From b1eb73dae4283fdbc08d110bb088b4b9d436cc47 Mon Sep 17 00:00:00 2001
From: Harold Kyle <harold@boxcarpress.com>
Date: Tue, 9 Apr 2013 15:40:03 -0400
Subject: [PATCH] exclude caching for requests with cookie name(s) starting
 with a certain string

---
 wp-ffpc-acache.php        | 25 +++++++++++++++++++++----
 wp-ffpc-class.php         | 37 +++++++++++++++++++++++++++++++++----
 wp-ffpc-nginx-sample.conf |  4 ++++
 wp-ffpc.php               |  1 +
 4 files changed, 59 insertions(+), 8 deletions(-)

diff --git a/wp-ffpc-acache.php b/wp-ffpc-acache.php
index 6428f8c..23c4da1 100644
--- a/wp-ffpc-acache.php
+++ b/wp-ffpc-acache.php
@@ -53,17 +53,34 @@ else
 	return false;
 
 /* no cache for for logged in users normally, only if enabled */
-if ( $wp_ffpc_config['cache_loggedin'] == 0 ) {
+if ( $wp_ffpc_config['cache_loggedin'] == 0  ||  $wp_ffpc_config['nocache_cookies'] ) {
+
+	$nocache_cookies = array();
+	if( $wp_ffpc_config['nocache_cookies'] ){
+		$nocache_cookies = array_map('trim',explode(",", $wp_ffpc_config['nocache_cookies'] ) );
+	}
+
 	foreach ($_COOKIE as $n=>$v) {
 		// test cookie makes to cache not work!!!
 		if ($n == 'wordpress_test_cookie') continue;
 		// wp 2.5 and wp 2.3 have different cookie prefix, skip cache if a post password cookie is present, also
-		if ( (substr($n, 0, 14) == 'wordpressuser_' || substr($n, 0, 10) == 'wordpress_' || substr($n, 0, 12) == 'wp-postpass_') && !$wp_ffpc_config['cache_loggedin'] ) {
-			return false;
+		if ( $wp_ffpc_config['cache_loggedin'] == 0 ) {
+			if ( (substr($n, 0, 14) == 'wordpressuser_' || substr($n, 0, 10) == 'wordpress_' || substr($n, 0, 12) == 'wp-postpass_') && !$wp_ffpc_config['cache_loggedin'] ) {
+				return false;
+			}
+		}
+		/* check for any matches to user-added cookies to no-cache */
+		if ( ! empty( $nocache_cookies ) ){
+			foreach ( $nocache_cookies as $nocache_cookie ) {
+				if( strpos( $n, $nocache_cookie ) === 0 ) {
+					return false;
+				}
+			}
 		}
 	}
 }
 
+
 /* canonical redirect storage */
 $wp_ffpc_redirect = null;
 
@@ -146,7 +163,7 @@ if ( !empty( $wp_ffpc_values['meta']['pingback'] ) )
 
 /* for debugging */
 if ( $wp_ffpc_config['response_header'] )
-	header( 'X-Cache-Engine: WP-FFPC with ' . $wp_ffpc_config['cache_type'] );
+	header( 'X-Cache-Engine: WP-FFPC with ' . $wp_ffpc_config['cache_type'] .' via PHP');
 
 /* HTML data */
 echo $wp_ffpc_values['data'];
diff --git a/wp-ffpc-class.php b/wp-ffpc-class.php
index 811158f..6d841a7 100644
--- a/wp-ffpc-class.php
+++ b/wp-ffpc-class.php
@@ -391,7 +391,7 @@ if ( ! class_exists( 'WP_FFPC' ) ) {
 					</dt>
 					<dd>
 						<input type="text" name="prefix_data" id="prefix_data" value="<?php echo $this->options['prefix_data']; ?>" />
-						<span class="description"><?php _e('Prefix for HTML content keys, can be used in nginx. If you are caching with nginx, you should update your nginx configuration and restart nginx after changing this value.', $this->plugin_constant); ?></span>
+						<span class="description"><?php _e('Prefix for HTML content keys, can be used in nginx.<br>If you are caching with nginx, you should update your nginx configuration and reload nginx after changing this value.', $this->plugin_constant); ?></span>
 					</dd>
 
 					<dt>
@@ -420,7 +420,7 @@ if ( ! class_exists( 'WP_FFPC' ) ) {
 					</dt>
 					<dd>
 						<input type="checkbox" name="log_info" id="log_info" value="1" <?php checked($this->options['log_info'],true); ?> />
-						<span class="description"><?php _e('Enables INFO level messages; carefull, plugin is really talkative. Requires PHP syslog function.', $this->plugin_constant); ?></span>
+						<span class="description"><?php _e('Enables INFO level messages; careful, plugin is really talkative. Requires PHP syslog function.', $this->plugin_constant); ?></span>
 					</dd>
 
 					<dt>
@@ -440,7 +440,7 @@ if ( ! class_exists( 'WP_FFPC' ) ) {
 					</dd>
 
 					<dt>
-						<label for="sync_protocols"><?php _e("Enable sync protocolls", $this->plugin_constant); ?></label>
+						<label for="sync_protocols"><?php _e("Enable sync protocols", $this->plugin_constant); ?></label>
 					</dt>
 					<dd>
 						<input type="checkbox" name="sync_protocols" id="sync_protocols" value="1" <?php checked($this->options['sync_protocols'],true); ?> />
@@ -501,6 +501,14 @@ if ( ! class_exists( 'WP_FFPC' ) ) {
 						<input type="checkbox" name="nocache_page" id="nocache_page" value="1" <?php checked($this->options['nocache_page'],true); ?> />
 						<span class="description"><?php _e('Exclude pages from caching.', $this->plugin_constant); ?></span>
 					</dd>
+
+					<dt>
+						<label for="nocache_cookies"><?php _e("Don't cache cookies", $this->plugin_constant); ?></label>
+					</dt>
+					<dd>
+						<input type="text" name="nocache_cookies" id="nocache_cookies" value="<?php if(isset( $this->options['nocache_cookies'] ) ) echo $this->options['nocache_cookies']; ?>" />
+						<span class="description"><?php _e('Exclude cookies names starting with this from caching. Separate multiple cookies names with commas.<br>If you are caching with nginx, you should update your nginx configuration and reload nginx after changing this value.', $this->plugin_constant); ?></span>
+					</dd>
 				</dl>
 				</fieldset>
 
@@ -519,7 +527,7 @@ if ( ! class_exists( 'WP_FFPC' ) ) {
 					</dt>
 					<dd>
 						<input type="checkbox" name="persistent" id="persistent" value="1" <?php checked($this->options['persistent'],true); ?> />
-						<span class="description"><?php _e('Make all memcache(d) connections persistent. Be carefull with this setting, always test the outcome.', $this->plugin_constant); ?></span>
+						<span class="description"><?php _e('Make all memcache(d) connections persistent. Be careful with this setting, always test the outcome.', $this->plugin_constant); ?></span>
 					</dd>
 				</dl>
 				</fieldset>
@@ -784,6 +792,27 @@ if ( ! class_exists( 'WP_FFPC' ) ) {
 			else
 				$nginx = str_replace ( 'LOGGEDIN_EXCEPTION' , '' , $nginx );
 
+			/* nginx can skip caching for visitors with certain cookies specified in the options */
+			if( $this->options['nocache_cookies'] ) {
+				$cookies = str_replace( ",","|", $this->options['nocache_cookies'] );
+				$cookies = str_replace( " ","", $cookies );
+				$cookie_exception = '# avoid cache for cookies specified
+				if ($http_cookie ~* ' . $cookies . ' ) {
+					set $memcached_request 0;
+				}';
+				$nginx = str_replace ( 'COOKIES_EXCEPTION' , $cookie_exception , $nginx );
+			} else {
+				$nginx = str_replace ( 'COOKIES_EXCEPTION' , '' , $nginx );
+			}
+
+			/* add custom response header if specified in the options */
+			if( $this->options['response_header'] ){
+				$response_header =  'add_header X-Cache-Engine "WP-FFPC with ' . $this->options['cache_type'] .' via nginx";';
+				$nginx = str_replace ( 'RESPONSE_HEADER' , $response_header , $nginx );
+			} else{
+				$nginx = str_replace ( 'RESPONSE_HEADER' , '' , $nginx );
+			}
+
 			return $nginx;
 		}
 
diff --git a/wp-ffpc-nginx-sample.conf b/wp-ffpc-nginx-sample.conf
index 16817f3..372b8f9 100644
--- a/wp-ffpc-nginx-sample.conf
+++ b/wp-ffpc-nginx-sample.conf
@@ -144,7 +144,10 @@ MEMCACHED_SERVERS
 
 				LOGGEDIN_EXCEPTION
 
+				COOKIES_EXCEPTION
+
 				if ( $memcached_request = 1) {
+						RESPONSE_HEADER
 						memcached_pass memcached-servers;
 						error_page 404 = @rewrites;
 				}
@@ -156,6 +159,7 @@ MEMCACHED_SERVERS
 
 		## rewrite rules
 		location @rewrites {
+				add_header X-Cache-Engine "";
 				rewrite ^ /index.php?$args last;
 		}
 
diff --git a/wp-ffpc.php b/wp-ffpc.php
index 6008330..8a18386 100644
--- a/wp-ffpc.php
+++ b/wp-ffpc.php
@@ -43,6 +43,7 @@ $wp_ffpc_defaults = array (
 	'nocache_archive' => false,
 	'nocache_single' => false,
 	'nocache_page' => false,
+	'nocache_cookies' => false,
 	'sync_protocols' => false,
 	'persistent' => false,
 	'response_header' => false,