Stripe.api_key = "sk_test_g2TLmErk9839IIiTqP7S3Y1F"; post("/create-customer-portal-session", (request, response) -> { // Authenticate your user. SessionCreateParams params = SessionCreateParams.builder() .setCustomer("{{ CUSTOMER_ID }}") .setReturnUrl("https://example.com/account") .build(); Session session = Session.create(params); response.redirect(session.getUrl()); });