Force a Post to Draft on Save

Force a post to draft if specific meta is invalid (or other reason), in this case the start and end date/time.

	<?php
	/**
	* For a post to draft if specific meta is invalid, in this case the start and end date/time.
	*
	* @author Joshua David Nelson, [email protected]
	*/
	add_action( 'updated_post_meta', 'jdn_force_draft', 10, 2 );
	function jdn_force_draft( $meta_id, $post_id ) {
	if( get_post_type( $post_id ) == 'events' ) {
	$start = get_post_meta( $post_id, 'event_start', true );
	$end = get_post_meta( $post_id, 'event_end', true );
	if( ( !$end \|\| !$start ) \|\| empty( $start ) \|\| empty( $end ) ) {
	// Update post 37
	$my_post = array(
	'ID' => $post_id,
	'post_status' => 'draft'
	);
	// Update the post into the database
	wp_update_post( $my_post );
	}
	}
	}