Complete Wordpress Varnish Cache 3.x/4.x/5.x integration.
 
 This plugin handles all integration with Varnish Cache. It was designed for high traffic websites.
 
@@ -116,6 +116,9 @@
 
 == Changelog ==
 
+= 1.6 =
+* Varnish 5.x support
+
 = 1.5.5 =
 * fixed ob_end_flush error in wp-admin while debug is on. thanks @samlangdon
 

--- /dev/null
+++ b/varnish-conf/v5/LICENSE
@@ -1,1 +1,340 @@
-
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+
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+Public License instead of this License.
+

--- /dev/null
+++ b/varnish-conf/v5/README.rst
@@ -1,1 +1,149 @@
+======================
+varnish-vcl-collection
+======================
 
+Collection of Varnish VCL files.  The purpose of this collection is to make
+it easier to configure varnish for some common setups and behaviors.  Some
+of these files require you to define specific ACLs in your main VCL, and also
+note that the order of including files could change the behavior of Varnish.
+
+The main goal for this VCL Collection is to provide a simple config with just
+a few options that can make Varnish work for the majority of sites. Most of
+the "configuration" is done by choosing which files to include and defining
+ACLs. We hope to provide a robust configuration that can be used with
+relatively little information or control over what is actually running on
+the backend.  This is particularly useful for managed web hosts who want
+to have customers benefit from the performance of a caching proxy without
+limiting what can run on the web backend and without customizing the
+configuration for each customer.
+
+See `default.vcl` for an example of how to use this collection
+of VCLs to configure Varnish for a WordPress site.
+
+
+CloudFlare
+==========
+
+If you use CloudFlare and the backend is running `mod_cloudflare` (for Apache)
+or `http_realip_module` (for Nginx), then you should use `lib/cloudflare.vcl`.
+
+CloudFlare uses the HTTP Header `CF-Connecting-IP` to store the original
+client IP address.  Note that unlike the `X-Forwarded-For` Header, this just
+contains the original IP address, not the entire forward chain.
+
+If you are using a CloudFlare Railgun server, or have any other trusted proxy
+servers between Varnish and CloudFlare, you will need to specify them in the
+`cloudflare` ACL.
+
+Also note that you will need to make sure that Varnish's IP is configured
+as trusted in `mod_cloudflare` or the `http_realip_module` on the backend.
+
+Example usage::
+
+	include "lib/cloudflare.vcl";
+
+	acl cloudflare {
+		# put the IP of your Railgun (or proxy) server here
+		# "1.2.3.4";
+	}
+
+
+Mobile Device Optimizaiton
+==========================
+
+Different applications optimize for mobile devices in different ways.  The
+best way is to use an "adaptive" design so that the same HTML is served to
+both desktop and mobile devices.  If your application is "adaptive", then
+no special Varnish config is necessary; all devices will access the same
+objects in the Varnish cache.
+
+However, if your application does serve different content to different
+devices, then you'll need to handle that in Varnish.  Since applications
+do mobile device detection differently, the VCL code included here is
+intentionally limited and simple.  Crafting a custom configuration to handle
+the way your application treats mobile devices will usually give better
+results than using one of the following standard configs.
+
+`lib/mobile_cache.vcl` simply adds the string `mobile` to the hash data to
+give mobile devices a separate cache from non-mobile devices.  This is only
+viable if your application serves just 2 different versions of each page
+depending on if the visitor is on a mobile device or not (and if the
+application uses the same method to detect mobile devices).  Any disagreement
+between `mobile_cache.vcl` and your backend on what User-Agents should be
+considered "mobile" could mean that the incorrect versions of pages are
+served to some visitors.
+
+`lib/mobile_pass.vcl` simply disables caching for mobile devices.  This is
+not good for performance, but will at least will prevent serving the
+incorrect version of pages to mobile visitors.
+
+
+HTTP Purging
+============
+
+Include `lib/purge.vcl` to allow purging pages from the cache using the HTTP
+PURGE method.  This uses the ban feature of varnish and will make bans take
+advantage of Varnish's ban-lurker.  You will need to specify a `purge` ACL
+so that only requests coming from your application are allowed to purge.
+
+Example usage::
+
+	include "lib/purge.vcl";
+
+	acl purge {
+		# include the IP of your app if it isn't on localhost
+		"localhost";
+		"127.0.0.1";
+	}
+
+There are several different possible behaviors of HTTP purging which can be
+controlled with the X-VC-Purge-Method HTTP header.  This config will be smart
+and attempt to automatically pick the best method based on the URL if you
+don't use an X-VC-Purge-Method header.  See the comments in `lib/purge.vcl` for
+details.
+You can also use the X-VC-Purge-Key method. Generate a MD5/SHA-256 hash and fill it on line
+if (req.http.X-VC-Purge-Key == "hash-to-be-filled-in") {
+in lib/purge.vcl. Then use the same hash in Varnish Caching WP admin.
+
+
+Static File Caching
+===================
+
+Include `lib/static.vcl` to use a simple set of rules to cache static files.
+This will ignore the query string part of request URLs, and discard all
+cookies for these requests.  This will also cache static files for 24 hours.
+
+The cache behavior for this vcl can be bypassed by adding `nocache` to the
+url.  For example, `http://example.com/foo.jpg?nocache` will always
+retrieve the file from the backend instead of serving from the cache.
+
+
+Big Files
+=========
+
+Varnish cannot cache files larger than the entire cache.  Additionally, a few
+large files could potentially fill up the cache and force many more small
+files to be removed from the cache. Use `lib/bigfiles.vcl` or
+`lib/bigfiles_pipe.vcl` to prevent caching files larger than 10 MB.  This
+size was chosen because this should allow most common website assets to be
+cached.  Files larger than 10 MB such as videos, long podcasts, or binary
+downloads are better suited to be served with a CDN or some server separate
+from your main web application.  This config will still allow Varnish to
+serve these large files, but the files will always be retrieved from the
+backend.
+
+`lib/bigfiles.vcl` marks files with `hit_for_pass` when they are above the
+size threshold.  However this only works in Varnish 3.0.3 or later.  Earlier
+versions of Varnish will instead show an internal server error when this
+method is used.  In the case of these older versions of Varnish, you should
+use `lib/bigfiles_pipe.vcl`, which instead pipes the request.
+
+Your main VCL must have `import std;`.  This import line is not included
+within the files themselves because having an import multiple times in a
+Varnish config (counting all included files) produces a compile error.
+
+Example usage::
+
+	import std;
+	include "lib/bigfiles.vcl";
+

--- /dev/null
+++ b/varnish-conf/v5/conf/acl.vcl
@@ -1,1 +1,10 @@
+acl cloudflare {
+    # set this ip to your Railgun IP (if applicable)
+    # "1.2.3.4";
+}
 
+acl purge {
+    "localhost";
+    "127.0.0.1";
+    #"192.168.0.2";
+}

--- /dev/null
+++ b/varnish-conf/v5/conf/backend.vcl
@@ -1,1 +1,16 @@
+import directors;
 
+backend backend1 {
+    .host = "192.168.0.2";
+    .port = "80";
+}
+
+sub vcl_init {
+    new backends = directors.round_robin();
+    backends.add_backend(backend1);
+}
+
+sub vcl_recv {
+    set req.backend_hint = backends.backend();
+}
+

--- /dev/null
+++ b/varnish-conf/v5/default.vcl
@@ -1,1 +1,218 @@
-
+vcl 4.0;
+
+include "conf/backend.vcl";
+include "conf/acl.vcl";
+
+import std;
+
+include "lib/xforward.vcl";
+include "lib/cloudflare.vcl";
+include "lib/purge.vcl";
+include "lib/bigfiles.vcl";
+include "lib/static.vcl";
+
+# Pick just one of the following:
+# (or don't use either of these if your application is "adaptive")
+# include "lib/mobile_cache.vcl";
+# include "lib/mobile_pass.vcl";
+
+### WordPress-specific config ###
+sub vcl_recv {
+    # pipe on weird http methods
+    if (req.method !~ "^GET|HEAD|PUT|POST|TRACE|OPTIONS|DELETE$") {
+        return(pipe);
+    }
+
+    # Implementing websocket support (https://www.varnish-cache.org/docs/4.0/users-guide/vcl-example-websockets.html)
+    if (req.http.Upgrade ~ "(?i)websocket") {
+        return (pipe);
+    }
+
+    # redirect yourdomain.com to www.yourdomain.com
+    #if (req.http.host ~ "^yourdomain\.com$") {
+    #    set req.http.X-VC-Redirect = "http://www.yourdomain.com" + req.url;
+    #    return (synth(750, "Moved permanently"));
+    #}
+
+    # if you use a subdomain for admin section, do not cache it
+    #if (req.http.host ~ "admin.yourdomain.com") {
+    #    set req.http.X-VC-Cacheable = "NO:Admin domain";
+    #    return(pass);
+    #}
+
+    ### Check for reasons to bypass the cache!
+    # never cache anything except GET/HEAD
+    if (req.method != "GET" && req.method != "HEAD") {
+        set req.http.X-VC-Cacheable = "NO:Request method:" + req.method;
+        return(pass);
+    }
+
+    # don't cache logged-in users. you can set users `logged in cookie` name in settings
+    if (req.http.Cookie ~ "flxn34napje9kwbwr4bjwz5miiv9dhgj87dct4ep0x3arr7ldif73ovpxcgm88vs") {
+        set req.http.X-VC-Cacheable = "NO:Found logged in cookie";
+        return(pass);
+    }
+
+    # don't cache ajax requests
+    if (req.http.X-Requested-With == "XMLHttpRequest") {
+        set req.http.X-VC-Cacheable = "NO:Requested with: XMLHttpRequest";
+        return(pass);
+    }
+
+    # don't cache these special pages. Not needed, left here as example
+    #if (req.url ~ "nocache|wp-admin|wp-(comments-post|login|activate|mail)\.php|bb-admin|server-status|control\.php|bb-login\.php|bb-reset-password\.php|register\.php") {
+    #    set req.http.X-VC-Cacheable = "NO:Special page: " + req.url;
+    #    return(pass);
+    #}
+
+    ### looks like we might actually cache it!
+    # fix up the request
+    set req.url = regsub(req.url, "\?replytocom=.*$", "");
+
+    # strip query parameters from all urls (so they cache as a single object)
+    # be carefull using this option
+    #if (req.url ~ "\?.*") {
+    #    set req.url = regsub(req.url, "\?.*", "");
+    #}
+
+    # Remove has_js, Google Analytics __*, and wooTracker cookies.
+    set req.http.Cookie = regsuball(req.http.Cookie, "(^|;\s*)(has_js|wooTracker)=[^;]*", "");
+    set req.http.Cookie = regsuball(req.http.Cookie, "__utm.=[^;]+(; )?", "");
+    set req.http.Cookie = regsuball(req.http.Cookie, "_ga=[^;]+(; )?", "");
+    set req.http.Cookie = regsuball(req.http.Cookie, "_gat=[^;]+(; )?", "");
+    set req.http.Cookie = regsuball(req.http.Cookie, "utmctr=[^;]+(; )?", "");
+    set req.http.Cookie = regsuball(req.http.Cookie, "utmcmd.=[^;]+(; )?", "");
+    set req.http.Cookie = regsuball(req.http.Cookie, "utmccn.=[^;]+(; )?", "");
+    set req.http.Cookie = regsub(req.http.Cookie, "^;\s*", "");
+    # Remove DoubleClick offensive cookies
+    set req.http.Cookie = regsuball(req.http.Cookie, "__gads=[^;]+(; )?", "");
+
+    # Remove the Quant Capital cookies (added by some plugin, all __qca)
+    set req.http.Cookie = regsuball(req.http.Cookie, "__qc.=[^;]+(; )?", "");
+
+    # Remove the AddThis cookies
+    set req.http.Cookie = regsuball(req.http.Cookie, "__atuv.=[^;]+(; )?", "");
+
+    # Remove a ";" prefix in the cookie if present
+    set req.http.Cookie = regsuball(req.http.Cookie, "^;\s*", "");
+
+    # Are there cookies left with only spaces or that are empty?
+    if (req.http.Cookie ~ "^\s*$") {
+        unset req.http.Cookie;
+    }
+
+    # Protecting against the HTTPOXY CGI vulnerability.
+    unset req.http.proxy;
+
+    # Remove the Google Analytics added parameters.
+    if (req.url ~ "(\?|&)(utm_source|utm_medium|utm_campaign|utm_content|gclid|cx|ie|cof|siteurl)=") {
+        set req.url = regsuball(req.url, "&(utm_source|utm_medium|utm_campaign|utm_content|gclid|cx|ie|cof|siteurl)=([A-z0-9_\-\.%25]+)", "");
+        set req.url = regsuball(req.url, "\?(utm_source|utm_medium|utm_campaign|utm_content|gclid|cx|ie|cof|siteurl)=([A-z0-9_\-\.%25]+)", "?");
+        set req.url = regsub(req.url, "\?&", "?");
+        set req.url = regsub(req.url, "\?$", "");
+    }
+
+    # Strip hash, server doesn't need it.
+    if (req.url ~ "\#") {
+        set req.url = regsub(req.url, "\#.*$", "");
+    }
+
+    # Strip a trailing ? if it exists
+    if (req.url ~ "\?$") {
+        set req.url = regsub(req.url, "\?$", "");
+    }
+
+    # Normalize the query arguments
+    set req.url = std.querysort(req.url);
+
+    return(hash);
+}
+
+sub vcl_hash {
+    set req.http.hash = req.url;
+    if (req.http.host) {
+        set req.http.hash = req.http.hash + "#" + req.http.host;
+    } else {
+        set req.http.hash = req.http.hash + "#" + server.ip;
+    }
+    # Add the browser cookie only if cookie found. Not needed, left here as example
+    #if (req.http.Cookie ~ "wp-postpass_|wordpress_logged_in_|comment_author|PHPSESSID") {
+    #    hash_data(req.http.Cookie);
+    #    set req.http.hash = req.http.hash + "#" + req.http.Cookie;
+    #}
+}
+
+sub vcl_backend_response {
+    # make sure grace is at least 2 minutes
+    if (beresp.grace < 2m) {
+        set beresp.grace = 2m;
+    }
+
+    # overwrite ttl with X-VC-TTL
+    if (beresp.http.X-VC-TTL) {
+        set beresp.ttl = std.duration(beresp.http.X-VC-TTL + "s", 0s);
+    }
+
+    # catch obvious reasons we can't cache
+    if (beresp.http.Set-Cookie) {
+        set beresp.ttl = 0s;
+    }
+
+    # Don't cache object as instructed by header bereq.X-VC-Cacheable
+    if (bereq.http.X-VC-Cacheable ~ "^NO") {
+        set beresp.http.X-VC-Cacheable = bereq.http.X-VC-Cacheable;
+        set beresp.uncacheable = true;
+        set beresp.ttl = 120s;
+
+    # Varnish determined the object is not cacheable
+    } else if (beresp.ttl <= 0s) {
+        if (!beresp.http.X-VC-Cacheable) {
+            set beresp.http.X-VC-Cacheable = "NO:Not cacheable, ttl: "+ beresp.ttl;
+        }
+        set beresp.uncacheable = true;
+        set beresp.ttl = 120s;
+
+    # You are respecting the Cache-Control=private header from the backend
+    } else if (beresp.http.Cache-Control ~ "private") {
+        set beresp.http.X-VC-Cacheable = "NO:Cache-Control=private";
+        set beresp.uncacheable = true;
+        set beresp.ttl = 120s;
+
+    # Cache object
+    } else if (beresp.http.X-VC-Enabled ~ "true") {
+        if (!beresp.http.X-VC-Cacheable) {
+            set beresp.http.X-VC-Cacheable = "YES:Is cacheable, ttl: " + beresp.ttl;
+        }
+
+    # Do not cache object
+    } else if (beresp.http.X-VC-Enabled ~ "false") {
+        if (!beresp.http.X-VC-Cacheable) {
+            set beresp.http.X-VC-Cacheable = "NO:Disabled";
+        }
+        set beresp.ttl = 0s;
+    }
+
+    # Avoid caching error responses
+    if (beresp.status == 404 || beresp.status >= 500) {
+        set beresp.ttl   = 0s;
+        set beresp.grace = 15s;
+    }
+
+    # Deliver the content
+    return(deliver);
+}
+
+sub vcl_synth {
+    if (resp.status == 750) {
+        set resp.http.Location = req.http.X-VC-Redirect;
+        set resp.status = 302;
+        return(deliver);
+    }
+}
+
+sub vcl_pipe {
+     if (req.http.upgrade) {
+         set bereq.http.upgrade = req.http.upgrade;
+     }
+}
+

--- /dev/null
+++ b/varnish-conf/v5/lib/bigfiles.vcl
@@ -1,1 +1,11 @@
+# bigfiles.vcl -- Bypass Cache for Large Files
 
+sub vcl_backend_response {
+    # Bypass cache for files > 10 MB
+    if (std.integer(beresp.http.Content-Length, 0) > 10485760) {
+        set beresp.uncacheable = true;
+        set beresp.ttl = 120s;
+        return (deliver);
+    }
+}
+

--- /dev/null
+++ b/varnish-conf/v5/lib/bigfiles_pipe.vcl
@@ -1,1 +1,23 @@
+# bigfiles_pipe.vcl -- Pipe for Large Files
 
+# You must have "import std;" in your main vcl:
+# import std;
+
+# NOTE: Using restart and pipe is a workaround for a bug in varnish prior to
+# 3.0.3.  In 3.0.3+, hit_for_pass in vcl_fetch is all that is necessary.
+
+sub vcl_recv {
+    if (req.http.X-Pipe-Big-File && req.restarts > 0) {
+        unset req.http.X-Pipe-Big-File;
+        return (pipe);
+    }
+}
+
+sub vcl_fetch {
+    # Bypass cache for files > 10 MB
+    if (std.integer(beresp.http.Content-Length, 0) > 10485760) {
+        set req.http.X-Pipe-Big-File = "Yes";
+        return (restart);
+    }
+}
+

--- /dev/null
+++ b/varnish-conf/v5/lib/cloudflare.vcl
@@ -1,1 +1,41 @@
+# cloudflare.vcl -- CloudFlare HTTP Headers
 
+# This should generally be loaded first to make sure that the headers
+# get set appropriately for all requests.
+
+acl official_cloudflare {
+    # https://www.cloudflare.com/ips-v4
+    "204.93.240.0"/24;
+    "204.93.177.0"/24;
+    "199.27.128.0"/21;
+    "173.245.48.0"/20;
+    "103.21.244.0"/22;
+    "103.22.200.0"/22;
+    "103.31.4.0"/22;
+    "141.101.64.0"/18;
+    "108.162.192.0"/18;
+    "190.93.240.0"/20;
+    "188.114.96.0"/20;
+    "197.234.240.0"/22;
+    "198.41.128.0"/17;
+    "162.158.0.0"/15;
+    # https://www.cloudflare.com/ips-v6
+    "2400:cb00::"/32;
+    "2606:4700::"/32;
+    "2803:f800::"/32;
+    "2405:b500::"/32;
+    "2405:8100::"/32;
+}
+
+sub vcl_recv {
+    # Set the CF-Connecting-IP header
+    # If the client.ip is trusted, we leave the header alone if present.
+    if (req.http.CF-Connecting-IP) {
+        if (client.ip !~ official_cloudflare && client.ip !~ cloudflare) {
+            set req.http.CF-Connecting-IP = client.ip;
+        }
+    } else {
+        set req.http.CF-Connecting-IP = client.ip;
+    }
+}
+

--- /dev/null
+++ b/varnish-conf/v5/lib/mobile_cache.vcl
@@ -1,1 +1,20 @@
+# mobile_cache.vcl -- Separate cache for mobile clients
 
+# If the User-Agent looks like a mobile device, then we add the string
+# "mobile" to the hash_data.  This results in mobile devices having
+# a separate cache from non-mobile devices.
+#
+# Note that if the backend does anything more sophisticated than having
+# a "desktop" and a "mobile" version of pages (for example serving one
+# page to iPhones and another to Androids), this will not be desirable.
+# Also if the backend disagrees with this logic as far as what is a
+# "mobile" User-Agent, then we may save the wrong version of pages in
+# the cache.
+
+sub vcl_hash {
+    # General User-Agent list (anything that remotely looks like a mobile device)
+    if (req.http.User-Agent ~ "(?i)ipod|android|blackberry|phone|mobile|kindle|silk|fennec|tablet|webos|palm|windows ce|nokia|philips|samsung|sanyo|sony|panasonic|ericsson|alcatel|series60|series40|opera mini|opera mobi|au-mic|audiovox|avantgo|blazer|danger|docomo|epoc|ericy|i-mode|ipaq|midp-|mot-|netfront|nitro|pocket|portalmmm|rover|sie-|symbian|cldc-|j2me|up\.browser|up\.link|vodafone|wap1\.|wap2\.") {
+        hash_data("mobile");
+    }
+}
+

--- /dev/null
+++ b/varnish-conf/v5/lib/mobile_pass.vcl
@@ -1,1 +1,22 @@
+# mobile_pass.vcl -- Mobile pass-through support for Varnish
 
+# This simply bypasses the cache for anything that looks like a mobile
+# (or tablet) device.
+# Also passes through some requests that are specifically for the WordPress
+# Jetpack mobile plugin.
+
+sub vcl_recv {
+    # Rules specifically for the Jetpack Mobile module
+    if (req.url ~ "\?(.*&)?(ak_action|app-download)=") {
+        return(pass);
+    }
+    if (req.http.Cookie ~ "(^|;\s*)akm_mobile=") {
+        return(pass);
+    }
+
+    # General User-Agent blacklist (anything that remotely looks like a mobile device)
+    if (req.http.User-Agent ~ "(?i)ipod|android|blackberry|phone|mobile|kindle|silk|fennec|tablet|webos|palm|windows ce|nokia|philips|samsung|sanyo|sony|panasonic|ericsson|alcatel|series60|series40|opera mini|opera mobi|au-mic|audiovox|avantgo|blazer|danger|docomo|epoc|ericy|i-mode|ipaq|midp-|mot-|netfront|nitro|pocket|portalmmm|rover|sie-|symbian|cldc-|j2me|up\.browser|up\.link|vodafone|wap1\.|wap2\.") {
+        return(pass);
+    }
+}
+

--- /dev/null
+++ b/varnish-conf/v5/lib/purge.vcl
@@ -1,1 +1,106 @@
+# purge.vcl -- Cache Purge Library for Varnish
 
+# Regex purging
+# Treat the request URL as a regular expression.
+sub purge_regex {
+    ban("obj.http.X-VC-Req-URL ~ " + req.url + " && obj.http.X-VC-Req-Host == " + req.http.host);
+}
+
+# Exact purging
+# Use the exact request URL (including any query params)
+sub purge_exact {
+    ban("obj.http.X-VC-Req-URL == " + req.url + " && obj.http.X-VC-Req-Host == " + req.http.host);
+}
+
+# Page purging (default)
+# Use the exact request URL, but ignore any query params
+sub purge_page {
+    set req.url = regsub(req.url, "\?.*$", "");
+    ban("obj.http.X-VC-Req-URL-Base == " + req.url + " && obj.http.X-VC-Req-Host == " + req.http.host);
+}
+
+# The purge behavior can be controlled with the X-VC-Purge-Method header.
+#
+# Setting the X-VC-Purge-Method header to contain "regex" or "exact" will use
+# those respective behaviors.  Any other value for the X-Purge header will
+# use the default ("page") behavior.
+#
+# The X-VC-Purge-Method header is not case-sensitive.
+#
+# If no X-VC-Purge-Method header is set, the request url is inspected to attempt
+# a best guess as to what purge behavior is expected.  This should work for
+# most cases, although if you want to guarantee some behavior you should
+# always set the X-VC-Purge-Method header.
+
+sub vcl_recv {
+    set req.http.X-VC-My-Purge-Key = "ff93c3cb929cee86901c7eefc8088e9511c005492c6502a930360c02221cf8f4";
+    if (req.method == "PURGE") {
+        if (req.http.X-VC-Purge-Key == req.http.X-VC-My-Purge-Key) {
+            set req.http.X-VC-Purge-Key-Auth = "true";
+        } else {
+            set req.http.X-VC-Purge-Key-Auth = "false";
+        }
+        if (client.ip !~ purge && req.http.X-VC-Purge-Key-Auth != "true") {
+            return (synth(405, "Not allowed from " + client.ip));
+        }
+
+        if (req.http.X-VC-Purge-Method) {
+            if (req.http.X-VC-Purge-Method ~ "(?i)regex") {
+                call purge_regex;
+            } elsif (req.http.X-VC-Purge-Method ~ "(?i)exact") {
+                call purge_exact;
+            } else {
+                call purge_page;
+            }
+        } else {
+            # No X-VC-Purge-Method header was specified.
+            # Do our best to figure out which one they want.
+            if (req.url ~ "\.\*" || req.url ~ "^\^" || req.url ~ "\$$" || req.url ~ "\\[.?*+^$|()]") {
+                call purge_regex;
+            } elsif (req.url ~ "\?") {
+                call purge_exact;
+            } else {
+                call purge_page;
+            }
+        }
+        return (synth(200,"Purged " + req.url + " " + req.http.host));
+    }
+    unset req.http.X-VC-My-Purge-Key;
+    # unset Varnish Caching custom headers from client
+    unset req.http.X-VC-Cacheable;
+    unset req.http.X-VC-Debug;
+}
+
+sub vcl_backend_response {
+    set beresp.http.X-VC-Req-Host = bereq.http.host;
+    set beresp.http.X-VC-Req-URL = bereq.url;
+    set beresp.http.X-VC-Req-URL-Base = regsub(bereq.url, "\?.*$", "");
+}
+
+sub vcl_deliver {
+    unset resp.http.X-VC-Req-Host;
+    unset resp.http.X-VC-Req-URL;
+    unset resp.http.X-VC-Req-URL-Base;
+
+    if (obj.hits > 0) {
+        set resp.http.X-VC-Cache = "HIT";
+    } else {
+        set resp.http.X-VC-Cache = "MISS";
+    }
+
+    if (req.http.X-VC-Debug ~ "true" || resp.http.X-VC-Debug ~ "true") {
+        set resp.http.X-VC-Hash = req.http.hash;
+        if (req.http.X-VC-DebugMessage) {
+            set resp.http.X-VC-DebugMessage = req.http.X-VC-DebugMessage;
+        }
+    } else {
+        unset resp.http.X-VC-Enabled;
+        unset resp.http.X-VC-Cache;
+        unset resp.http.X-VC-Debug;
+        unset resp.http.X-VC-DebugMessage;
+        unset resp.http.X-VC-Cacheable;
+        unset resp.http.X-VC-Purge-Key-Auth;
+        unset resp.http.X-VC-TTL;
+    }
+}
+

--- /dev/null
+++ b/varnish-conf/v5/lib/static.vcl
@@ -1,1 +1,36 @@
+# static.vcl -- Static File Caching for Varnish
 
+sub vcl_recv {
+    if (req.method ~ "^(GET|HEAD)$" && req.url ~ "\.(jpg|jpeg|gif|png|ico|css|zip|tgz|gz|rar|bz2|pdf|txt|tar|wav|bmp|rtf|js|flv|swf|html|htm)(\?.*)?$") {
+        # if you use a subdomain for admin section, do not cache it
+        #if (req.http.host ~ "admin.yourdomain.com") {
+        #    set req.http.X-VC-Cacheable = "NO:Admin domain";
+        #    return(pass);
+        #}
+        # enable this if you want
+        #if (req.url ~ "debug") {
+        #    set req.http.X-VC-Debug = "true";
+        #}
+        # enable this if you need it
+        #if (req.url ~ "nocache") {
+        #    set req.http.X-VC-Cacheable = "NO:Not cacheable, nocache in URL";
+        #    return(pass);
+        #}
+        set req.url = regsub(req.url, "\?.*$", "");
+        # unset cookie only if no http auth
+        if (!req.http.Authorization) {
+            unset req.http.Cookie;
+        }
+        return(hash);
+    }
+}
+
+sub vcl_backend_response {
+    if (bereq.method ~ "^(GET|HEAD)$" && bereq.url ~ "\.(jpg|jpeg|gif|png|ico|css|zip|tgz|gz|rar|bz2|pdf|txt|tar|wav|bmp|rtf|js|flv|swf|html|htm)$") {
+        # overwrite ttl with X-VC-TTL
+        set beresp.http.X-VC-TTL = 24*60*60;
+        set beresp.ttl = std.duration(beresp.http.X-VC-TTL + "s", 0s);
+        set beresp.http.X-VC-Cacheable = "YES:Is cacheable, ttl: " + beresp.ttl;
+    }
+}
+

--- /dev/null
+++ b/varnish-conf/v5/lib/xforward.vcl
@@ -1,1 +1,17 @@
+# xforward.vcl -- X-Forwarded-For HTTP Headers
 
+# This should generally be loaded first to make sure that the headers
+# get set appropriately for all requests.  Note that when using this
+# you MUST NOT fall through to the VCL default handler for vcl_recv
+# since that will run the code again, resulting in the client.ip
+# being added twice.
+
+sub vcl_recv {
+    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;
+    }
+}
+

--- a/vcaching.php
+++ b/vcaching.php
@@ -3,14 +3,14 @@
 Plugin Name: Varnish Caching
 Plugin URI: http://wordpress.org/extend/plugins/vcaching/
 Description: WordPress Varnish Cache integration.
-Version: 1.5.5
+Version: 1.6
 Author: Razvan Stanga
 Author URI: http://git.razvi.ro/
 License: http://www.apache.org/licenses/LICENSE-2.0
 Text Domain: vcaching
 Network: true
 
-Copyright 2016: Razvan Stanga (email: varnish-caching@razvi.ro)
+Copyright 2017: Razvan Stanga (email: varnish-caching@razvi.ro)
 */
 
 class VCaching {
@@ -875,7 +875,7 @@
         add_settings_field($this->prefix . "varnish_version", __("Version", $this->plugin), array($this, $this->prefix . "varnish_version"), $this->prefix . 'download', "download");
 
         if(isset($_POST['option_page']) && $_POST['option_page'] == $this->prefix . 'download') {
-            $version = in_array($_POST['varnish_caching_varnish_version'], array(3,4)) ? $_POST['varnish_caching_varnish_version'] : 3;
+            $version = in_array($_POST['varnish_caching_varnish_version'], array(3,4,5)) ? $_POST['varnish_caching_varnish_version'] : 3;
             $tmpfile = tempnam("tmp", "zip");
             $zip = new ZipArchive();
             $zip->open($tmpfile, ZipArchive::OVERWRITE);
@@ -919,6 +919,7 @@
             <select name="varnish_caching_varnish_version" id="varnish_caching_varnish_version">
                 <option value="3">3</option>
                 <option value="4">4</option>
+                <option value="5">5</option>
             </select>
             <p class="description"><?=__('Varnish Cache version', $this->plugin)?></p>
         <?php
@@ -948,7 +949,7 @@
         } else if ($file == 'conf/backend.vcl') {
             if ($version == 3) {
                 $content = "";
-            } else if ($version == 4) {
+            } else if ($version == 4 || $version == 5) {
                 $content = "import directors;\n\n";
             }
             $backend = array();
@@ -980,7 +981,7 @@
                 $content .= "\nsub vcl_recv {\n";
                 $content .= "\tset req.backend = backends;\n";
                 $content .= "}\n";
-            } elseif ($version == 4) {
+            } elseif ($version == 4 || $version == 5) {
                 $content .= "\nsub vcl_init {\n";
                 $content .= "\tnew backends = directors.round_robin();\n";
                 $content .= $backend[4];

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