Changeset 55085

Timestamp:

01/18/2023 11:18:36 AM (2 years ago)

Author:

spacedmonkey

Message:

Posts, Post Types: Use persistent caching in get_adjacent_post function.

The function get_adjacent_post cached the results of database query in the cache group counts. This is a none persistent group and meant cache would not persist on the next request. Change cache to save to the posts cache group. Cache invalidation is done by using get last changed value of the posts and terms group as a salt for the cache key.

Props spacedmonkey, peterwilsoncc, johnbillion, boonebgorges, mukesh27, dd32.
Fixes #41131.

Location:

trunk

Files:

• src/wp-includes/link-template.php (modified) (2 diffs)
• tests/phpunit/tests/link/getAdjacentPost.php (modified) (1 diff)

trunk/src/wp-includes/link-template.php

@@ -1977 +1977 @@
     $sort = apply_filters( "get_{$adjacent}_post_sort", "ORDER BY p.post_date $order LIMIT 1", $post, $order );
 
-    $query     = "SELECT p.ID FROM $wpdb->posts AS p $join $where $sort";
-    $query_key = 'adjacent_post_' . md5( $query );
-    $result    = wp_cache_get( $query_key, 'counts' );
+    $query        = "SELECT p.ID FROM $wpdb->posts AS p $join $where $sort";
+    $key          = md5( $query );
+    $last_changed = wp_cache_get_last_changed( 'posts' );
+    if ( $in_same_term || ! empty( $excluded_terms ) ) {
+        $last_changed .= wp_cache_get_last_changed( 'terms' );
+    }
+    $cache_key = "adjacent_post:$key:$last_changed";
+
+    $result = wp_cache_get( $cache_key, 'posts' );
     if ( false !== $result ) {
         if ( $result ) {
@@ -1992 +1998 @@
     }
 
-    wp_cache_set( $query_key, $result, 'counts' );
+    wp_cache_set( $cache_key, $result, 'posts' );
 
     if ( $result ) {

trunk/tests/phpunit/tests/link/getAdjacentPost.php

@@ -351 +351 @@
         return $excluded_terms;
     }
+
+    /**
+     * @ticket 41131
+     */
+    public function test_get_adjacent_post_cache() {
+        // Need some sample posts to test adjacency.
+        $post_one = self::factory()->post->create_and_get(
+            array(
+                'post_title' => 'First',
+                'post_date'  => '2012-01-01 12:00:00',
+            )
+        );
+
+        $post_two = self::factory()->post->create_and_get(
+            array(
+                'post_title' => 'Second',
+                'post_date'  => '2012-02-01 12:00:00',
+            )
+        );
+
+        $post_three = self::factory()->post->create_and_get(
+            array(
+                'post_title' => 'Third',
+                'post_date'  => '2012-03-01 12:00:00',
+            )
+        );
+
+        $post_four = self::factory()->post->create_and_get(
+            array(
+                'post_title' => 'Fourth',
+                'post_date'  => '2012-04-01 12:00:00',
+            )
+        );
+
+        // Assign some terms.
+        wp_set_object_terms( $post_one->ID, 'WordPress', 'category', false );
+        wp_set_object_terms( $post_three->ID, 'WordPress', 'category', false );
+
+        wp_set_object_terms( $post_two->ID, 'plugins', 'post_tag', false );
+        wp_set_object_terms( $post_four->ID, 'plugins', 'post_tag', false );
+
+        // Test normal post adjacency.
+        $this->go_to( get_permalink( $post_two->ID ) );
+
+        // Test getting the right result.
+        $first_run = get_adjacent_post( false, '', true );
+        $this->assertEquals( $post_one, $first_run, 'Did not get first post when on second post' );
+        $this->assertNotEquals( $post_two, $first_run, 'Got second post when on second post' );
+
+        // Query count to test caching.
+        $num_queries = get_num_queries();
+        $second_run  = get_adjacent_post( false, '', true );
+        $this->assertNotEquals( $post_two, $second_run, 'Got second post when on second post on second run' );
+        $this->assertEquals( $post_one, $second_run, 'Did not get first post when on second post on second run' );
+        $this->assertSame( $num_queries, get_num_queries() );
+
+        // Test creating new post busts cache.
+        $post_five   = self::factory()->post->create_and_get(
+            array(
+                'post_title' => 'Five',
+                'post_date'  => '2012-04-01 12:00:00',
+            )
+        );
+        $num_queries = get_num_queries();
+
+        $this->assertEquals( $post_one, get_adjacent_post( false, '', true ), 'Did not get first post after new post is added' );
+        $this->assertSame( get_num_queries() - $num_queries, 1, 'Number of queries run was not one after new post is added' );
+
+        $this->assertEquals( $post_four, get_adjacent_post( true, '', false ), 'Did not get forth post after new post is added' );
+        $num_queries = get_num_queries();
+        $this->assertEquals( $post_four, get_adjacent_post( true, '', false ), 'Did not get forth post after new post is added' );
+        $this->assertSame( $num_queries, get_num_queries() );
+        wp_set_object_terms( $post_four->ID, 'themes', 'post_tag', false );
+
+        $num_queries = get_num_queries();
+        $this->assertEquals( $post_four, get_adjacent_post( true, '', false ), 'Result of function call is wrong after after adding new term' );
+        $this->assertSame( get_num_queries() - $num_queries, 2, 'Number of queries run was not two after adding new term' );
+    }
 }