<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head><meta http-equiv="content-type" content="text/html; charset=utf-8" />
<title>[53763] trunk: Cache API: Add `wp_cache_flush_group` function.</title>
</head>
<body>

<style type="text/css"><!--
#msg dl.meta { border: 1px #006 solid; background: #369; padding: 6px; color: #fff; }
#msg dl.meta dt { float: left; width: 6em; font-weight: bold; }
#msg dt:after { content:':';}
#msg dl, #msg dt, #msg ul, #msg li, #header, #footer, #logmsg { font-family: verdana,arial,helvetica,sans-serif; font-size: 10pt;  }
#msg dl a { font-weight: bold}
#msg dl a:link    { color:#fc3; }
#msg dl a:active  { color:#ff0; }
#msg dl a:visited { color:#cc6; }
h3 { font-family: verdana,arial,helvetica,sans-serif; font-size: 10pt; font-weight: bold; }
#msg pre { white-space: pre-line; overflow: auto; background: #ffc; border: 1px #fa0 solid; padding: 6px; }
#logmsg { background: #ffc; border: 1px #fa0 solid; padding: 1em 1em 0 1em; }
#logmsg p, #logmsg pre, #logmsg blockquote { margin: 0 0 1em 0; }
#logmsg p, #logmsg li, #logmsg dt, #logmsg dd { line-height: 14pt; }
#logmsg h1, #logmsg h2, #logmsg h3, #logmsg h4, #logmsg h5, #logmsg h6 { margin: .5em 0; }
#logmsg h1:first-child, #logmsg h2:first-child, #logmsg h3:first-child, #logmsg h4:first-child, #logmsg h5:first-child, #logmsg h6:first-child { margin-top: 0; }
#logmsg ul, #logmsg ol { padding: 0; list-style-position: inside; margin: 0 0 0 1em; }
#logmsg ul { text-indent: -1em; padding-left: 1em; }#logmsg ol { text-indent: -1.5em; padding-left: 1.5em; }
#logmsg > ul, #logmsg > ol { margin: 0 0 1em 0; }
#logmsg pre { background: #eee; padding: 1em; }
#logmsg blockquote { border: 1px solid #fa0; border-left-width: 10px; padding: 1em 1em 0 1em; background: white;}
#logmsg dl { margin: 0; }
#logmsg dt { font-weight: bold; }
#logmsg dd { margin: 0; padding: 0 0 0.5em 0; }
#logmsg dd:before { content:'\00bb';}
#logmsg table { border-spacing: 0px; border-collapse: collapse; border-top: 4px solid #fa0; border-bottom: 1px solid #fa0; background: #fff; }
#logmsg table th { text-align: left; font-weight: normal; padding: 0.2em 0.5em; border-top: 1px dotted #fa0; }
#logmsg table td { text-align: right; border-top: 1px dotted #fa0; padding: 0.2em 0.5em; }
#logmsg table thead th { text-align: center; border-bottom: 1px solid #fa0; }
#logmsg table th.Corner { text-align: left; }
#logmsg hr { border: none 0; border-top: 2px dashed #fa0; height: 1px; }
#header, #footer { color: #fff; background: #636; border: 1px #300 solid; padding: 6px; }
#patch { width: 100%; }
#patch h4 {font-family: verdana,arial,helvetica,sans-serif;font-size:10pt;padding:8px;background:#369;color:#fff;margin:0;}
#patch .propset h4, #patch .binary h4 {margin:0;}
#patch pre {padding:0;line-height:1.2em;margin:0;}
#patch .diff {width:100%;background:#eee;padding: 0 0 10px 0;overflow:auto;}
#patch .propset .diff, #patch .binary .diff  {padding:10px 0;}
#patch span {display:block;padding:0 10px;}
#patch .modfile, #patch .addfile, #patch .delfile, #patch .propset, #patch .binary, #patch .copfile {border:1px solid #ccc;margin:10px 0;}
#patch ins {background:#dfd;text-decoration:none;display:block;padding:0 10px;}
#patch del {background:#fdd;text-decoration:none;display:block;padding:0 10px;}
#patch .lines, .info {color:#888;background:#fff;}
--></style>
<div id="msg">
<dl class="meta" style="font-size: 105%">
<dt style="float: left; width: 6em; font-weight: bold">Revision</dt> <dd><a style="font-weight: bold" href="https://core.trac.wordpress.org/changeset/53763">53763</a><script type="application/ld+json">{"@context":"http://schema.org","@type":"EmailMessage","description":"Review this Commit","action":{"@type":"ViewAction","url":"https://core.trac.wordpress.org/changeset/53763","name":"Review Commit"}}</script></dd>
<dt style="float: left; width: 6em; font-weight: bold">Author</dt> <dd>spacedmonkey</dd>
<dt style="float: left; width: 6em; font-weight: bold">Date</dt> <dd>2022-07-22 20:50:31 +0000 (Fri, 22 Jul 2022)</dd>
</dl>

<pre style='padding-left: 1em; margin: 2em 0; border-left: 2px solid #ccc; line-height: 1.25; font-size: 105%; font-family: sans-serif'>Cache API: Add `wp_cache_flush_group` function. 

Add a new plugable function called `wp_cache_flush_group`, that will allow developers to clear whole cache groups with a single call. Developers can detect if their current implementation of an object cache supports flushing by group, by calling `wp_cache_supports_group_flush` which returns true if it is supported. If the developers of the object cache drop-in has not implemented `wp_cache_flush_group` and `wp_cache_supports_group_flush`, these functions are polyfilled and `wp_cache_supports_group_flush` defaults to false.

Props Spacedmonkey, filosofo, ryan, sc0ttkclark, SergeyBiryukov, scribu, Ste_95, dd32, dhilditch, dougal, lucasbustamante, dg12345, tillkruess, peterwilsoncc, flixos90, pbearne.
Fixes <a href="https://core.trac.wordpress.org/ticket/4476">#4476</a>.</pre>

<h3>Modified Paths</h3>
<ul>
<li><a href="#trunksrcwpincludescachecompatphp">trunk/src/wp-includes/cache-compat.php</a></li>
<li><a href="#trunksrcwpincludescachephp">trunk/src/wp-includes/cache.php</a></li>
<li><a href="#trunksrcwpincludesclasswpobjectcachephp">trunk/src/wp-includes/class-wp-object-cache.php</a></li>
<li><a href="#trunktestsphpunitincludesobjectcachephp">trunk/tests/phpunit/includes/object-cache.php</a></li>
<li><a href="#trunktestsphpunittestscachephp">trunk/tests/phpunit/tests/cache.php</a></li>
<li><a href="#trunktestsphpunittestspluggablephp">trunk/tests/phpunit/tests/pluggable.php</a></li>
</ul>

</div>
<div id="patch">
<h3>Diff</h3>
<a id="trunksrcwpincludescachecompatphp"></a>
<div class="modfile"><h4 style="background-color: #eee; color: inherit; margin: 1em 0; padding: 1.3em; font-size: 115%">Modified: trunk/src/wp-includes/cache-compat.php</h4>
<pre class="diff"><span>
<span class="info" style="display: block; padding: 0 10px; color: #888">--- trunk/src/wp-includes/cache-compat.php    2022-07-22 17:09:05 UTC (rev 53762)
+++ trunk/src/wp-includes/cache-compat.php      2022-07-22 20:50:31 UTC (rev 53763)
</span><span class="lines" style="display: block; padding: 0 10px; color: #888">@@ -141,3 +141,49 @@
</span><span class="cx" style="display: block; padding: 0 10px">                return wp_using_ext_object_cache() ? false : wp_cache_flush();
</span><span class="cx" style="display: block; padding: 0 10px">        }
</span><span class="cx" style="display: block; padding: 0 10px"> endif;
</span><ins style="background-color: #dfd; text-decoration:none; display:block; padding: 0 10px">+
+if ( ! function_exists( 'wp_cache_flush_group' ) ) :
+       /**
+        * Removes all cache items in a group, if the object cache implementation supports it.
+        * Before calling this method, always check for group flushing support using the
+        * `wp_cache_supports_group_flush()` method.
+        *
+        * @since 6.1.0
+        *
+        * @see WP_Object_Cache::flush_group()
+        * @global WP_Object_Cache $wp_object_cache Object cache global instance.
+        *
+        * @param string $group Name of group to remove from cache.
+        * @return bool True if group was flushed, false otherwise.
+        */
+       function wp_cache_flush_group( $group ) {
+               global $wp_object_cache;
+
+               if ( ! wp_cache_supports_group_flush() ) {
+                       _doing_it_wrong(
+                               __FUNCTION__,
+                               __( 'Your object cache implementation does not support flushing individual groups.' ),
+                               '6.1.0'
+                       );
+
+                       return false;
+               }
+
+               return $wp_object_cache->flush_group( $group );
+       }
+endif;
+
+if ( ! function_exists( 'wp_cache_supports_group_flush' ) ) :
+       /**
+        * Whether the object cache implementation supports flushing individual cache groups.
+        *
+        * @since 6.1.0
+        *
+        * @see WP_Object_Cache::flush_group()
+        *
+        * @return bool True if group flushing is supported, false otherwise.
+        */
+       function wp_cache_supports_group_flush() {
+               return false;
+       }
+endif;
</ins></span></pre></div>
<a id="trunksrcwpincludescachephp"></a>
<div class="modfile"><h4 style="background-color: #eee; color: inherit; margin: 1em 0; padding: 1.3em; font-size: 115%">Modified: trunk/src/wp-includes/cache.php</h4>
<pre class="diff"><span>
<span class="info" style="display: block; padding: 0 10px; color: #888">--- trunk/src/wp-includes/cache.php   2022-07-22 17:09:05 UTC (rev 53762)
+++ trunk/src/wp-includes/cache.php     2022-07-22 20:50:31 UTC (rev 53763)
</span><span class="lines" style="display: block; padding: 0 10px; color: #888">@@ -23,6 +23,19 @@
</span><span class="cx" style="display: block; padding: 0 10px"> }
</span><span class="cx" style="display: block; padding: 0 10px"> 
</span><span class="cx" style="display: block; padding: 0 10px"> /**
</span><ins style="background-color: #dfd; text-decoration:none; display:block; padding: 0 10px">+ * Whether the object cache implementation supports flushing individual cache groups.
+ *
+ * @since 6.1.0
+ *
+ * @see WP_Object_Cache::flush_group()
+ *
+ * @return bool True if group flushing is supported, false otherwise.
+ */
+function wp_cache_supports_group_flush() {
+       return true;
+}
+
+/**
</ins><span class="cx" style="display: block; padding: 0 10px">  * Adds data to the cache, if the cache key doesn't already exist.
</span><span class="cx" style="display: block; padding: 0 10px">  *
</span><span class="cx" style="display: block; padding: 0 10px">  * @since 2.0.0
</span><span class="lines" style="display: block; padding: 0 10px; color: #888">@@ -282,6 +295,25 @@
</span><span class="cx" style="display: block; padding: 0 10px"> }
</span><span class="cx" style="display: block; padding: 0 10px"> 
</span><span class="cx" style="display: block; padding: 0 10px"> /**
</span><ins style="background-color: #dfd; text-decoration:none; display:block; padding: 0 10px">+ * Removes all cache items in a group, if the object cache implementation supports it.
+ * Before calling this method, always check for group flushing support using the
+ * `wp_cache_supports_group_flush()` method.
+ *
+ * @since 6.1.0
+ *
+ * @see WP_Object_Cache::flush_group()
+ * @global WP_Object_Cache $wp_object_cache Object cache global instance.
+ *
+ * @param string $group Name of group to remove from cache.
+ * @return bool True if group was flushed, false otherwise.
+ */
+function wp_cache_flush_group( $group ) {
+       global $wp_object_cache;
+
+       return $wp_object_cache->flush_group( $group );
+}
+
+/**
</ins><span class="cx" style="display: block; padding: 0 10px">  * Closes the cache.
</span><span class="cx" style="display: block; padding: 0 10px">  *
</span><span class="cx" style="display: block; padding: 0 10px">  * This function has ceased to do anything since WordPress 2.5. The
</span></span></pre></div>
<a id="trunksrcwpincludesclasswpobjectcachephp"></a>
<div class="modfile"><h4 style="background-color: #eee; color: inherit; margin: 1em 0; padding: 1.3em; font-size: 115%">Modified: trunk/src/wp-includes/class-wp-object-cache.php</h4>
<pre class="diff"><span>
<span class="info" style="display: block; padding: 0 10px; color: #888">--- trunk/src/wp-includes/class-wp-object-cache.php   2022-07-22 17:09:05 UTC (rev 53762)
+++ trunk/src/wp-includes/class-wp-object-cache.php     2022-07-22 20:50:31 UTC (rev 53763)
</span><span class="lines" style="display: block; padding: 0 10px; color: #888">@@ -291,6 +291,20 @@
</span><span class="cx" style="display: block; padding: 0 10px">        }
</span><span class="cx" style="display: block; padding: 0 10px"> 
</span><span class="cx" style="display: block; padding: 0 10px">        /**
</span><ins style="background-color: #dfd; text-decoration:none; display:block; padding: 0 10px">+         * Removes all cache items in a group.
+        *
+        * @since 6.1.0
+        *
+        * @param string $group Name of group to remove from cache.
+        * @return true Always returns true.
+        */
+       public function flush_group( $group ) {
+               unset( $this->cache[ $group ] );
+
+               return true;
+       }
+
+       /**
</ins><span class="cx" style="display: block; padding: 0 10px">          * Retrieves the cache contents, if it exists.
</span><span class="cx" style="display: block; padding: 0 10px">         *
</span><span class="cx" style="display: block; padding: 0 10px">         * The contents will be first attempted to be retrieved by searching by the
</span></span></pre></div>
<a id="trunktestsphpunitincludesobjectcachephp"></a>
<div class="modfile"><h4 style="background-color: #eee; color: inherit; margin: 1em 0; padding: 1.3em; font-size: 115%">Modified: trunk/tests/phpunit/includes/object-cache.php</h4>
<pre class="diff"><span>
<span class="info" style="display: block; padding: 0 10px; color: #888">--- trunk/tests/phpunit/includes/object-cache.php     2022-07-22 17:09:05 UTC (rev 53762)
+++ trunk/tests/phpunit/includes/object-cache.php       2022-07-22 20:50:31 UTC (rev 53763)
</span><span class="lines" style="display: block; padding: 0 10px; color: #888">@@ -746,6 +746,17 @@
</span><span class="cx" style="display: block; padding: 0 10px"> }
</span><span class="cx" style="display: block; padding: 0 10px"> 
</span><span class="cx" style="display: block; padding: 0 10px"> /**
</span><ins style="background-color: #dfd; text-decoration:none; display:block; padding: 0 10px">+ * Whether the object cache implementation supports flushing individual cache groups.
+ *
+ * @since 6.1.0
+ *
+ * @return bool True if group flushing is supported, false otherwise.
+ */
+function wp_cache_supports_group_flush() {
+       return false;
+}
+
+/**
</ins><span class="cx" style="display: block; padding: 0 10px">  * Adds a group or set of groups to the list of non-persistent groups.
</span><span class="cx" style="display: block; padding: 0 10px">  *
</span><span class="cx" style="display: block; padding: 0 10px">  * @param string|array $groups A group or an array of groups to add.
</span></span></pre></div>
<a id="trunktestsphpunittestscachephp"></a>
<div class="modfile"><h4 style="background-color: #eee; color: inherit; margin: 1em 0; padding: 1.3em; font-size: 115%">Modified: trunk/tests/phpunit/tests/cache.php</h4>
<pre class="diff"><span>
<span class="info" style="display: block; padding: 0 10px; color: #888">--- trunk/tests/phpunit/tests/cache.php       2022-07-22 17:09:05 UTC (rev 53762)
+++ trunk/tests/phpunit/tests/cache.php 2022-07-22 20:50:31 UTC (rev 53763)
</span><span class="lines" style="display: block; padding: 0 10px; color: #888">@@ -415,4 +415,36 @@
</span><span class="cx" style="display: block; padding: 0 10px"> 
</span><span class="cx" style="display: block; padding: 0 10px">                $this->assertSame( $expected, $found );
</span><span class="cx" style="display: block; padding: 0 10px">        }
</span><ins style="background-color: #dfd; text-decoration:none; display:block; padding: 0 10px">+
+       /**
+        * @ticket 4476
+        * @ticket 9773
+        *
+        * test wp_cache_flush_group
+        *
+        * @covers ::wp_cache_flush_group
+        */
+       public function test_wp_cache_flush_group() {
+               $key = 'my-key';
+               $val = 'my-val';
+
+               wp_cache_set( $key, $val, 'group-test' );
+               wp_cache_set( $key, $val, 'group-kept' );
+
+               $this->assertSame( $val, wp_cache_get( $key, 'group-test' ), 'test_wp_cache_flush_group: group-test should contain my-val' );
+
+               if ( wp_using_ext_object_cache() ) {
+                       $this->setExpectedIncorrectUsage( 'wp_cache_flush_group' );
+               }
+
+               $results = wp_cache_flush_group( 'group-test' );
+
+               if ( wp_using_ext_object_cache() ) {
+                       $this->assertFalse( $results );
+               } else {
+                       $this->assertTrue( $results );
+                       $this->assertFalse( wp_cache_get( $key, 'group-test' ), 'test_wp_cache_flush_group: group-test should return false' );
+                       $this->assertSame( $val, wp_cache_get( $key, 'group-kept' ), 'test_wp_cache_flush_group: group-kept should still contain my-val' );
+               }
+       }
</ins><span class="cx" style="display: block; padding: 0 10px"> }
</span></span></pre></div>
<a id="trunktestsphpunittestspluggablephp"></a>
<div class="modfile"><h4 style="background-color: #eee; color: inherit; margin: 1em 0; padding: 1.3em; font-size: 115%">Modified: trunk/tests/phpunit/tests/pluggable.php</h4>
<pre class="diff"><span>
<span class="info" style="display: block; padding: 0 10px; color: #888">--- trunk/tests/phpunit/tests/pluggable.php   2022-07-22 17:09:05 UTC (rev 53762)
+++ trunk/tests/phpunit/tests/pluggable.php     2022-07-22 20:50:31 UTC (rev 53763)
</span><span class="lines" style="display: block; padding: 0 10px; color: #888">@@ -268,6 +268,7 @@
</span><span class="cx" style="display: block; padding: 0 10px"> 
</span><span class="cx" style="display: block; padding: 0 10px">                                        // wp-includes/cache.php:
</span><span class="cx" style="display: block; padding: 0 10px">                                        'wp_cache_init'                      => array(),
</span><ins style="background-color: #dfd; text-decoration:none; display:block; padding: 0 10px">+                                        'wp_cache_supports_group_flush'      => array(),
</ins><span class="cx" style="display: block; padding: 0 10px">                                         'wp_cache_add'                       => array(
</span><span class="cx" style="display: block; padding: 0 10px">                                                'key',
</span><span class="cx" style="display: block; padding: 0 10px">                                                'data',
</span><span class="lines" style="display: block; padding: 0 10px; color: #888">@@ -327,6 +328,7 @@
</span><span class="cx" style="display: block; padding: 0 10px">                                        ),
</span><span class="cx" style="display: block; padding: 0 10px">                                        'wp_cache_flush'                     => array(),
</span><span class="cx" style="display: block; padding: 0 10px">                                        'wp_cache_flush_runtime'             => array(),
</span><ins style="background-color: #dfd; text-decoration:none; display:block; padding: 0 10px">+                                        'wp_cache_flush_group'               => array( 'group' ),
</ins><span class="cx" style="display: block; padding: 0 10px">                                         'wp_cache_close'                     => array(),
</span><span class="cx" style="display: block; padding: 0 10px">                                        'wp_cache_add_global_groups'         => array( 'groups' ),
</span><span class="cx" style="display: block; padding: 0 10px">                                        'wp_cache_add_non_persistent_groups' => array( 'groups' ),
</span></span></pre>
</div>
</div>

</body>
</html>