flush_rewrite_rules( bool $hard = true )
Remove rewrite rules and then recreate rewrite rules.
Parameters Parameters
- $hard
-
(bool) (Optional) Whether to update .htaccess (hard flush) or just update rewrite_rules option (soft flush). Default is true (hard).
Default value: true
More Information More Information
This function is useful when used with custom post types as it allows for automatic flushing of the WordPress rewrite rules (usually needs to be done manually for new custom post types). However, this is an expensive operation so it should only be used when necessary.
Source Source
File: wp-includes/rewrite.php
function flush_rewrite_rules( $hard = true ) {
global $wp_rewrite;
if ( is_callable( array( $wp_rewrite, 'flush_rules' ) ) ) {
$wp_rewrite->flush_rules( $hard );
}
}
Expand full source code Collapse full source code View on Trac
Changelog Changelog
| Version | Description |
|---|---|
| 3.0.0 | Introduced. |
User Contributed Notes User Contributed Notes
You must log in before being able to contribute a note or feedback.
register_activation_hook( __FILE__, 'plugin_activation' ); function plugin_activation() { update_option('plugin_permalinks_flushed', 0); } add_action( 'init', 'custom_query_vars' ); function custom_query_vars() { global $wp; $wp->add_query_var( 'newfeed' ); add_rewrite_rule( '^newfeed/([^/]*)/?', 'index.php?newfeed=$matches[1]', 'top' ); if( !get_option('plugin_permalinks_flushed') ) { flush_rewrite_rules(false); update_option('plugin_permalinks_flushed', 1); } }Expand full source codeCollapse full source code
If you want to flush rules while updating posts based on post type:
function wpdoc_flush_rules_on_save_posts( $post_id ) { // Check the correct post type. // Example to check, if the post type isn't 'post' then don't flush, just return. if ( ! empty( $_POST['post_type'] && $_POST['post_type'] != 'post' ) { return; } flush_rewrite_rules(); } add_action( 'save_post', 'wpdoc_flush_rules_on_save_posts', 20, 2);Expand full source codeCollapse full source code
This is how you would flush rules on theme activation:
If you’re developing a theme, while building it you can use this snippet of code that will flush rewrite rules when the file containing it is changed, or every 48 hours:
// do not use on live/production servers add_action( 'init','maybe_rewrite_rules' ); /** * Flush rewrite rules if the current file has changed and at least every 48 hours. */ function maybe_rewrite_rules() { if ( ! is_admin() ) { return; } $ver = filemtime( __FILE__ ); // Get the file time for this file as the version number $defaults = array( 'version' => 0, 'time' => time() ); $r = wp_parse_args( get_option( __CLASS__ . '_flush', array() ), $defaults ); if ( $r['version'] != $ver || $r['time'] + 172800 < time() ) { // Flush if ver changes or if 48hrs has passed. flush_rewrite_rules(); // trace( 'flushed' ); $args = array( 'version' => $ver, 'time' => time() ); if ( ! update_option( __CLASS__ . '_flush', $args ) ) add_option( __CLASS__ . '_flush', $args ); } }Expand full source codeCollapse full source code
Feedback
“Flushing” the rewrite rules should only happen in wp-admin, see https://core.trac.wordpress.org/ticket/44142. It is possible to do from the front-end while developing a theme or a plugin, but is a pretty bad idea if ever done in production.In that terms I’d add:
if ( ! is_admin() ) { return; }at the top of the above function. — By Andrew Ozz —A relatively simple way to flush rewrite rules on activation and deactivation hooks is not using flush_rewrite_rules() at all. Instead just clear the rewrite_rules option to force WordPress to recreate them at the right time.
Example:
register_activation_hook( __FILE__, 'wpdocs_wpdev_activate' ); function wpdocs_wpdev_activate() { // force rewrite rules to be recreated at the right time delete_option( 'rewrite_rules' ); }This avoids having to do complicated stuff like registering your custom post types in the activation hook or throwing and catching dedicated db option or transients as suggested in other notes…
This is how you would flush rewrite rules when a plugin is activated or deactivated:
register_deactivation_hook( __FILE__, 'flush_rewrite_rules' ); register_activation_hook( __FILE__, 'wdocs_flush_rewrites' ); /** * Flush rewrite rules on activation */ function wpdocs_flush_rewrites() { // call your CPT registration function here (it should also be hooked into 'init') wpdocs_custom_post_types_registration(); flush_rewrite_rules(); }Expand full source codeCollapse full source code
// flush rules and serve new rules instantly without page refresh add_action('init', function() { flush_rewrite_rules(); }); // Or, hook into wp tag, flush rules and do an internal refresh add_action('wp', function() { if( "1" !== get_option("my_rules_have_been_flushed") ) { flush_rewrite_rules(); update_option('my_rules_have_been_flushed', '1'); // now, redirect the request. wp_redirect( $_SERVER['REQUEST_URI'] ); exit; } });Expand full source codeCollapse full source code