Changeset 38925 for trunk/src/wp-includes/class-wp.php

Timestamp:

10/25/2016 08:47:06 PM (8 years ago)

Author:

rachelbaker

Message:

Feeds: Always return a valid timestamp for the Last-Modified header of comment or post feeds.

Fixes bug where an invalid Last-Modified value would be returned in feed requests for sites that had 0 items to return. Comment or post feeds will now return the current timestamp as the Last-Modified header value. Example: a request for the comments feed for a site without any comments.

Replaced use of the local static variable $cache_lastcommentmodified to store the modified date in get_lastcommentmodified() with the Object Cache API. The get_lastcommentmodified() function returns early if there is a cached value and returns false if there where no comments found. Introduced _clear_modified_cache_on_transition_comment_status() to flush the lastcommentmodified cache key when a comment enters or leaves approval status. In get_lastpostmodified() return early if there is a cached value and return false if there are no posts found.

Props swissspidy, rachelbaker, dllh, leobaiano.
Fixes #38027.

File:

• trunk/src/wp-includes/class-wp.php (modified) (1 diff)

trunk/src/wp-includes/class-wp.php

@@ -423 +423 @@
             $headers['Content-Type'] = feed_content_type( $type ) . '; charset=' . get_option( 'blog_charset' );
 
-            // We're showing a feed, so WP is indeed the only thing that last changed
-            if ( !empty($this->query_vars['withcomments'])
-                || false !== strpos( $this->query_vars['feed'], 'comments-' )
-                || ( empty($this->query_vars['withoutcomments'])
-                    && ( !empty($this->query_vars['p'])
-                        || !empty($this->query_vars['name'])
-                        || !empty($this->query_vars['page_id'])
-                        || !empty($this->query_vars['pagename'])
-                        || !empty($this->query_vars['attachment'])
-                        || !empty($this->query_vars['attachment_id'])
-                    )
-                )
-            )
-                $wp_last_modified = mysql2date('D, d M Y H:i:s', get_lastcommentmodified('GMT'), 0).' GMT';
-            else
-                $wp_last_modified = mysql2date('D, d M Y H:i:s', get_lastpostmodified('GMT'), 0).' GMT';
+            // We're showing a feed, so WP is indeed the only thing that last changed.
+            if ( ! empty( $this->query_vars['withcomments'] )
+                 || false !== strpos( $this->query_vars['feed'], 'comments-' )
+                 || ( empty( $this->query_vars['withoutcomments'] )
+                      && ( ! empty( $this->query_vars['p'] )
+                           || ! empty( $this->query_vars['name'] )
+                           || ! empty( $this->query_vars['page_id'] )
+                           || ! empty( $this->query_vars['pagename'] )
+                           || ! empty( $this->query_vars['attachment'] )
+                           || ! empty( $this->query_vars['attachment_id'] )
+                      )
+                 )
+            ) {
+                $wp_last_modified = mysql2date( 'D, d M Y H:i:s', get_lastcommentmodified( 'GMT' ), false );
+            } else {
+                $wp_last_modified = mysql2date( 'D, d M Y H:i:s', get_lastpostmodified( 'GMT' ), false );
+            }
+
+            if ( ! $wp_last_modified ) {
+                $wp_last_modified = date( 'D, d M Y H:i:s' );
+            }
+
+            $wp_last_modified .= ' GMT';
+
             $wp_etag = '"' . md5($wp_last_modified) . '"';
             $headers['Last-Modified'] = $wp_last_modified;