From b5b6111e8388d19a394c5e19f7ab2cfb77112b41 Mon Sep 17 00:00:00 2001
From: Laurent Cozic <laurent@cozic.net>
Date: Sat, 31 Jul 2021 17:05:39 +0100
Subject: [PATCH] Server: Allows providing a coupon when creating the Stripe
 checkout session

---
 Assets/WebsiteAssets/templates/plans.mustache | 17 +++++++++++++----
 packages/server/src/routes/index/stripe.ts    | 19 +++++++++++++++----
 2 files changed, 28 insertions(+), 8 deletions(-)

diff --git a/Assets/WebsiteAssets/templates/plans.mustache b/Assets/WebsiteAssets/templates/plans.mustache
index 84d0513dc..00383d37d 100644
--- a/Assets/WebsiteAssets/templates/plans.mustache
+++ b/Assets/WebsiteAssets/templates/plans.mustache
@@ -53,7 +53,10 @@
 		var stripe = Stripe('{{{stripeConfig.publishableKey}}}');
 
 		var createCheckoutSession = function(priceId) {
-			console.info('Creating Stripe session for price:', priceId);
+			const urlQuery = new URLSearchParams(location.search);
+			const coupon = urlQuery.get('coupon') || '';
+
+			console.info('Creating Stripe session for price:', priceId, 'Coupon:', coupon);
 
 			return fetch("{{{stripeConfig.webhookBaseUrl}}}/stripe/createCheckoutSession", {
 				method: "POST",
@@ -61,10 +64,16 @@
 					"Content-Type": "application/json"
 				},
 				body: JSON.stringify({
-					priceId: priceId
+					priceId: priceId,
+					coupon: coupon,
 				})
-			}).then(function(result) {
-				return result.json();
+			}).then(async function(result) {
+				if (!result.ok) {
+					console.error('Could not create Stripe checkout session', await result.text());
+					alert('The checkout session could not be created. Please contact support@joplincloud.com for support.');
+				} else {
+					return result.json();
+				}
 			});
 		};
 
diff --git a/packages/server/src/routes/index/stripe.ts b/packages/server/src/routes/index/stripe.ts
index cfc2fca9b..f7b0d6118 100644
--- a/packages/server/src/routes/index/stripe.ts
+++ b/packages/server/src/routes/index/stripe.ts
@@ -33,6 +33,7 @@ async function stripeEvent(stripe: Stripe, req: any): Promise<Stripe.Event> {
 
 interface CreateCheckoutSessionFields {
 	priceId: string;
+	coupon: string;
 }
 
 type StripeRouteHandler = (stripe: Stripe, path: SubPath, ctx: AppContext)=> Promise<any>;
@@ -60,9 +61,7 @@ export const postHandlers: PostHandlers = {
 		const fields = await bodyFields<CreateCheckoutSessionFields>(ctx.req);
 		const priceId = fields.priceId;
 
-		// See https://stripe.com/docs/api/checkout/sessions/create
-		// for additional parameters to pass.
-		const session = await stripe.checkout.sessions.create({
+		const checkoutSession: Stripe.Checkout.SessionCreateParams = {
 			mode: 'subscription',
 			payment_method_types: ['card'],
 			line_items: [
@@ -80,7 +79,19 @@ export const postHandlers: PostHandlers = {
 			// is redirected to the success page.
 			success_url: `${globalConfig().baseUrl}/stripe/success?session_id={CHECKOUT_SESSION_ID}`,
 			cancel_url: `${globalConfig().baseUrl}/stripe/cancel`,
-		});
+		};
+
+		if (fields.coupon) {
+			checkoutSession.discounts = [
+				{
+					coupon: fields.coupon.trim(),
+				},
+			];
+		}
+
+		// See https://stripe.com/docs/api/checkout/sessions/create
+		// for additional parameters to pass.
+		const session = await stripe.checkout.sessions.create(checkoutSession);
 
 		logger.info('Created checkout session', session.id);