Changeset 7806

Timestamp:

10/31/2018 03:02:42 AM (6 years ago)

Author:

dd32

Message:

Support Forums: Disable canonical on 404 requests when a short name query var is provided.

This is to avoid some expensive database queries which causes out-of-memory fatal errors on the Support Forum.

Fixes #3894.

File:

• sites/trunk/wordpress.org/public_html/wp-content/plugins/support-forums/inc/class-performance-optimizations.php (modified) (1 diff)

sites/trunk/wordpress.org/public_html/wp-content/plugins/support-forums/inc/class-performance-optimizations.php

@@ -39 +39 @@
         // Disable post meta key lookup, see https://core.trac.wordpress.org/ticket/33885.
         add_filter( 'postmeta_form_keys', '__return_empty_array' );
+
+        // Disable canonical redirects for short post_names
+        add_filter( 'template_redirect', array( $this, 'maybe_disable_404_canonical' ), 9 );
+
+    }
+
+    /**
+     * Disables Canonical redirects on 404 pages when a short (<5char) name is provided.
+     *
+     * This is used to avoid really bad queries in redirect_guess_404_permalink() on urls such as:
+     * https://wordpress.org/support/topic/test/*1*
+     */
+    public function maybe_disable_404_canonical() {
+        if ( is_404() && get_query_var( 'name' ) && strlen( get_query_var( 'name' ) ) < 5 ) {
+            remove_filter( 'template_redirect', 'redirect_canonical' );
+        }
     }