3 * Post revision functions.
6 * @subpackage Post_Revisions
10 * Determines which fields of posts are to be saved in revisions.
12 * Does two things. If passed a post *array*, it will return a post array ready
13 * to be inserted into the posts table as a post revision. Otherwise, returns
14 * an array whose keys are the post fields to be saved for post revisions.
19 * @staticvar array $fields
21 * @param array|null $post Optional. A post array to be processed for insertion as a post revision. Default null.
22 * @param bool $autosave Optional. Is the revision an autosave? Default false.
23 * @return array Post array ready to be inserted as a post revision or array of fields that can be versioned.
25 function _wp_post_revision_fields( $post = null, $autosave = false ) {
26 static $fields = null;
28 if ( is_null( $fields ) ) {
29 // Allow these to be versioned
31 'post_title' => __( 'Title' ),
32 'post_content' => __( 'Content' ),
33 'post_excerpt' => __( 'Excerpt' ),
37 * Filter the list of fields saved in post revisions.
39 * Included by default: 'post_title', 'post_content' and 'post_excerpt'.
41 * Disallowed fields: 'ID', 'post_name', 'post_parent', 'post_date',
42 * 'post_date_gmt', 'post_status', 'post_type', 'comment_count',
47 * @param array $fields List of fields to revision. Contains 'post_title',
48 * 'post_content', and 'post_excerpt' by default.
50 $fields = apply_filters( '_wp_post_revision_fields', $fields );
52 // WP uses these internally either in versioning or elsewhere - they cannot be versioned
53 foreach ( array( 'ID', 'post_name', 'post_parent', 'post_date', 'post_date_gmt', 'post_status', 'post_type', 'comment_count', 'post_author' ) as $protect )
54 unset( $fields[$protect] );
57 if ( !is_array($post) )
61 foreach ( array_intersect( array_keys( $post ), array_keys( $fields ) ) as $field )
62 $return[$field] = $post[$field];
64 $return['post_parent'] = $post['ID'];
65 $return['post_status'] = 'inherit';
66 $return['post_type'] = 'revision';
67 $return['post_name'] = $autosave ? "$post[ID]-autosave-v1" : "$post[ID]-revision-v1"; // "1" is the revisioning system version
68 $return['post_date'] = isset($post['post_modified']) ? $post['post_modified'] : '';
69 $return['post_date_gmt'] = isset($post['post_modified_gmt']) ? $post['post_modified_gmt'] : '';
75 * Creates a revision for the current version of a post.
77 * Typically used immediately after a post update, as every update is a revision,
78 * and the most recent revision always matches the current post.
82 * @param int $post_id The ID of the post to save as a revision.
83 * @return int|WP_Error|void Void or 0 if error, new revision ID, if success.
85 function wp_save_post_revision( $post_id ) {
86 if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE )
89 if ( ! $post = get_post( $post_id ) )
92 if ( ! post_type_supports( $post->post_type, 'revisions' ) )
95 if ( 'auto-draft' == $post->post_status )
98 if ( ! wp_revisions_enabled( $post ) )
101 // Compare the proposed update with the last stored revision verifying that
102 // they are different, unless a plugin tells us to always save regardless.
103 // If no previous revisions, save one
104 if ( $revisions = wp_get_post_revisions( $post_id ) ) {
105 // grab the last revision, but not an autosave
106 foreach ( $revisions as $revision ) {
107 if ( false !== strpos( $revision->post_name, "{$revision->post_parent}-revision" ) ) {
108 $last_revision = $revision;
114 * Filter whether the post has changed since the last revision.
116 * By default a revision is saved only if one of the revisioned fields has changed.
117 * This filter can override that so a revision is saved even if nothing has changed.
121 * @param bool $check_for_changes Whether to check for changes before saving a new revision.
123 * @param WP_Post $last_revision The the last revision post object.
124 * @param WP_Post $post The post object.
127 if ( isset( $last_revision ) && apply_filters( 'wp_save_post_revision_check_for_changes', $check_for_changes = true, $last_revision, $post ) ) {
128 $post_has_changed = false;
130 foreach ( array_keys( _wp_post_revision_fields() ) as $field ) {
131 if ( normalize_whitespace( $post->$field ) != normalize_whitespace( $last_revision->$field ) ) {
132 $post_has_changed = true;
138 * Filter whether a post has changed.
140 * By default a revision is saved only if one of the revisioned fields has changed.
141 * This filter allows for additional checks to determine if there were changes.
145 * @param bool $post_has_changed Whether the post has changed.
146 * @param WP_Post $last_revision The last revision post object.
147 * @param WP_Post $post The post object.
150 $post_has_changed = (bool) apply_filters( 'wp_save_post_revision_post_has_changed', $post_has_changed, $last_revision, $post );
152 //don't save revision if post unchanged
153 if ( ! $post_has_changed ) {
159 $return = _wp_put_post_revision( $post );
161 // If a limit for the number of revisions to keep has been set,
162 // delete the oldest ones.
163 $revisions_to_keep = wp_revisions_to_keep( $post );
165 if ( $revisions_to_keep < 0 )
168 $revisions = wp_get_post_revisions( $post_id, array( 'order' => 'ASC' ) );
170 $delete = count($revisions) - $revisions_to_keep;
175 $revisions = array_slice( $revisions, 0, $delete );
177 for ( $i = 0; isset( $revisions[$i] ); $i++ ) {
178 if ( false !== strpos( $revisions[ $i ]->post_name, 'autosave' ) )
181 wp_delete_post_revision( $revisions[ $i ]->ID );
188 * Retrieve the autosaved data of the specified post.
190 * Returns a post object containing the information that was autosaved for the
191 * specified post. If the optional $user_id is passed, returns the autosave for that user
192 * otherwise returns the latest autosave.
196 * @param int $post_id The post ID.
197 * @param int $user_id Optional The post author ID.
198 * @return WP_Post|false The autosaved data or false on failure or when no autosave exists.
200 function wp_get_post_autosave( $post_id, $user_id = 0 ) {
201 $revisions = wp_get_post_revisions( $post_id, array( 'check_enabled' => false ) );
203 foreach ( $revisions as $revision ) {
204 if ( false !== strpos( $revision->post_name, "{$post_id}-autosave" ) ) {
205 if ( $user_id && $user_id != $revision->post_author )
216 * Determines if the specified post is a revision.
220 * @param int|WP_Post $post Post ID or post object.
221 * @return false|int False if not a revision, ID of revision's parent otherwise.
223 function wp_is_post_revision( $post ) {
224 if ( !$post = wp_get_post_revision( $post ) )
227 return (int) $post->post_parent;
231 * Determines if the specified post is an autosave.
235 * @param int|WP_Post $post Post ID or post object.
236 * @return false|int False if not a revision, ID of autosave's parent otherwise
238 function wp_is_post_autosave( $post ) {
239 if ( !$post = wp_get_post_revision( $post ) )
242 if ( false !== strpos( $post->post_name, "{$post->post_parent}-autosave" ) )
243 return (int) $post->post_parent;
249 * Inserts post data into the posts table as a post revision.
254 * @param int|WP_Post|array|null $post Post ID, post object OR post array.
255 * @param bool $autosave Optional. Is the revision an autosave?
256 * @return int|WP_Error WP_Error or 0 if error, new revision ID if success.
258 function _wp_put_post_revision( $post = null, $autosave = false ) {
259 if ( is_object($post) )
260 $post = get_object_vars( $post );
261 elseif ( !is_array($post) )
262 $post = get_post($post, ARRAY_A);
264 if ( ! $post || empty($post['ID']) )
265 return new WP_Error( 'invalid_post', __( 'Invalid post ID.' ) );
267 if ( isset($post['post_type']) && 'revision' == $post['post_type'] )
268 return new WP_Error( 'post_type', __( 'Cannot create a revision of a revision' ) );
270 $post = _wp_post_revision_fields( $post, $autosave );
271 $post = wp_slash($post); //since data is from db
273 $revision_id = wp_insert_post( $post );
274 if ( is_wp_error($revision_id) )
277 if ( $revision_id ) {
279 * Fires once a revision has been saved.
283 * @param int $revision_id Post revision ID.
285 do_action( '_wp_put_post_revision', $revision_id );
292 * Gets a post revision.
296 * @param int|WP_Post $post The post ID or object.
297 * @param string $output Optional. OBJECT, ARRAY_A, or ARRAY_N.
298 * @param string $filter Optional sanitation filter. @see sanitize_post().
299 * @return WP_Post|array|null Null if error or post object if success.
301 function wp_get_post_revision(&$post, $output = OBJECT, $filter = 'raw') {
302 if ( !$revision = get_post( $post, OBJECT, $filter ) )
304 if ( 'revision' !== $revision->post_type )
307 if ( $output == OBJECT ) {
309 } elseif ( $output == ARRAY_A ) {
310 $_revision = get_object_vars($revision);
312 } elseif ( $output == ARRAY_N ) {
313 $_revision = array_values(get_object_vars($revision));
321 * Restores a post to the specified revision.
323 * Can restore a past revision using all fields of the post revision, or only selected fields.
327 * @param int|WP_Post $revision_id Revision ID or revision object.
328 * @param array $fields Optional. What fields to restore from. Defaults to all.
329 * @return int|false|null Null if error, false if no fields to restore, (int) post ID if success.
331 function wp_restore_post_revision( $revision_id, $fields = null ) {
332 if ( !$revision = wp_get_post_revision( $revision_id, ARRAY_A ) )
335 if ( !is_array( $fields ) )
336 $fields = array_keys( _wp_post_revision_fields() );
339 foreach ( array_intersect( array_keys( $revision ), $fields ) as $field ) {
340 $update[$field] = $revision[$field];
346 $update['ID'] = $revision['post_parent'];
348 $update = wp_slash( $update ); //since data is from db
350 $post_id = wp_update_post( $update );
351 if ( ! $post_id || is_wp_error( $post_id ) )
354 // Add restore from details
355 $restore_details = array(
356 'restored_revision_id' => $revision_id,
357 'restored_by_user' => get_current_user_id(),
358 'restored_time' => time()
360 update_post_meta( $post_id, '_post_restored_from', $restore_details );
362 // Update last edit user
363 update_post_meta( $post_id, '_edit_last', get_current_user_id() );
366 * Fires after a post revision has been restored.
370 * @param int $post_id Post ID.
371 * @param int $revision_id Post revision ID.
373 do_action( 'wp_restore_post_revision', $post_id, $revision['ID'] );
379 * Deletes a revision.
381 * Deletes the row from the posts table corresponding to the specified revision.
385 * @param int|WP_Post $revision_id Revision ID or revision object.
386 * @return array|false|WP_Post|WP_Error|null Null or WP_Error if error, deleted post if success.
388 function wp_delete_post_revision( $revision_id ) {
389 if ( ! $revision = wp_get_post_revision( $revision_id ) ) {
393 $delete = wp_delete_post( $revision->ID );
396 * Fires once a post revision has been deleted.
400 * @param int $revision_id Post revision ID.
401 * @param object|array $revision Post revision object or array.
403 do_action( 'wp_delete_post_revision', $revision->ID, $revision );
410 * Returns all revisions of specified post.
414 * @param int|WP_Post $post_id Optional. Post ID or WP_Post object. Default is global $post.
415 * @return array An array of revisions, or an empty array if none.
417 function wp_get_post_revisions( $post_id = 0, $args = null ) {
418 $post = get_post( $post_id );
419 if ( ! $post || empty( $post->ID ) )
422 $defaults = array( 'order' => 'DESC', 'orderby' => 'date ID', 'check_enabled' => true );
423 $args = wp_parse_args( $args, $defaults );
425 if ( $args['check_enabled'] && ! wp_revisions_enabled( $post ) )
428 $args = array_merge( $args, array( 'post_parent' => $post->ID, 'post_type' => 'revision', 'post_status' => 'inherit' ) );
430 if ( ! $revisions = get_children( $args ) )
437 * Determine if revisions are enabled for a given post.
441 * @param WP_Post $post The post object.
442 * @return bool True if number of revisions to keep isn't zero, false otherwise.
444 function wp_revisions_enabled( $post ) {
445 return wp_revisions_to_keep( $post ) !== 0;
449 * Determine how many revisions to retain for a given post.
451 * By default, an infinite number of revisions are kept.
453 * The constant WP_POST_REVISIONS can be set in wp-config to specify the limit
454 * of revisions to keep.
458 * @param WP_Post $post The post object.
459 * @return int The number of revisions to keep.
461 function wp_revisions_to_keep( $post ) {
462 $num = WP_POST_REVISIONS;
467 $num = intval( $num );
469 if ( ! post_type_supports( $post->post_type, 'revisions' ) )
473 * Filter the number of revisions to save for the given post.
475 * Overrides the value of WP_POST_REVISIONS.
479 * @param int $num Number of revisions to store.
480 * @param WP_Post $post Post object.
482 return (int) apply_filters( 'wp_revisions_to_keep', $num, $post );
486 * Sets up the post object for preview based on the post autosave.
491 * @param WP_Post $post
492 * @return WP_Post|false
494 function _set_preview( $post ) {
495 if ( ! is_object( $post ) ) {
499 $preview = wp_get_post_autosave( $post->ID );
500 if ( ! is_object( $preview ) ) {
504 $preview = sanitize_post( $preview );
506 $post->post_content = $preview->post_content;
507 $post->post_title = $preview->post_title;
508 $post->post_excerpt = $preview->post_excerpt;
510 add_filter( 'get_the_terms', '_wp_preview_terms_filter', 10, 3 );
516 * Filters the latest content for preview from the post autosave.
521 function _show_post_preview() {
522 if ( isset($_GET['preview_id']) && isset($_GET['preview_nonce']) ) {
523 $id = (int) $_GET['preview_id'];
525 if ( false === wp_verify_nonce( $_GET['preview_nonce'], 'post_preview_' . $id ) )
526 wp_die( __('You do not have permission to preview drafts.') );
528 add_filter('the_preview', '_set_preview');
533 * Filters terms lookup to set the post format.
538 * @param array $terms
539 * @param int $post_id
540 * @param string $taxonomy
543 function _wp_preview_terms_filter( $terms, $post_id, $taxonomy ) {
544 if ( ! $post = get_post() )
547 if ( empty( $_REQUEST['post_format'] ) || $post->ID != $post_id || 'post_format' != $taxonomy || 'revision' == $post->post_type )
550 if ( 'standard' == $_REQUEST['post_format'] )
552 elseif ( $term = get_term_by( 'slug', 'post-format-' . sanitize_key( $_REQUEST['post_format'] ), 'post_format' ) )
553 $terms = array( $term ); // Can only have one post format
559 * Gets the post revision version.
564 * @param WP_Post $revision
567 function _wp_get_post_revision_version( $revision ) {
568 if ( is_object( $revision ) )
569 $revision = get_object_vars( $revision );
570 elseif ( !is_array( $revision ) )
573 if ( preg_match( '/^\d+-(?:autosave|revision)-v(\d+)$/', $revision['post_name'], $matches ) )
574 return (int) $matches[1];
580 * Upgrade the revisions author, add the current post as a revision and set the revisions version to 1
585 * @global wpdb $wpdb WordPress database abstraction object.
587 * @param WP_Post $post Post object
588 * @param array $revisions Current revisions of the post
589 * @return bool true if the revisions were upgraded, false if problems
591 function _wp_upgrade_revisions_of_post( $post, $revisions ) {
594 // Add post option exclusively
595 $lock = "revision-upgrade-{$post->ID}";
597 $result = $wpdb->query( $wpdb->prepare( "INSERT IGNORE INTO `$wpdb->options` (`option_name`, `option_value`, `autoload`) VALUES (%s, %s, 'no') /* LOCK */", $lock, $now ) );
599 // If we couldn't get a lock, see how old the previous lock is
600 $locked = get_option( $lock );
602 // Can't write to the lock, and can't read the lock.
603 // Something broken has happened
607 if ( $locked > $now - 3600 ) {
608 // Lock is not too old: some other process may be upgrading this post. Bail.
612 // Lock is too old - update it (below) and continue
615 // If we could get a lock, re-"add" the option to fire all the correct filters.
616 update_option( $lock, $now );
622 $this_revision = current( $revisions );
623 $prev_revision = next( $revisions );
625 $this_revision_version = _wp_get_post_revision_version( $this_revision );
627 // Something terrible happened
628 if ( false === $this_revision_version )
631 // 1 is the latest revision version, so we're already up to date.
632 // No need to add a copy of the post as latest revision.
633 if ( 0 < $this_revision_version ) {
638 // Always update the revision version
640 'post_name' => preg_replace( '/^(\d+-(?:autosave|revision))[\d-]*$/', '$1-v1', $this_revision->post_name ),
643 // If this revision is the oldest revision of the post, i.e. no $prev_revision,
644 // the correct post_author is probably $post->post_author, but that's only a good guess.
645 // Update the revision version only and Leave the author as-is.
646 if ( $prev_revision ) {
647 $prev_revision_version = _wp_get_post_revision_version( $prev_revision );
649 // If the previous revision is already up to date, it no longer has the information we need :(
650 if ( $prev_revision_version < 1 )
651 $update['post_author'] = $prev_revision->post_author;
654 // Upgrade this revision
655 $result = $wpdb->update( $wpdb->posts, $update, array( 'ID' => $this_revision->ID ) );
658 wp_cache_delete( $this_revision->ID, 'posts' );
660 } while ( $prev_revision );
662 delete_option( $lock );
664 // Add a copy of the post as latest revision.
666 wp_save_post_revision( $post->ID );