Functions: Handle "charge.updated" events to process updated balance …

…transactions from Stripe

functions/src/webhooks/stripe/index.ts

@@ -1,7 +1,6 @@
 import { DocumentReference, DocumentSnapshot } from 'firebase-admin/firestore';
 import { logger } from 'firebase-functions';
 import { onRequest } from 'firebase-functions/v2/https';
-import Stripe from 'stripe';
 import { FirestoreAdmin } from '../../../../shared/src/firebase/admin/FirestoreAdmin';
 import { SendgridSubscriptionClient } from '../../../../shared/src/sendgrid/SendgridSubscriptionClient';
 import { StripeEventHandler } from '../../../../shared/src/stripe/StripeEventHandler';
@@ -43,12 +42,14 @@ export default onRequest(async (request, response) => {
 	try {
 		const sig = request.headers['stripe-signature']!;
 		const event = stripeEventHandler.constructWebhookEvent(request.rawBody, sig, STRIPE_WEBHOOK_SECRET);
-		const charge = event.data.object as Stripe.Charge;
 		switch (event.type) {
 			case 'charge.succeeded':
+			// The charge.succeeded events do sometimes not contain the balance_transaction, so we need to listen to charge.updated event
+			// to get the final balance_transaction and update the contribution document with the final amount.
+			case 'charge.updated':
 			case 'charge.failed': {
-				const contributionRef = await stripeEventHandler.handleChargeEvent(charge);
-				logger.info(`Charge event ${event.type} handled for charge ${charge.id}.`);
+				const contributionRef = await stripeEventHandler.handleChargeEvent(event.data.object);
+				logger.info(`Charge event ${event.type} handled for charge ${event.data.object.id}.`);
 				if (contributionRef) {
 					logger.info(`Created contribution ${contributionRef.id}. Adding contributor to newsletter.`);
 					try {

shared/src/stripe/StripeEventHandler.ts

@@ -33,12 +33,12 @@ export class StripeEventHandler {
 
 		const checkoutMetadata = await this.getCheckoutMetadata(charge);
 
-		// We only store non-successful charges if the user already exists.
-		// This prevents us from having users in the database that never made a successful contribution.
-		if (
-			fullCharge.status === 'succeeded' ||
-			(await this.findFirestoreUser(await this.retrieveStripeCustomer(fullCharge.customer as string)))
-		) {
+		const firestoreUser = await this.findFirestoreUser(
+			await this.retrieveStripeCustomer(fullCharge.customer as string),
+		);
+		if (fullCharge.status === 'succeeded' || firestoreUser) {
+			// We only store non-successful charges if the user already exists.
+			// This prevents us from having users in the database that never made a successful contribution.
 			return await this.storeCharge(fullCharge, checkoutMetadata);
 		}
 		return null;
@@ -101,6 +101,7 @@ export class StripeEventHandler {
 		const plan = (charge.invoice as Stripe.Invoice)?.lines?.data[0]?.plan;
 		const monthlyInterval = plan?.interval === 'month' ? plan?.interval_count : plan?.interval === 'year' ? 12 : 0;
 		const balanceTransaction = charge.balance_transaction as Stripe.BalanceTransaction;
+
 		const contribution = {
 			source: ContributionSourceKey.STRIPE,
 			created: toFirebaseAdminTimestamp(DateTime.fromSeconds(charge.created)),
@@ -205,8 +206,8 @@ export class StripeEventHandler {
 		const contributionRef = (
 			userRef.collection(CONTRIBUTION_FIRESTORE_PATH) as CollectionReference<StripeContribution>
 		).doc(charge.id);
-		await contributionRef.set(contribution);
-		console.info(`Ingested ${charge.id} into firestore for user ${userRef.id}`);
+		await contributionRef.set(contribution, { merge: true });
+		console.info(`Updated contribution document: ${contributionRef.path}`);
 		await this.maybeUpdateCampaign(contribution);
 		return contributionRef;
 	};