feat: add multi subscription support (#734)

## Description

Previously we assumed that there can only be 1 subscription per user.
However, that will soon no longer the case with the introduction of the
Teams subscription.

This PR will apply the required migrations to support multiple
subscriptions.

## Changes Made

- Updated the Prisma schema to allow for multiple `Subscriptions` per
`User`
- Added a Stripe `customerId` field to the `User` model
- Updated relevant billing sections to support multiple subscriptions

## Testing Performed

- Tested running the Prisma migration on a demo database created on the
main branch

Will require a lot of additional testing.

## Checklist

- [ ] I have tested these changes locally and they work as expected.
- [ ] I have added/updated tests that prove the effectiveness of these
changes.
- [X] I have followed the project's coding style guidelines.

## Additional Notes

Added the following custom SQL statement to the migration:

> DELETE FROM "Subscription" WHERE "planId" IS NULL OR "priceId" IS
NULL;

Prior to deployment this will require changes to Stripe products:
- Adding `type` meta attribute

---------

Co-authored-by: Lucas Smith <me@lucasjamessmith.me>

packages/ee/server-only/stripe/create-customer.ts

@@ -1,31 +0,0 @@
-import { stripe } from '@documenso/lib/server-only/stripe';
-import { getSubscriptionByUserId } from '@documenso/lib/server-only/subscription/get-subscription-by-user-id';
-import { prisma } from '@documenso/prisma';
-import { User } from '@documenso/prisma/client';
-
-export type CreateCustomerOptions = {
-  user: User;
-};
-
-export const createCustomer = async ({ user }: CreateCustomerOptions) => {
-  const existingSubscription = await getSubscriptionByUserId({ userId: user.id });
-
-  if (existingSubscription) {
-    throw new Error('User already has a subscription');
-  }
-
-  const customer = await stripe.customers.create({
-    name: user.name ?? undefined,
-    email: user.email,
-    metadata: {
-      userId: user.id,
-    },
-  });
-
-  return await prisma.subscription.create({
-    data: {
-      userId: user.id,
-      customerId: customer.id,
-    },
-  });
-};

packages/ee/server-only/stripe/get-customer.ts

@@ -1,4 +1,8 @@
 import { stripe } from '@documenso/lib/server-only/stripe';
+import { prisma } from '@documenso/prisma';
+import type { User } from '@documenso/prisma/client';
+
+import { onSubscriptionUpdated } from './webhook/on-subscription-updated';
 
 export const getStripeCustomerByEmail = async (email: string) => {
   const foundStripeCustomers = await stripe.customers.list({
@@ -17,3 +21,74 @@ export const getStripeCustomerById = async (stripeCustomerId: string) => {
     return null;
   }
 };
+
+/**
+ * Get a stripe customer by user.
+ *
+ * Will create a Stripe customer and update the relevant user if one does not exist.
+ */
+export const getStripeCustomerByUser = async (user: User) => {
+  if (user.customerId) {
+    const stripeCustomer = await getStripeCustomerById(user.customerId);
+
+    if (!stripeCustomer) {
+      throw new Error('Missing Stripe customer');
+    }
+
+    return {
+      user,
+      stripeCustomer,
+    };
+  }
+
+  let stripeCustomer = await getStripeCustomerByEmail(user.email);
+
+  const isSyncRequired = Boolean(stripeCustomer && !stripeCustomer.deleted);
+
+  if (!stripeCustomer) {
+    stripeCustomer = await stripe.customers.create({
+      name: user.name ?? undefined,
+      email: user.email,
+      metadata: {
+        userId: user.id,
+      },
+    });
+  }
+
+  const updatedUser = await prisma.user.update({
+    where: {
+      id: user.id,
+    },
+    data: {
+      customerId: stripeCustomer.id,
+    },
+  });
+
+  // Sync subscriptions if the customer already exists for back filling the DB
+  // and local development.
+  if (isSyncRequired) {
+    await syncStripeCustomerSubscriptions(user.id, stripeCustomer.id).catch((e) => {
+      console.error(e);
+    });
+  }
+
+  return {
+    user: updatedUser,
+    stripeCustomer,
+  };
+};
+
+const syncStripeCustomerSubscriptions = async (userId: number, stripeCustomerId: string) => {
+  const stripeSubscriptions = await stripe.subscriptions.list({
+    customer: stripeCustomerId,
+  });
+
+  await Promise.all(
+    stripeSubscriptions.data.map(async (subscription) =>
+      onSubscriptionUpdated({
+        userId,
+        subscription,
+      }),
+    ),
+  );
+};

packages/ee/server-only/stripe/get-prices-by-interval.ts

@@ -1,4 +1,4 @@
-import Stripe from 'stripe';
+import type Stripe from 'stripe';
 
 import { stripe } from '@documenso/lib/server-only/stripe';
 
@@ -7,7 +7,14 @@ type PriceWithProduct = Stripe.Price & { product: Stripe.Product };
 
 export type PriceIntervals = Record<Stripe.Price.Recurring.Interval, PriceWithProduct[]>;
 
-export const getPricesByInterval = async () => {
+export type GetPricesByIntervalOptions = {
+  /**
+   * Filter products by their meta 'type' attribute.
+   */
+  type?: 'individual';
+};
+
+export const getPricesByInterval = async ({ type }: GetPricesByIntervalOptions = {}) => {
   let { data: prices } = await stripe.prices.search({
     query: `active:'true' type:'recurring'`,
     expand: ['data.product'],
@@ -19,8 +26,10 @@ export const getPricesByInterval = async () => {
     // eslint-disable-next-line @typescript-eslint/consistent-type-assertions
     const product = price.product as Stripe.Product;
 
+    const filter = !type || product.metadata?.type === type;
+
     // Filter out prices for products that are not active.
-    return product.active;
+    return product.active && filter;
   });
 
   const intervals: PriceIntervals = {

packages/ee/server-only/stripe/get-prices-by-type.ts

@@ -0,0 +1,11 @@
+import { stripe } from '@documenso/lib/server-only/stripe';
+
+export const getPricesByType = async (type: 'individual') => {
+  const { data: prices } = await stripe.prices.search({
+    query: `metadata['type']:'${type}' type:'recurring'`,
+    expand: ['data.product'],
+    limit: 100,
+  });
+
+  return prices;
+};

packages/ee/server-only/stripe/webhook/handler.ts

@@ -75,23 +75,23 @@ export const stripeWebhookHandler = async (
 
         // Finally, attempt to get the user ID from the subscription within the database.
         if (!userId && customerId) {
-          const result = await prisma.subscription.findFirst({
+          const result = await prisma.user.findFirst({
             select: {
-              userId: true,
+              id: true,
             },
             where: {
               customerId,
             },
           });
 
-          if (!result?.userId) {
+          if (!result?.id) {
             return res.status(500).json({
               success: false,
               message: 'User not found',
             });
           }
 
-          userId = result.userId;
+          userId = result.id;
         }
 
         const subscriptionId =
@@ -124,23 +124,23 @@ export const stripeWebhookHandler = async (
             ? subscription.customer
             : subscription.customer.id;
 
-        const result = await prisma.subscription.findFirst({
+        const result = await prisma.user.findFirst({
           select: {
-            userId: true,
+            id: true,
           },
           where: {
             customerId,
           },
         });
 
-        if (!result?.userId) {
+        if (!result?.id) {
           return res.status(500).json({
             success: false,
             message: 'User not found',
           });
         }
 
-        await onSubscriptionUpdated({ userId: result.userId, subscription });
+        await onSubscriptionUpdated({ userId: result.id, subscription });
 
         return res.status(200).json({
           success: true,
@@ -182,23 +182,23 @@ export const stripeWebhookHandler = async (
           });
         }
 
-        const result = await prisma.subscription.findFirst({
+        const result = await prisma.user.findFirst({
           select: {
-            userId: true,
+            id: true,
           },
           where: {
             customerId,
           },
         });
 
-        if (!result?.userId) {
+        if (!result?.id) {
           return res.status(500).json({
             success: false,
             message: 'User not found',
           });
         }
 
-        await onSubscriptionUpdated({ userId: result.userId, subscription });
+        await onSubscriptionUpdated({ userId: result.id, subscription });
 
         return res.status(200).json({
           success: true,
@@ -233,23 +233,23 @@ export const stripeWebhookHandler = async (
           });
         }
 
-        const result = await prisma.subscription.findFirst({
+        const result = await prisma.user.findFirst({
           select: {
-            userId: true,
+            id: true,
           },
           where: {
             customerId,
           },
         });
 
-        if (!result?.userId) {
+        if (!result?.id) {
           return res.status(500).json({
             success: false,
             message: 'User not found',
           });
         }
 
-        await onSubscriptionUpdated({ userId: result.userId, subscription });
+        await onSubscriptionUpdated({ userId: result.id, subscription });
 
         return res.status(200).json({
           success: true,

packages/ee/server-only/stripe/webhook/on-subscription-deleted.ts

@@ -1,4 +1,4 @@
-import { Stripe } from '@documenso/lib/server-only/stripe';
+import type { Stripe } from '@documenso/lib/server-only/stripe';
 import { prisma } from '@documenso/prisma';
 import { SubscriptionStatus } from '@documenso/prisma/client';
 
@@ -7,12 +7,9 @@ export type OnSubscriptionDeletedOptions = {
 };
 
 export const onSubscriptionDeleted = async ({ subscription }: OnSubscriptionDeletedOptions) => {
-  const customerId =
-    typeof subscription.customer === 'string' ? subscription.customer : subscription.customer?.id;
-
   await prisma.subscription.update({
     where: {
-      customerId,
+      planId: subscription.id,
     },
     data: {
       status: SubscriptionStatus.INACTIVE,

packages/ee/server-only/stripe/webhook/on-subscription-updated.ts

@@ -1,6 +1,6 @@
 import { match } from 'ts-pattern';
 
-import { Stripe } from '@documenso/lib/server-only/stripe';
+import type { Stripe } from '@documenso/lib/server-only/stripe';
 import { prisma } from '@documenso/prisma';
 import { SubscriptionStatus } from '@documenso/prisma/client';
 
@@ -13,9 +13,6 @@ export const onSubscriptionUpdated = async ({
   userId,
   subscription,
 }: OnSubscriptionUpdatedOptions) => {
-  const customerId =
-    typeof subscription.customer === 'string' ? subscription.customer : subscription.customer?.id;
-
   const status = match(subscription.status)
     .with('active', () => SubscriptionStatus.ACTIVE)
     .with('past_due', () => SubscriptionStatus.PAST_DUE)
@@ -23,22 +20,22 @@ export const onSubscriptionUpdated = async ({
 
   await prisma.subscription.upsert({
     where: {
-      customerId,
+      planId: subscription.id,
     },
     create: {
-      customerId,
       status: status,
       planId: subscription.id,
       priceId: subscription.items.data[0].price.id,
       periodEnd: new Date(subscription.current_period_end * 1000),
       userId,
+      cancelAtPeriodEnd: subscription.cancel_at_period_end,
     },
     update: {
-      customerId,
       status: status,
       planId: subscription.id,
       priceId: subscription.items.data[0].price.id,
       periodEnd: new Date(subscription.current_period_end * 1000),
+      cancelAtPeriodEnd: subscription.cancel_at_period_end,
     },
   });
 };