Changeset 55148

Timestamp:

01/26/2023 11:01:10 PM (21 months ago)

Author:

flixos90

Message:

Editor: Use a non-persistent object cache instead of transient in wp_get_global_stylesheet().

This changeset is part of a greater effort to enhance the caching strategy for theme.json based data. Similar to [55138], the cache is currently ignored when WP_DEBUG is on to avoid interrupting the theme developer's workflow.

Props oandregal, spacedmonkey, hellofromtonya, flixos90, ironprogrammer, azaozz, aristath, costdev, mcsf.
Fixes #56910.

Location:

trunk

Files:

• src/wp-includes/global-styles-and-settings.php (modified) (3 diffs)
• src/wp-includes/load.php (modified) (1 diff)
• src/wp-includes/ms-blogs.php (modified) (2 diffs)
• tests/phpunit/includes/abstract-testcase.php (modified) (1 diff)
• tests/phpunit/tests/theme/wpGetGlobalStylesheet.php (modified) (1 diff)

trunk/src/wp-includes/global-styles-and-settings.php

@@ -86 +86 @@
  */
 function wp_get_global_stylesheet( $types = array() ) {
-    // Return cached value if it can be used and exists.
-    // It's cached by theme to make sure that theme switching clears the cache.
-    $can_use_cached = (
-        ( empty( $types ) ) &&
-        ( ! defined( 'WP_DEBUG' ) || ! WP_DEBUG ) &&
-        ( ! defined( 'SCRIPT_DEBUG' ) || ! SCRIPT_DEBUG ) &&
-        ( ! defined( 'REST_REQUEST' ) || ! REST_REQUEST ) &&
-        ! is_admin()
-    );
-    $transient_name = 'global_styles_' . get_stylesheet();
+    /*
+     * Ignore cache when `WP_DEBUG` is enabled, so it doesn't interfere with the theme
+     * developer's workflow.
+     *
+     * @todo Replace `WP_DEBUG` once an "in development mode" check is available in Core.
+     */
+    $can_use_cached = empty( $types ) && ! WP_DEBUG;
+
+    /*
+     * By using the 'theme_json' group, this data is marked to be non-persistent across requests.
+     * @see `wp_cache_add_non_persistent_groups()`.
+     *
+     * The rationale for this is to make sure derived data from theme.json
+     * is always fresh from the potential modifications done via hooks
+     * that can use dynamic data (modify the stylesheet depending on some option,
+     * settings depending on user permissions, etc.).
+     * See some of the existing hooks to modify theme.json behavior:
+     * @see https://make.wordpress.org/core/2022/10/10/filters-for-theme-json-data/
+     *
+     * A different alternative considered was to invalidate the cache upon certain
+     * events such as options add/update/delete, user meta, etc.
+     * It was judged not enough, hence this approach.
+     * @see https://github.com/WordPress/gutenberg/pull/45372
+     */
+    $cache_group = 'theme_json';
+    $cache_key   = 'wp_get_global_stylesheet';
     if ( $can_use_cached ) {
-        $cached = get_transient( $transient_name );
+        $cached = wp_cache_get( $cache_key, $cache_group );
         if ( $cached ) {
             return $cached;
@@ -153 +169 @@
 
     $stylesheet = $styles_variables . $styles_rest;
-
     if ( $can_use_cached ) {
-        // Cache for a minute.
-        // This cache doesn't need to be any longer, we only want to avoid spikes on high-traffic sites.
-        set_transient( $transient_name, $stylesheet, MINUTE_IN_SECONDS );
+        wp_cache_set( $cache_key, $stylesheet, $cache_group );
     }
 
@@ -304 +317 @@
  */
 function wp_clean_theme_json_cache() {
+    wp_cache_delete( 'wp_get_global_stylesheet', 'theme_json' );
     WP_Theme_JSON_Resolver::clean_cached_data();
 }

trunk/src/wp-includes/load.php

@@ -754 +754 @@
         );
 
-        wp_cache_add_non_persistent_groups( array( 'counts', 'plugins' ) );
+        wp_cache_add_non_persistent_groups( array( 'counts', 'plugins', 'theme_json' ) );
     }
 

trunk/src/wp-includes/ms-blogs.php

@@ -576 +576 @@
             }
 
-            wp_cache_add_non_persistent_groups( array( 'counts', 'plugins' ) );
+            wp_cache_add_non_persistent_groups( array( 'counts', 'plugins', 'theme_json' ) );
         }
     }
@@ -667 +667 @@
             }
 
-            wp_cache_add_non_persistent_groups( array( 'counts', 'plugins' ) );
+            wp_cache_add_non_persistent_groups( array( 'counts', 'plugins', 'theme_json' ) );
         }
     }

trunk/tests/phpunit/includes/abstract-testcase.php

@@ -402 +402 @@
         );
 
-        wp_cache_add_non_persistent_groups( array( 'counts', 'plugins' ) );
+        wp_cache_add_non_persistent_groups( array( 'counts', 'plugins', 'theme_json' ) );
     }
 

trunk/tests/phpunit/tests/theme/wpGetGlobalStylesheet.php

@@ -271 +271 @@
         );
     }
+    /**
+     * Tests that switching themes recalculates the stylesheet.
+     *
+     * @ticket 56970
+     */
+    public function test_switching_themes_should_recalculate_stylesheet() {
+        $stylesheet_for_default_theme = wp_get_global_stylesheet();
+        switch_theme( 'block-theme' );
+        $stylesheet_for_block_theme = wp_get_global_stylesheet();
+        switch_theme( WP_DEFAULT_THEME );
+
+        $this->assertStringNotContainsString( '--wp--preset--font-size--custom: 100px;', $stylesheet_for_default_theme, 'custom font size (100px) not present for default theme' );
+        $this->assertStringContainsString( '--wp--preset--font-size--custom: 100px;', $stylesheet_for_block_theme, 'custom font size (100px) is present for block theme' );
+    }
 }