# Specify VCL new 4.0 format.
vcl 4.0;

# Imports
import std;

# Default backend definition. Set this to point to your content server.
backend default {
    .host = "192.168.168.11";
    ##.port = "8080";
    .port = "80";
}


acl aclPurge {
    "127.0.0.1";
    "localhost";
    "192.168.168.11";

}
acl aclBanned {
	# some specific malicious ip addresses
	"81.82.83.84";
	"31.5.89.4";
}

sub vcl_recv {
	### DOC
	# https://www.varnish-cache.org/docs/4.0/users-guide/vcl-built-in-subs.html#vcl-recv
	# http://www.mediawiki.org/wiki/Manual:Varnish_caching#Configuring_Varnish_4.x
	# - The builtin VCL is always called afterwards.
	# - Happens before we check if we have this in cache already.
	# - Typically you clean up the request here, adjusting headers, managing cookies, rewriting the request, etc.

    ### vmod std:
    #   - std.log(str): Logs a string to the shared memory log, using VSL tag VCL_Log
    #   - varnishlog -i VCL_Log

	###
	### Allow purging
	###
	#     Tip: it only purges the current cache entry (to purge the whole cache: do service restart instead)
	if (req.method == "PURGE") {
		if (!client.ip ~ aclPurge) {
		    return (synth(405, "This IP is not allowed to send PURGE requests."));
		}
		return (purge);
	}

	###
	### Banning Logic (replacing the Wordpress Plugin WP-Ban)
	###

	# IP Addresses 192.168.*.
	if (client.ip ~ aclBanned) {
		return (synth(403, "Forbidden"));
    }

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

	### Do not Authorized requests.
	if (req.http.Authorization) {
		return(pass); // DO NOT CACHE
	}

	### Pass any requests with the "If-None-Match" header directly.
	if (req.http.If-None-Match) {
		return(pass); // DO NOT CACHE
	}

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

	### Only cache GET or HEAD requests. This makes sure the POST (and OPTIONS) requests are always passed.
	if (req.method != "GET" && req.method != "HEAD") {
		return (pass); // DO NOT CACHE
	}


	### 
	### Request URL
	###

	# Apache: disable caching for the Apache2 server status page
	if (req.url ~ "^/server-status") {
		# do not use the cache
		return(pass); // DO NOT CACHE
	}
    # Nginx: disable caching for the nginx server status page
    if (req.url ~ "^/nginx_status") {
            # do not use the cache
            return(pass); // DO NOT CACHE
    }
	### Static files: Do not cache PDF, XML, ... files (=static & huge and no use caching them - in all Vary: variations!)
	if (req.url ~ "\.(doc|mp3|pdf|tif|tiff|xml)(\?.*|)$") {
		return(pass); // DO NOT CACHE
	}

	# Wordpress: disable caching for some parts of the backend (mostly admin stuff)
	# and WP search results.
	if (
		req.url ~ "^/wp-(login|admin)" || req.url ~ "/wp-cron.php" || req.url ~ "/wp-content/uploads/"
	 || req.url ~ "preview=true"       || req.url ~ "xmlrpc.php"   || req.url ~ "\?s="
	) {
		# do not use the cache
		return(pass); // DO NOT CACHE
	}

	# Development: my /tryme/ folder with test scripts
	if (req.url ~ "^/tryme/") {
		# do not use the cache
		return(pass); // DO NOT CACHE
	}

	# WooCommerce
	if (req.url ~ "\?add-to-cart=") {
		# do not use the cache
		return(pass); // DO NOT CACHE
	}

	# Kick DFind requests
	if (req.url ~ "^/w00tw00t") {
		return (synth(404, "Not Found"));
	}


	### 
	### http header Cookie
	### 	Remove some cookies (if found).
	###
	# https://www.varnish-cache.org/docs/4.0/users-guide/increasing-your-hitrate.html#cookies

	# Unset the header for static files
	if (req.url ~ "\.(css|flv|gif|htm|html|ico|jpeg|jpg|js|mp3|mp4|pdf|png|swf|tif|tiff|xml)(\?.*|)$") {
		unset req.http.Cookie;
	}

	if (req.http.cookie) {
		# Google Analytics
		set req.http.Cookie = regsuball( req.http.Cookie, "(^|;\s*)(__utm[a-z]+)=([^;]*)", "");
		set req.http.Cookie = regsuball( req.http.Cookie, "(^|;\s*)(_ga)=([^;]*)", "");

		# Quant Capital
		set req.http.Cookie = regsuball( req.http.Cookie, "(^|;\s*)(__qc[a-z]+)=([^;]*)", "");

		# __gad __gads
		set req.http.Cookie = regsuball( req.http.Cookie, "(^|;\s*)(__gad[a-z]+)=([^;]*)", "");

		# Google Cookie consent (client javascript cookie)
		set req.http.Cookie = regsuball( req.http.Cookie, "(^|;\s*)(displayCookieConsent)=([^;]*)", "");

		# Other known Cookies: remove them (if found).
		set req.http.Cookie = regsuball( req.http.Cookie, "(^|;\s*)(__CT_Data)=([^;]*)", "");
		set req.http.Cookie = regsuball( req.http.Cookie, "(^|;\s*)(WRIgnore|WRUID)=([^;]*)", "");


		# PostAction: Remove (once and if found) a ";" prefix followed by 0..n whitespaces.
		# INFO \s* = 0..n whitespace characters
		set req.http.Cookie = regsub( req.http.Cookie, "^;\s*", "" );

		# PostAction: Unset the header if it is empty or 0..n whitespaces.
		if ( req.http.cookie ~ "^\s*$" ) {
			unset req.http.Cookie;
		}
	}


	###
	### Normalize the Accept-Language header
	### We do not need a cache for each language-country combination! Just keep en-* and nl-* for future use.
	### https://www.varnish-cache.org/docs/4.0/users-guide/increasing-your-hitrate.html#http-vary
	if (req.http.Accept-Language) {
		if (req.http.Accept-Language ~ "^en") {
			set req.http.Accept-Language = "en";
		} elsif (req.http.Accept-Language ~ "^nl") {
			set req.http.Accept-Language = "nl";
		} else {
			# Unknown language. Set it to English.
			set req.http.Accept-Language = "en";
		}
	}


	###
	### Varnish v4: vcl_recv must now return hash instead of lookup
	return(hash);
}

sub vcl_backend_response {
	# Happens after we have read the response headers from the backend.
	# Here you clean the response headers, removing silly Set-Cookie headers
	# and other mistakes your backend does.
        set beresp.ttl = 10s;
        set beresp.grace = 1h;

	# main variable = beresp.
}

sub vcl_deliver {
	# Happens when we have all the pieces we need, and are about to send the
	# response to the client. You can do accounting or modifying the final object here.

	# main variable = resp.

#	set resp.http.Server = "nginx";
#	set resp.http.X-Powered-By = "root.bg";
	unset resp.http.Server;
	unset resp.http.X-Powered-By;
}

sub vcl_pipe {
	# https://www.varnish-software.com/blog/using-pipe-varnish
	# 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, 
	# then make sure to use this: set req.http.connection = "close";
	# (This code is not necessary if you do not do any request rewriting.)

	set req.http.connection = "close";
}
###EndOf: .vcl