Category URL's 404 after setting category base to '.'

Question

I want to remove /category from URLs. I have set category base to "."

I have some "category urls" which previously looked like /category/category-name/sub-category-name They are now /category-name/sub-category-name These urls previously rendered pages that would list all the posts attached to that category. They now return 404s.

Where can I look to debug this?

Answer 1

Try to flush permalinks by going to (Settings > Permalinks) and click save without making changes.

Answer 2

Sometimes you need to write new actions. To solve the category base problem you need to add and remove some actions. You can try this code as a custom plugin. Probably this can solve your problem. The code completely removes /category/ base.

Add this code to your theme's functions.php or create a custom plugin with this code.

/**
 * Add some actions to flush rewrite rules
 */

add_action('created_category', 'flush_rewrite_rules_f_custom');
add_action('delete_category', 'flush_rewrite_rules_f_custom');
add_action('edited_category', 'flush_rewrite_rules_f_custom');

// Init function

add_action('init', 'remove_url_perma_cat');

function flush_rewrite_rules_f_custom()
{
    global $wp_rewrite;
    $wp_rewrite->flush_rules();
}

function remove_url_perma_cat()
{
    global $wp_rewrite;
    $wp_rewrite->extra_permastructs['category'][0] = '%category%';
}

/**
 * Add some filter for redirect
 */

add_filter('category_rewrite_rules', 'remo_rew_rul_c');
add_filter('query_vars', 'remo_q_vars_c');
add_filter('request', 'remo_crw_req');

/**
 * Remove catergory base and redirect
 */
function remo_rew_rul_c($category_rewrite)
{
    global $wp_rewrite;

    $category_rewrite = array();

    $categories = get_categories(array( 'hide_empty' => false ));

    foreach ($categories as $category) {
        $category_nicename = $category->slug;
        if ($category->parent == $category->cat_ID) {
            $category->parent = 0;
        } elseif (0 != $category->parent) {
            $category_nicename = get_category_parents($category->parent, false, '/', true) . $category_nicename;
        }
        $category_rewrite[ '(' . $category_nicename . ')/(?:feed/)?(feed|rdf|rss|rss2|atom)/?$' ] = 'index.php?category_name=$matches[1]&feed=$matches[2]';
        $category_rewrite[ '(' . $category_nicename . ')/page/?([0-9]{1,})/?$' ] = 'index.php?category_name=$matches[1]&paged=$matches[2]';
        $category_rewrite[ '(' . $category_nicename . ')/?$' ] = 'index.php?category_name=$matches[1]';
    }

    $old_category_base = get_option('category_base') ? get_option('category_base') : 'category';
    $old_category_base = trim($old_category_base, '/');
    $category_rewrite[ $old_category_base . '/(.*)$' ] = 'index.php?crw=$matches[1]';

    return $category_rewrite;
}

/**
 * New Query Vars : crw
 */
function remo_q_vars_c($public_query_vars)
{
    $public_query_vars[] = 'crw';

    return $public_query_vars;
}

/**
 * Redirect based crw
 */
function remo_crw_req($query_vars)
{
    if (isset($query_vars['crw'])) {
        $catlink = trailingslashit(get_option('home')) . user_trailingslashit($query_vars['crw'], 'category');
        status_header(301);
        header("Location: $catlink");
        exit;
    }
}

Answer 3

If you are using Apache then add the following to the end of .htaccess in the root of your WordPress installation. This will perform the redirection automatically for you.

Note: Replace http://www.example.com with your site URL.

RewriteRule ^category/(.+)$ http://www.example.com/$1 [R=301,L]

Answer 4

Did you try to filter the $wp_query object? You can use this code snippet to search for the category slug directly in DB:

function pm_detect_term_slugs($query) {
    global $wpdb;

    // Do not run when Elementor is opened
    if((!empty($_REQUEST['action']) && strpos($_REQUEST['action'], 'elementor') !== false) || isset($_REQUEST['elementor-preview'])) {
        return $query;
    }

    // 1. Get the slug
    if(!empty($query['pagename'])) {
        $slug = $query['pagename'];
    } else if(!empty($query['name'])) {
        $slug = $query['name'];
    } else if(!empty($query['attachment'])) {
        $slug = $query['attachment'];
    }

    if(!empty($slug)) {
        $slug = basename($slug);

        // 2. Check if the slug is assigned to any post item
        $sql_query = "SELECT t.slug, t.term_id, tt.taxonomy FROM $wpdb->terms AS t INNER JOIN $wpdb->term_taxonomy AS tt ON(tt.term_id = tt.term_id) WHERE 1=1 AND slug = %s";
        $term = $wpdb->get_row($wpdb->prepare($sql_query, array($slug)));

        // 3. Filter the query if any term was found
        if(!empty($term->taxonomy)) {
            $page = (!empty($query['paged'])) ? $query['paged'] : 1;

            $new_query = array(
                'term' => $term->slug,
                'taxonomy' => $term->taxonomy,
                'paged' => $page
            );

            // 4. Disable canonical redirect
            remove_action('template_redirect', 'wp_old_slug_redirect');
            remove_action('template_redirect', 'redirect_canonical');
            add_filter('wpml_is_redirected', '__return_false', 99, 2);
            add_filter('pll_check_canonical_url', '__return_false', 99, 2);

            return $new_query;
        }
    }
    return $query;
}
add_filter('request', 'pm_detect_term_slugs', 9999);

Alternatively you can use my plugin Permalink Manager Pro to filter the category permalinks: https://permalinkmanager.pro/docs/basics/bulk-edit-wordpress-permalinks