How do I set a custom order validator for shipping rates (for subscriptions)?

Shipping rates can define a subscription order validator to determine whether they are available for a particular subscription order.

For example, you may want to make a shipping rate available for one-time orders but explicitly opt it into subscription orders.

First, define an availability setting:

\Aero\Cart\Models\ShippingRate::settings('availability', function (\Aero\Common\Settings\ModelSettingGroup $group) {
    $group->boolean('for_subscription_orders')->default(false);
});

The setSubscriptionOrderValidator method can then use this setting to determine whether the shipping rate is available for subscription orders:

\Aero\Cart\Models\ShippingRate::setSubscriptionOrderValidator(function (\Aero\Cart\Models\ShippingRate $rate) {
    return $rate->setting('availability.for_subscription_orders');
});

The validator receives the shipping rate, order and subscription plan and should return true when it can be used for the order, or false when it should be excluded.

Parameters