From 504df727809497f449bde1de770c7e9b925f02f4 Mon Sep 17 00:00:00 2001
From: Erick Hitter <ehitter@gmail.com>
Date: Fri, 28 Feb 2014 00:43:43 -0800
Subject: [PATCH] Better Purging
* Abstract Redis connection logic for reusability
* Abstract purging logic for reusability
* Create reusable purging logic
* Introduce single-page purging via the admin bar
See #5
---
redis-page-cache/redis-page-cache.php | 93 ++++++++++++++++++++++++---
1 file changed, 83 insertions(+), 10 deletions(-)
diff --git a/redis-page-cache/redis-page-cache.php b/redis-page-cache/redis-page-cache.php
index 9b1ed07..fd22a02 100644
--- a/redis-page-cache/redis-page-cache.php
+++ b/redis-page-cache/redis-page-cache.php
@@ -55,9 +55,16 @@ class Redis_Page_Cache {
* @return null
*/
private function __construct() {
+ // UI
add_action( 'admin_init', array( $this, 'register_options' ) );
add_action( 'admin_menu', array( $this, 'register_ui' ) );
+
+ // Automated invalidations
add_action( 'transition_post_status', array( $this, 'flush_cache' ), 10, 3 );
+
+ // Manual invalidations
+ add_action( 'admin_bar_menu', array( $this, 'admin_bar_menu' ), 999 );
+ add_action( 'wp_ajax_redis_page_cache_purge', array( $this, 'ajax_purge' ) );
}
/**
@@ -114,6 +121,21 @@ class Redis_Page_Cache {
return md5( 'v' . REDIS_PAGE_CACHE_CACHE_VERSION . '-' . $url );
}
+ /**
+ * Remove a specific URL from the Redis cache
+ *
+ * @param string $url
+ * @return null
+ */
+ private function purge( $url ) {
+ $redis = $this->redis();
+
+ $redis_key = $this->build_key( $url );
+ foreach ( array( '', 'M-', 'T-', ) as $prefix ) {
+ $redis->del( $prefix . $redis_key );
+ }
+ }
+
/**
* Register plugin's settings for proper sanitization
*
@@ -191,19 +213,70 @@ class Redis_Page_Cache {
*/
public function flush_cache( $new_status, $old_status, $post ) {
if ( in_array( 'publish', array( $new_status, $old_status ) ) ) {
- $redis = $this->redis();
+ $this->purge( get_permalink( $post->ID ) );
+ $this->purge( trailingslashit( get_home_url() ) );
+ }
+ }
- $redis_key = $this->build_key( get_permalink( $post->ID ) );
- foreach ( array( '', 'M-', 'T-', ) as $prefix ) {
- $redis->del( $prefix . $redis_key );
- }
+ /**
+ * Add a purge option to the admin bar for those with proper capabilities
+ *
+ * @return null
+ */
+ public function admin_bar_menu() {
+ global $wp_admin_bar;
- //refresh the front page
- $redis_key = $this->build_key( trailingslashit( get_home_url() ) );
- foreach ( array( '', 'M-', 'T-', ) as $prefix ) {
- $redis->del( $prefix . $redis_key );
- }
+ // In the admin, only show on the post editor
+ if ( is_admin() && 'post' !== get_current_screen()->base ) {
+ return;
+ }
+
+ // Only for Super Admins on multisite or Administrators on single site.
+ if ( ( is_multisite() && ! is_super_admin() ) || ! current_user_can( 'manage_options' ) ) {
+ return;
+ }
+
+ // What are we trying to clear?
+ $page_url = set_url_scheme( esc_url( $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'] ) );
+
+ $flush_url = add_query_arg( array(
+ 'action' => 'redis_page_cache_purge',
+ 'nonce' => wp_create_nonce( $page_url ),
+ 'url' => urlencode( $page_url ),
+ ), admin_url( 'admin-ajax.php' ) );
+
+ $wp_admin_bar->add_menu( array(
+ 'id' => 'redis-page-cache',
+ 'parent' => false,
+ 'title' => __( 'Clear Page Cache', 'redis-page-cache' ),
+ 'href' => $flush_url,
+ ) );
+ }
+
+ /**
+ * Purge a page from cache via an Ajax request
+ *
+ * @return null
+ */
+ public function ajax_purge() {
+ $url = esc_url_raw( urldecode( $_GET['url'] ) );
+ $redirect = add_query_arg( 'redis-page-cache-purge', 'failed', $url );
+
+ // Check nonce and referrer
+ if ( ! check_ajax_referer( $url, 'nonce', false ) ) {
+ wp_safe_redirect( $redirect, 302 );
}
+
+ // Only for Super Admins on multisite or Administrators on single site.
+ if ( ( is_multisite() && ! is_super_admin() ) || ! current_user_can( 'manage_options' ) ) {
+ wp_safe_redirect( $redirect, 302 );
+ }
+
+ // Checks passed, so we purge and redirect with success noted in the query string
+ $this->purge( $url );
+
+ $redirect = add_query_arg( 'redis-page-cache-purge', 'success', $redirect );
+ wp_safe_redirect( $redirect, 302 );
}
}
--
GitLab