Second Custom Post Type Archive

Question

I've got an event custom post type, and using filters, I've configured the archive page to show only event in the future, and in chronological order based on a meta value (start date).

I want to make a second archive page to show events in the past, complete with pagination, ordered reverse chronologically on the same meta value.

My first thought is to use a shortcode inside a normal page, but I'm not sure how to get the pagination working.

Alternatively, is there a way to create a "generic" archive page? Do I need to get into rewrite rules?

Answer 1

I would use a query parameter, something like ?time=future maybe, to shift your query. The difference between the future posts query and the past posts query should just be the orderby and the meta_query, so it should be relatively easy to change that based on the URL parameter. You also have the added benefit of reducing overhead by keeping it to one page. My only concern with this would be linking in the menu, as you'd have to use custom links, and those are less flexible.

Answer 2

This is what I went with. It creates a second archive for past events. It shows upcoming events in the main event archive, and old events in the past events page. Sorting is ascending for the main archive (so you see the next upcoming event first), and descending for the past events page, so you see the most recent event first. It allows for paging on the past events page. Note that is does not modify the query in the admin system.

new My_Events_Are_Special;
class My_Events_Are_Special {

    function __construct() {
        add_filter('rewrite_rules_array', array($this, 'insert_rewrite_rules'));
        add_filter('query_vars', array($this, 'insert_query_vars'));
        add_action('wp_loaded', array($this, 'flush_rules'));
        add_filter('posts_join', array($this, 'posts_join'));
        add_filter('posts_where', array($this, 'posts_where'));
        add_filter('posts_orderby', array($this, 'posts_orderby'));
    }

    function can_modify_query() {
        return !is_admin() && is_post_type_archive('event');
    }

    // create rules for the archived events page
    var $rewrite_rules = array(
        'events/archive$' => 'index.php?post_type=event&archive_type=archive',
        'events/archive/page/([0-9]+)$' => 'index.php?post_type=event&archive_type=archive&paged=$matches[1]',
    );

    // insert rules into rewrite system
    function insert_rewrite_rules($rules) {
        return $this->rewrite_rules + $rules;
    }

    // add special query var to system
    function insert_query_vars($vars) {
        array_push($vars, 'archive_type');
        return $vars;
    }

    // flush rules if any are new
    function flush_rules() {
        $rules = get_option('rewrite_rules');
        $flush = false;

        foreach ($this->rewrite_rules as $rule => $rewrite) {
            if (!isset($rules[$rule])) {
                global $wp_rewrite;
                $wp_rewrite->flush_rules();
                break;
            }
        }
    }

    // add start and end type to query for events (not in admin)
    function posts_join($join) {
        global $wpdb;
        if ($this->can_modify_query()) {
            $join .= " JOIN $wpdb->postmeta starts on ($wpdb->posts.ID = starts.post_id AND starts.meta_key = '_starts') ";
            $join .= " JOIN $wpdb->postmeta ends on ($wpdb->posts.ID = ends.post_id AND ends.meta_key = '_ends') ";
        }
        return $join;
    }

    // only show future events for the main archive, only past events for the "archive archive"
    function posts_where($where) {
        global $wpdb;
        if ($this->can_modify_query()) {
            $compare = get_query_var('archive_type') == 'archive' ? '<' : '>';
            $where .= " AND ends.meta_value $compare ".time();
        }
        return $where;
    }

    // main archive is ordered ascending on event start date, "archive archive" is ordered descending
    function posts_orderby($orderby) {
        global $wpdb;
        if ($this->can_modify_query()) {
            $order = get_query_var('archive_type') == 'archive' ? 'DESC' : 'ASC';
            $orderby = "starts.meta_value $order, $wpdb->posts.post_date $order";
        }
        return $orderby;
    }
}