Rewrite rule to prettify two $_GET variables while in a new endpoint from a page

Question

I'm trying to create a permalink rule which is a few levels deep.

I have a basic page /page-slug/ - I'm appending to it a new endpoint: /page-slug/my-endpoint/ - from here I need to nest one id and one string that contain $_GET variables, such as /page-slug/my-endpoint/?some_id=123&some_string=string which should become: /page-slug/my-endpoint/123/string/

I got all the query vars successfully registered and I can grab them for use in my methods (e.g if I do var_dump( $wp_query->query_vars ) they will show up where set via $_GET).

What I can't get to work is the rewrite rule to turn a URL in a pretty permalink (this snippet is run at init hook time):

    foreach ( $this->query_vars as $key => $var ) {

        add_rewrite_endpoint( $var, EP_PERMALINK | EP_PAGES, $var );

        if ( 'my-endpoint' == $key ) {

            add_rewrite_tag( '%some_id%',   '([^&]+)' );
            add_rewrite_tag( '%some_string%', '([^&]+)' );

            $page_id   = get_some_page_id(); 
            $page_slug = get_post( $page_id )->post_name;

            // e.g. /page-slug/my-endpoint/123/some-string/
            add_rewrite_rule(
                "{$page_slug}/{$var}/([^/]*)/([^/]*)/?$",
                'index.php?page_id=' . $page_id . '&some_id=$matches[1]&some_string=$matches[2]',
                'top'
            );

        }
    }

I tested the regex and does not look wrong, it catches what I need (123 and some-string).

Up to 'page-slug/' and also 'page-slug/my-query-var/ (2 levels deep) it works just fine, it's the two rewrite tags that don't work when used in a pretty permalink structure.

I tried with https://wordpress.org/plugins/monkeyman-rewrite-analyzer/ and the rules show up there - but I'm not sure about their interpretation

Answer 1

I think you are using endpoints incorrectly. When a endopoint is created, a new rewrite rule is created using a query var with the same name of the endpoint; its value is taken from the string that follows the endpoint definition. So, if you register "my-endpoint" and build this URL:

/page-slug/my-endpoint/123/some-string

The endpoint is passed as my-endpoint=123/some-string.

As far I understand from your code, you don't need the my-endpoint query var, so you don't need to register it; or you can register it with false value for query var argument (this argument is not currently documented in codex but exists in source code):

add_rewrite_endpoint( $var, EP_PERMALINK | EP_PAGES, false );

Or, if you want the endpoint only in pages:

add_rewrite_endpoint( $var, EP_PAGES, false );

Also, you check 'my-endpoint' == $key buth then include $var as endpoint name and as part in the URL, not $key.

Without knowing what $this->query_vars and get_some_page_id() are, I can not test your code exactly but this should work:

foreach ( $this->query_vars as $key => $var ) {

    if ( 'my-endpoint' == $key ) {

        add_rewrite_tag( '%some_id%',   '([^&]+)' );
        add_rewrite_tag( '%some_string%', '([^&]+)' );

        $page_id   = get_some_page_id(); 
        $page_slug = get_post( $page_id )->post_name;

        // e.g. /page-slug/my-endpoint/123/some-string/
        // $key is equal to my-endpoint here because of the previous check
        add_rewrite_rule(
            "^{$page_slug}/{$key}/([^/]*)/([^/]*)/?$",
            'index.php?page_id=' . $page_id . '&some_id=$matches[1]&some_string=$matches[2]',
            'top'
        );

    }
}

Note: Do not forget to flush rewrite rules before testing this code.