Querying WordPress Multisite Sites With Meta Queries

The requirement is very simple. I need to query sites in Multisite by custom site meta value.

After creating sub site, I have added custom site meta to each site with update_site_meta.

update_site_meta($site_id, 'country', 'canada');

The WP_Site_Query was introduced to allow a faster way to query sites in a WordPress Multisite setup.

// WP_Site_Query arguments
$args = array(
    'meta_query' => array(
        array(
            'key'   => 'country',
            'value' => 'australia'
        )
    )
);

// The Site Query
$site_query = new WP_Site_Query( $args );