Changeset 23823 for trunk/wp-includes/revision.php

Timestamp:

03/27/2013 08:21:38 PM (12 years ago)

Author:

markjaquith

Message:

Fix a longstanding "off by one" revision authorship bug.

• Fixes old revision data on the fly when you open a post for editing.
• Uses post_name of revisions to store a post version number (-v1), so we know what has been fixed.
• Latest version should also have a revision stored, whereas before it did not.

props adamsilverstein, mdawaffe. fixes #16215.

File:

• trunk/wp-includes/revision.php (modified) (6 diffs)

trunk/wp-includes/revision.php

@@ -53 +53 @@
     $return['post_status']   = 'inherit';
     $return['post_type']     = 'revision';
-    $return['post_name']     = $autosave ? "$post[ID]-autosave" : "$post[ID]-revision";
+    $return['post_name']     = $autosave ? "$post[ID]-autosave-v1" : "$post[ID]-revision-v1"; // "1" is the revisioning system version
     $return['post_date']     = isset($post['post_modified']) ? $post['post_modified'] : '';
     $return['post_date_gmt'] = isset($post['post_modified_gmt']) ? $post['post_modified_gmt'] : '';
+    $return['post_author']   = get_post_meta( $post['ID'], '_edit_last', true );
 
     return $return;
@@ -63 +64 @@
  * Saves an already existing post as a post revision.
  *
- * Typically used immediately prior to post updates.
+ * Typically used immediately prior and after post updates.
+ * Prior to update checks for old revision data (latest revision != current post before update) and adds a copy of the current post as a revision if missing
+ * After update adds a copy of the current post as a revision, so latest revision always matches current post
  *
  * @package WordPress
@@ -70 +73 @@
  *
  * @uses _wp_put_post_revision()
+ * @uses wp_first_revision_matches_current_version()
  *
  * @param int $post_id The ID of the post to save as a revision.
  * @return mixed Null or 0 if error, new revision ID, if success.
  */
-function wp_save_post_revision( $post_id, $new_data = null ) {
-    // We do autosaves manually with wp_create_post_autosave()
+function wp_save_post_revision( $post_id ) {
+    //check to see if the post's first revision already matches the post data
+    //should be true before post update, _except_ for old data which
+    //doesn't include a copy of the current post data in revisions
+    if ( wp_first_revision_matches_current_version( $post_id ) )
+        return;
+
     if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE )
         return;
@@ -91 +100 @@
         return;
 
-    // if new data is supplied, check that it is different from last saved revision, unless a plugin tells us to always save regardless
-    if ( apply_filters( 'wp_save_post_revision_check_for_changes', true, $post, $new_data ) && is_array( $new_data ) ) {
-        $post_has_changed = false;
-        foreach ( array_keys( _wp_post_revision_fields() ) as $field ) {
-            if ( normalize_whitespace( $new_data[ $field ] ) != normalize_whitespace( $post[ $field ] ) ) {
-                $post_has_changed = true;
-                break;
+    // compare the proposed update with the last stored revision, verify
+    // different, unless a plugin tells us to always save regardless
+    if ( $revisions = wp_get_post_revisions( $post_id ) ) {
+        // grab the last revision
+        $last_revision = array_shift( $revisions );
+
+        //if no previous revisions, save one for sure
+        if ( $last_revision_array = get_post( $last_revision->ID, ARRAY_A ) ) {
+
+            if ( apply_filters( 'wp_save_post_revision_check_for_changes', true, $last_revision_array, $post ) && is_array( $post ) ) {
+                $post_has_changed = false;
+
+                foreach ( array_keys( _wp_post_revision_fields() ) as $field ) {
+
+                    if ( normalize_whitespace( $post[ $field ] ) != normalize_whitespace( $last_revision_array[ $field ] ) ) {
+                        $post_has_changed = true;
+                        break;
+
+                    }
+                }
+
+                //don't save revision if post unchanged
+                if( ! $post_has_changed )
+                    return;
             }
         }
-        //don't save revision if post unchanged
-        if( ! $post_has_changed )
-            return;
     }
 
@@ -123 +146 @@
 
     for ( $i = 0; isset($revisions[$i]); $i++ ) {
-        if ( false !== strpos( $revisions[$i]->post_name, 'autosave' ) )
+        if ( false !== strpos( $revisions[ $i ]->post_name, 'autosave' ) )
             continue;
-        wp_delete_post_revision( $revisions[$i]->ID );
+        wp_delete_post_revision( $revisions[ $i ]->ID );
     }
 
@@ -441 +464 @@
     return $post;
 }
+
+function _wp_get_post_revision_version( $post ) {
+    if ( is_array( $post ) ) {
+        if ( ! isset( $post['post_name'] ) ) {
+            return false;
+        }
+
+        $name = $post['post_name'];
+    } elseif ( is_object( $post ) ) {
+        if ( ! isset( $post->post_name ) ) {
+            return false;
+        }
+
+        $name = $post->post_name;
+    } else {
+        return false;
+    }
+
+    if ( ! preg_match( '/^(\d+-)(?:autosave|revision)(?:-v)(\d+)$/', $name, $matches ) ) {
+        return 0;
+    }
+
+    if ( '1' === $matches[2] ) {
+        return 1;
+    }
+
+    return 0;
+}
+
+/**
+ * Upgrade the data
+ *
+ * @package WordPress
+ * @subpackage Post_Revisions
+ * @since 3.6.0
+ *
+ * @uses get_post()
+ * @uses post_type_supports()
+ * @uses wp_get_post_revisions()
+ * @uses wp_save_post_revision()
+ *
+ * @param int|object $post_id Post ID or post object
+ * @return true if success, false if problems
+ */
+function _wp_upgrade_revisions_of_post( $post ) {
+    global $wpdb;
+
+    $post = get_post( $post );
+    if ( ! $post )
+        return false;
+
+    //make sure we have a current revision, only adds one if missing
+    wp_save_post_revision( $post->ID );
+
+    if ( ! post_type_supports( $post->post_type, 'revisions' ) )
+        return false;
+
+    $revisions = wp_get_post_revisions( $post->ID ); // array( 'order' => 'DESC', 'orderby' => 'date' ); // Always work from most recent to oldest
+
+
+    if ( ! $revisions )
+        return true;
+
+    // Add post option exclusively
+    $lock      = "revision-upgrade-{$post->ID}";
+    $locked_at = number_format( microtime( true ), 10, '.', '' );
+    $result = $wpdb->query( $wpdb->prepare( "INSERT IGNORE INTO `$wpdb->options` (`option_name`, `option_value`, `autoload`) VALUES (%s, %s, 'no') /* LOCK */", $lock, $locked_at ) );
+    if ( ! $result ) {
+        // If we couldn't get a lock, see how old the previous lock is
+        $locked_at = get_option( $lock );
+        if ( !$locked_at ) {
+            // Can't write to the lock, and can't read the lock.
+            // Something broken has happened
+            return false;
+        }
+
+        if ( $lock_at < number_format( microtime( true ), 10, '.', '' ) - 3600 ) {
+            // Lock is too old - try again
+            delete_option( $lock );
+            return wp_upgrade_revisions_of_post( $post );
+        }
+
+        // Lock is not too old: some other process may be upgrading this post.  Bail.
+        return;
+    } else {
+        // If we could get a lock, re-"add" the option to fire all the correct filters.
+        add_option( $lock, $locked_at );
+    }
+
+    $success = true;
+
+    reset( $revisions );
+    do {
+        $this_revision = current( $revisions );
+        $prev_revision = next( $revisions );
+
+        $this_revision_version = _wp_get_post_revision_version( $this_revision );
+
+        error_log($this_revision_version);
+
+        // Something terrible happened
+        if ( false === $this_revision_version )
+            continue;
+
+        // 1 is the latest revision version, so we're already up to date
+        if ( 0 < $this_revision_version )
+            continue;
+
+        // This revision is the oldest revision of the post.
+        // The correct post_author is probably $post->post_author, but that's only a good guess.
+        // Leave un-upgraded.
+        if ( ! $prev_revision ) {
+            continue;
+        }
+
+        $prev_revision_version = _wp_get_post_revision_version( $prev_revision );
+
+        // If the previous revision is already up to date, it no longer has the information we need :(
+        if ( 0 < $prev_revision_version ) {
+            continue;
+        }
+
+        // Upgrade this revision
+        // Cast as object so that wp_update_post() handles slashing for us
+        $update = (object) array(
+            'ID'          => $this_revision->ID,
+            'post_name'   => preg_replace( '/^(\d+-)(autosave|revision)-(\d+)$/', '$1$2-v1', $this_revision->post_name ),
+            'post_author' => $prev_revision->post_author,
+        );
+        //error_log(json_encode($update));
+        $result = wp_update_post( $update );
+        if ( ! $result || is_wp_error( $result ) ) {
+            // Wilhelm!
+            $success = false;
+            break;
+        }
+    } while ( $prev_revision );
+
+    delete_option( $lock );
+    return true;
+}
+
 
 function _show_post_preview() {