<?php
/**
* Post revision functions.
*
* @package WordPress
* @subpackage Post_Revisions
*/
/**
* Determines which fields of posts are to be saved in revisions.
*
* @since 2.6.0
* @since 4.5.0 A `WP_Post` object can now be passed to the `$post` parameter.
* @since 4.5.0 The optional `$autosave` parameter was deprecated and renamed to `$deprecated`.
* @access private
*
* @param array|WP_Post $post Optional. A post array or a WP_Post object being processed
* for insertion as a post revision. Default empty array.
* @param bool $deprecated Not used.
* @return string[] Array of fields that can be versioned.
*/
function _wp_post_revision_fields( $post = array(), $deprecated = false ) {
static $fields = null;
if ( ! is_array( $post ) ) {
$post = get_post( $post, ARRAY_A );
}
if ( is_null( $fields ) ) {
// Allow these to be versioned.
$fields = array(
'post_title' => __( 'Title' ),
'post_content' => __( 'Content' ),
'post_excerpt' => __( 'Excerpt' ),
);
}
/**
* Filters the list of fields saved in post revisions.
*
* Included by default: 'post_title', 'post_content' and 'post_excerpt'.
*
* Disallowed fields: 'ID', 'post_name', 'post_parent', 'post_date',
* 'post_date_gmt', 'post_status', 'post_type', 'comment_count',
* and 'post_author'.
*
* @since 2.6.0
* @since 4.5.0 The `$post` parameter was added.
*
* @param string[] $fields List of fields to revision. Contains 'post_title',
* 'post_content', and 'post_excerpt' by default.
* @param array $post A post array being processed for insertion as a post revision.
*/
$fields = apply_filters( '_wp_post_revision_fields', $fields, $post );
// WP uses these internally either in versioning or elsewhere - they cannot be versioned.
foreach ( array( 'ID', 'post_name', 'post_parent', 'post_date', 'post_date_gmt', 'post_status', 'post_type', 'comment_count', 'post_author' ) as $protect ) {
unset( $fields[ $protect ] );
}
return $fields;
}
/**
* Returns a post array ready to be inserted into the posts table as a post revision.
*
* @since 4.5.0
* @access private
*
* @param array|WP_Post $post Optional. A post array or a WP_Post object to be processed
* for insertion as a post revision. Default empty array.
* @param bool $autosave Optional. Is the revision an autosave? Default false.
* @return array Post array ready to be inserted as a post revision.
*/
function _wp_post_revision_data( $post = array(), $autosave = false ) {
if ( ! is_array( $post ) ) {
$post = get_post( $post, ARRAY_A );
}
$fields = _wp_post_revision_fields( $post );
$revision_data = array();
foreach ( array_intersect( array_keys( $post ), array_keys( $fields ) ) as $field ) {
$revision_data[ $field ] = $post[ $field ];
}
$revision_data['post_parent'] = $post['ID'];
$revision_data['post_status'] = 'inherit';
$revision_data['post_type'] = 'revision';
$revision_data['post_name'] = $autosave ? "$post[ID]-autosave-v1" : "$post[ID]-revision-v1"; // "1" is the revisioning system version.
$revision_data['post_date'] = isset( $post['post_modified'] ) ? $post['post_modified'] : '';
$revision_data['post_date_gmt'] = isset( $post['post_modified_gmt'] ) ? $post['post_modified_gmt'] : '';
return $revision_data;
}
/**
* Saves revisions for a post after all changes have been made.
*
* @since 6.4.0
*
* @param int $post_id The post id that was inserted.
* @param WP_Post $post The post object that was inserted.
* @param bool $update Whether this insert is updating an existing post.
*/
function wp_save_post_revision_on_insert( $post_id, $post, $update ) {
if ( ! $update ) {
return;
}
if ( ! has_action( 'post_updated', 'wp_save_post_revision' ) ) {
return;
}
wp_save_post_revision( $post_id );
}
/**
* Creates a revision for the current version of a post.
*
* Typically used immediately after a post update, as every update is a revision,
* and the most recent revision always matches the current post.
*
* @since 2.6.0
*
* @param int $post_id The ID of the post to save as a revision.
* @return int|WP_Error|void Void or 0 if error, new revision ID, if success.
*/
function wp_save_post_revision( $post_id ) {
if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE ) {
return;
}
// Prevent saving post revisions if revisions should be saved on wp_after_insert_post.
if ( doing_action( 'post_updated' ) && has_action( 'wp_after_insert_post', 'wp_save_post_revision_on_insert' ) ) {
return;
}
$post = get_post( $post_id );
if ( ! $post ) {
return;
}
if ( ! post_type_supports( $post->post_type, 'revisions' ) ) {
return;
}
if ( 'auto-draft' === $post->post_status ) {
return;
}
if ( ! wp_revisions_enabled( $post ) ) {
return;
}
/*
* Compare the proposed update with the last stored revision verifying that
* they are different, unless a plugin tells us to always save regardless.
* If no previous revisions, save one.
*/
$revisions = wp_get_post_revisions( $post_id );
if ( $revisions ) {
// Grab the latest revision, but not an autosave.
foreach ( $revisions as $revision ) {
if ( str_contains( $revision->post_name, "{$revision->post_parent}-revision" ) ) {
$latest_revision = $revision;
break;
}
}
/**
* Filters whether the post has changed since the latest revision.
*
* By default a revision is saved only if one of the revisioned fields has changed.
* This filter can override that so a revision is saved even if nothing has changed.
*
* @since 3.6.0
*
* @param bool $check_for_changes Whether to check for changes before saving a new revision.
* Default true.
* @param WP_Post $latest_revision The latest revision post object.
* @param WP_Post $post The post object.
*/
if ( isset( $latest_revision ) && apply_filters( 'wp_save_post_revision_check_for_changes', true, $latest_revision, $post ) ) {
$post_has_changed = false;
foreach ( array_keys( _wp_post_revision_fields( $post ) ) as $field ) {
if ( normalize_whitespace( $post->$field ) !== normalize_whitespace( $latest_revision->$field ) ) {
$post_has_changed = true;
break;
}
}
/**
* Filters whether a post has changed.
*
* By default a revision is saved only if one of the revisioned fields has changed.
* This filter allows for additional checks to determine if there were changes.
*
* @since 4.1.0
*
* @param bool $post_has_changed Whether the post has changed.
* @param WP_Post $latest_revision The latest revision post object.
* @param WP_Post $post The post object.
*/
$post_has_changed = (bool) apply_filters( 'wp_save_post_revision_post_has_changed', $post_has_changed, $latest_revision, $post );
// Don't save revision if post unchanged.
if ( ! $post_has_changed ) {
return;
}
}
}
$return = _wp_put_post_revision( $post );
/*
* If a limit for the number of revisions to keep has been set,
* delete the oldest ones.
*/
$revisions_to_keep = wp_revisions_to_keep( $post );
if ( $revisions_to_keep < 0 ) {
return $return;
}
$revisions = wp_get_post_revisions( $post_id, array( 'order' => 'ASC' ) );
/**
* Filters the revisions to be considered for deletion.
*
* @since 6.2.0
*
* @param WP_Post[] $revisions Array of revisions, or an empty array if none.
* @param int $post_id The ID of the post to save as a revision.
*/
$revisions = apply_filters(
'wp_save_post_revision_revisions_before_deletion',
$revisions,
$post_id
);
$delete = count( $revisions ) - $revisions_to_keep;
if ( $delete < 1 ) {
return $return;
}
$revisions = array_slice( $revisions, 0, $delete );
for ( $i = 0; isset( $revisions[ $i ] ); $i++ ) {
if ( str_contains( $revisions[ $i ]->post_name, 'autosave' ) ) {
continue;
}
wp_delete_post_revision( $revisions[ $i ]->ID );
}
return $return;
}
/**
* Retrieves the autosaved data of the specified post.
*
* Returns a post object w