You may optionally implement a promo code validation endpoint for Web Payment subscriptions. If you don’t implement this endpoint then the promo code input on the checkout page in the web app will only be used to validate promo codes for Stripe and group membership subscriptions. If you do implement this endpoint then the input will also be used to validate promo codes for Web Payment subscriptions.

Promo codes that you create for Web Payment subscriptions must only be letters a-z and numbers, and your validation must be case insensitive. Promo codes that contain characters besides letters a-z and numbers will automatically be considered invalid, without a request being sent to your API.

When a user enters a promo code in the web app, the web app sends it to the Treefort API, which sends it to your API via a POST request. Depending on the response from your API, a valid or invalid promo code message is shown to the user.