Themes and the hourly refresh

The themes, their categories and the subscriber fields come from the platform in one request. Your site keeps them in a cache, so the form editor never waits for the platform.

When the platform is contacted

Where	Uses the cache	Contacts the platform when nothing is cached
Saving Forms > Settings > Wereldkundig	no, always fetches	yes
The background refresh, every hour	no, always fetches	yes
The form editor: the Themes setting	yes	no
The settings page: connection status	yes	no
A feed’s Map Fields	yes	yes
A submission: checking the themes	yes	yes

The form editor never contacts the platform. Gravity Forms rebuilds the editor after every form save, so a slow or unreachable platform would otherwise slow down saving every form.

The cache belongs to the platform URL and Basic Auth code: change either one, and the themes are fetched again. A failed fetch never replaces the cache, so the themes you had keep working.

The background refresh

The cache doesn’t expire by itself. It is refreshed:

• in the background by WP-Cron, every hour, so new themes show up within the hour;
• right away when you save the Wereldkundig settings.

The refresh is scheduled while the platform is connected, and removed when the credentials are removed, or when the add-on is deactivated or uninstalled. The first run is one hour after it is scheduled.

Change the interval with a WP-Cron schedule name. Unknown names fall back to hourly:

add_filter('wk_gf_refresh_fields_recurrence', function () {
    return 'twicedaily';
});

Change the delay before the first run, in seconds, with wk_gf_refresh_fields_initial_delay.

WP-Cron

WP-Cron only runs when the site gets visits. On a site with little traffic, or with DISABLE_WP_CRON, let the server call wp-cron.php, or run wp cron event run --due-now.

Run the refresh by hand with WP-CLI:

wp cron event run wk_gf_refresh_fields
# On multisite, per site:
wp cron event run wk_gf_refresh_fields --url=example.nl/site

A theme was removed on the platform

A subscribe field that still has a removed theme checked fails with Invalid Wereldkundig theme on submit. Its other themes are still subscribed. Open the form, check the field’s themes and save the form.