HM_Rewrite and HM_Rewrite_Rule are wrappers for the WordPress rewrite / wp_query system.
The goal of HM_Rewrite and associated fuctions / classes is to make it very easy to add new routing points with new pages (as in dynamic pages, post_type_archive etc). It basically wraps a few tasks into a nice API. Everything (almost) you need for setting up a new routing page can be done all at once, relying heavily on PHP Closures. It essentially wraps adding to the rewrite_rules, adding your template file to template_redirect, wp_title hook, body_class hook, parse_query hook etc. Also also provides some callbacks for conveniance. Each rewrite rule is an instance of HM_Rewrite_Rule. Here you add the regex / wp_query vars and any other options for the "page". For example a callback function to parse_request to add additional query vars, or a callback * body_class. There is also a wrapper function for all of this in one call hm_add_rewrite_rule(). hm_add_rewrite_rule() is generally the recommended interface, you can interact with the underlying objects for more advanced stuff (and also tacking onto other rewrite rules)Simple use case example:
hm_add_rewrite_rule( array(
'regex' => '^users/([^/]+)/?',
'query' => 'author_name=$matches[1]',
'template' => 'user-archive.php',
'body_class_callback' => function( $classes ) {
$classes[] = 'user-archive';
$classes[] = 'user-' . get_query_var( 'author_name' );
return $classes;
},
'title_callback' => function( $title, $seperator ) {
return get_query_var( 'author_name' ) . ' ' . $seperator . ' ' . $title;
} ) );A more advanced example using more callbacks:
hm_add_rewrite_rule( array(
'regex' => '^reviews/([^/]+)/?', // a review category page
'query' => 'review_category=$matches[1]',
'template' => 'review-category.php',
'request_callback' => function( WP $wp ) {
// if the review category is "laptops" then only show items in draft
if ( $wp->query_vars['review_category'] == 'laptops' )
$wp->query_vars['post_status'] = 'draft';
},
'query_callback' => function( WP_Query $query ) {
//overwrite is_home because WordPress gets it wrong here
$query->is_home = false;
},
'body_class_callback' => function( $classes ) {
$classes[] = get_query_var( 'review_category' );
return $classes;
},
'title_callback' => function( $title, $seperator ) {
return review_category . ' ' . $seperator . ' ' . $title;
}
)
);see https://github.com/humanmade/hm-rewrite/blob/master/CONTRIBUTING.md