Add metered product to checkout session (#9788)

Solves twentyhq/private-issues#238

**TLDR:**
Add metered product in the checkout session when purchasing a
subscription

**In order to test:**

1. Have the environment variable IS_BILLING_ENABLED set to true and add
the other required environment variables for Billing to work
2. Do a database reset (to ensure that the new feature flag is properly
added and that the billing tables are created)
3. Run the command: npx nx run twenty-server:command
billing:sync-plans-data (if you don't do that the products and prices
will not be present in the database)
4. Run the server , the frontend, the worker, and the stripe listen
command (stripe listen --forward-to
http://localhost:3000/billing/webhooks)
5. Buy a subscription for the Acme workspace , in the checkout session
you should see that there is two products

packages/twenty-server/src/engine/core-modules/billing/billing.exception.ts

@@ -11,6 +11,7 @@ export class BillingException extends CustomException {
 
 export enum BillingExceptionCode {
   BILLING_CUSTOMER_NOT_FOUND = 'BILLING_CUSTOMER_NOT_FOUND',
+  BILLING_PLAN_NOT_FOUND = 'BILLING_PLAN_NOT_FOUND',
   BILLING_PRODUCT_NOT_FOUND = 'BILLING_PRODUCT_NOT_FOUND',
   BILLING_PRICE_NOT_FOUND = 'BILLING_PRICE_NOT_FOUND',
   BILLING_SUBSCRIPTION_EVENT_WORKSPACE_NOT_FOUND = 'BILLING_SUBSCRIPTION_EVENT_WORKSPACE_NOT_FOUND',

packages/twenty-server/src/engine/core-modules/billing/billing.resolver.ts

@@ -16,6 +16,7 @@ import { BillingPlanService } from 'src/engine/core-modules/billing/services/bil
 import { BillingPortalWorkspaceService } from 'src/engine/core-modules/billing/services/billing-portal.workspace-service';
 import { BillingSubscriptionService } from 'src/engine/core-modules/billing/services/billing-subscription.service';
 import { StripePriceService } from 'src/engine/core-modules/billing/stripe/services/stripe-price.service';
+import { BillingPortalCheckoutSessionParameters } from 'src/engine/core-modules/billing/types/billing-portal-checkout-session-parameters.type';
 import { formatBillingDatabaseProductToGraphqlDTO } from 'src/engine/core-modules/billing/utils/format-database-product-to-graphql-dto.util';
 import { FeatureFlagKey } from 'src/engine/core-modules/feature-flag/enums/feature-flag-key.enum';
 import { FeatureFlagService } from 'src/engine/core-modules/feature-flag/services/feature-flag.service';
@@ -84,42 +85,49 @@ export class BillingResolver {
         workspace.id,
       );
 
-    let productPrice;
+    const checkoutSessionParams: BillingPortalCheckoutSessionParameters = {
+      user,
+      workspace,
+      successUrlPath,
+      plan: plan ?? BillingPlanKey.PRO,
+      requirePaymentMethod,
+    };
 
     if (isBillingPlansEnabled) {
-      const baseProduct = await this.billingPlanService.getPlanBaseProduct(
-        plan ?? BillingPlanKey.PRO,
-      );
-
-      if (!baseProduct) {
-        throw new GraphQLError('Base product not found');
-      }
-
-      productPrice = baseProduct.billingPrices.find(
-        (price) => price.interval === recurringInterval,
-      );
-    } else {
-      productPrice = await this.stripePriceService.getStripePrice(
-        AvailableProduct.BasePlan,
-        recurringInterval,
-      );
+      const billingPricesPerPlan =
+        await this.billingPlanService.getPricesPerPlan({
+          planKey: checkoutSessionParams.plan,
+          interval: recurringInterval,
+        });
+      const checkoutSessionURL =
+        await this.billingPortalWorkspaceService.computeCheckoutSessionURL({
+          ...checkoutSessionParams,
+          billingPricesPerPlan,
+        });
+
+      return {
+        url: checkoutSessionURL,
+      };
     }
 
+    const productPrice = await this.stripePriceService.getStripePrice(
+      AvailableProduct.BasePlan,
+      recurringInterval,
+    );
+
     if (!productPrice) {
       throw new GraphQLError(
         'Product price not found for the given recurring interval',
       );
     }
+    const checkoutSessionURL =
+      await this.billingPortalWorkspaceService.computeCheckoutSessionURL({
+        ...checkoutSessionParams,
+        priceId: productPrice.stripePriceId,
+      });
 
     return {
-      url: await this.billingPortalWorkspaceService.computeCheckoutSessionURL(
-        user,
-        workspace,
-        productPrice.stripePriceId,
-        successUrlPath,
-        plan,
-        requirePaymentMethod,
-      ),
+      url: checkoutSessionURL,
     };
   }
 

packages/twenty-server/src/engine/core-modules/billing/services/billing-plan.service.ts

@@ -9,8 +9,10 @@ import {
 } from 'src/engine/core-modules/billing/billing.exception';
 import { BillingProduct } from 'src/engine/core-modules/billing/entities/billing-product.entity';
 import { BillingPlanKey } from 'src/engine/core-modules/billing/enums/billing-plan-key.enum';
+import { SubscriptionInterval } from 'src/engine/core-modules/billing/enums/billing-subscription-interval.enum';
 import { BillingUsageType } from 'src/engine/core-modules/billing/enums/billing-usage-type.enum';
 import { BillingGetPlanResult } from 'src/engine/core-modules/billing/types/billing-get-plan-result.type';
+import { BillingGetPricesPerPlanResult } from 'src/engine/core-modules/billing/types/billing-get-prices-per-plan-result.type';
 
 @Injectable()
 export class BillingPlanService {
@@ -104,4 +106,48 @@ export class BillingPlanService {
       };
     });
   }
+
+  async getPricesPerPlan({
+    planKey,
+    interval,
+  }: {
+    planKey: BillingPlanKey;
+    interval: SubscriptionInterval;
+  }): Promise<BillingGetPricesPerPlanResult> {
+    const plans = await this.getPlans();
+    const plan = plans.find((plan) => plan.planKey === planKey);
+
+    if (!plan) {
+      throw new BillingException(
+        'Billing plan not found',
+        BillingExceptionCode.BILLING_PLAN_NOT_FOUND,
+      );
+    }
+    const { baseProduct, meteredProducts, otherLicensedProducts } = plan;
+    const baseProductPrice = baseProduct.billingPrices.find(
+      (price) => price.interval === interval,
+    );
+
+    if (!baseProductPrice) {
+      throw new BillingException(
+        'Base product price not found for given interval',
+        BillingExceptionCode.BILLING_PRICE_NOT_FOUND,
+      );
+    }
+    const filterPricesByInterval = (product: BillingProduct) =>
+      product.billingPrices.filter((price) => price.interval === interval);
+
+    const meteredProductsPrices = meteredProducts.flatMap(
+      filterPricesByInterval,
+    );
+    const otherLicensedProductsPrices = otherLicensedProducts.flatMap(
+      filterPricesByInterval,
+    );
+
+    return {
+      baseProductPrice,
+      meteredProductsPrices,
+      otherLicensedProductsPrices,
+    };
+  }
 }

packages/twenty-server/src/engine/core-modules/billing/services/billing-portal.workspace-service.ts

@@ -2,16 +2,22 @@ import { Injectable, Logger } from '@nestjs/common';
 import { InjectRepository } from '@nestjs/typeorm';
 
 import { isDefined } from 'class-validator';
+import Stripe from 'stripe';
 import { Repository } from 'typeorm';
 
+import {
+  BillingException,
+  BillingExceptionCode,
+} from 'src/engine/core-modules/billing/billing.exception';
 import { BillingSubscription } from 'src/engine/core-modules/billing/entities/billing-subscription.entity';
-import { BillingPlanKey } from 'src/engine/core-modules/billing/enums/billing-plan-key.enum';
-import { BillingSubscriptionService } from 'src/engine/core-modules/billing/services/billing-subscription.service';
 import { StripeBillingPortalService } from 'src/engine/core-modules/billing/stripe/services/stripe-billing-portal.service';
 import { StripeCheckoutService } from 'src/engine/core-modules/billing/stripe/services/stripe-checkout.service';
+import { BillingGetPricesPerPlanResult } from 'src/engine/core-modules/billing/types/billing-get-prices-per-plan-result.type';
+import { BillingPortalCheckoutSessionParameters } from 'src/engine/core-modules/billing/types/billing-portal-checkout-session-parameters.type';
 import { DomainManagerService } from 'src/engine/core-modules/domain-manager/service/domain-manager.service';
+import { FeatureFlagKey } from 'src/engine/core-modules/feature-flag/enums/feature-flag-key.enum';
+import { FeatureFlagService } from 'src/engine/core-modules/feature-flag/services/feature-flag.service';
 import { UserWorkspace } from 'src/engine/core-modules/user-workspace/user-workspace.entity';
-import { User } from 'src/engine/core-modules/user/user.entity';
 import { Workspace } from 'src/engine/core-modules/workspace/workspace.entity';
 import { assert } from 'src/utils/assert';
 
@@ -22,21 +28,22 @@ export class BillingPortalWorkspaceService {
     private readonly stripeCheckoutService: StripeCheckoutService,
     private readonly stripeBillingPortalService: StripeBillingPortalService,
     private readonly domainManagerService: DomainManagerService,
+    private readonly featureFlagService: FeatureFlagService,
     @InjectRepository(BillingSubscription, 'core')
     private readonly billingSubscriptionRepository: Repository<BillingSubscription>,
     @InjectRepository(UserWorkspace, 'core')
     private readonly userWorkspaceRepository: Repository<UserWorkspace>,
-    private readonly billingSubscriptionService: BillingSubscriptionService,
   ) {}
 
-  async computeCheckoutSessionURL(
-    user: User,
-    workspace: Workspace,
-    priceId: string,
-    successUrlPath?: string,
-    plan?: BillingPlanKey,
-    requirePaymentMethod?: boolean,
-  ): Promise<string> {
+  async computeCheckoutSessionURL({
+    user,
+    workspace,
+    billingPricesPerPlan,
+    successUrlPath,
+    plan,
+    priceId,
+    requirePaymentMethod,
+  }: BillingPortalCheckoutSessionParameters): Promise<string> {
     const frontBaseUrl = this.domainManagerService.buildWorkspaceURL({
       subdomain: workspace.subdomain,
     });
@@ -56,23 +63,37 @@ export class BillingPortalWorkspaceService {
     });
 
     const stripeCustomerId = subscription?.stripeCustomerId;
+    const isBillingPlansEnabled =
+      await this.featureFlagService.isFeatureEnabled(
+        FeatureFlagKey.IsBillingPlansEnabled,
+        workspace.id,
+      );
 
-    const session = await this.stripeCheckoutService.createCheckoutSession({
-      user,
-      workspaceId: workspace.id,
-      priceId,
-      quantity,
-      successUrl,
-      cancelUrl,
-      stripeCustomerId,
-      plan,
-      requirePaymentMethod,
-      withTrialPeriod: !isDefined(subscription),
-    });
+    const stripeSubscriptionLineItems =
+      await this.getStripeSubscriptionLineItems({
+        quantity,
+        isBillingPlansEnabled,
+        billingPricesPerPlan,
+        priceId,
+      });
+
+    const checkoutSession =
+      await this.stripeCheckoutService.createCheckoutSession({
+        user,
+        workspaceId: workspace.id,
+        stripeSubscriptionLineItems,
+        successUrl,
+        cancelUrl,
+        stripeCustomerId,
+        plan,
+        requirePaymentMethod,
+        withTrialPeriod: !isDefined(subscription),
+        isBillingPlansEnabled,
+      });
 
-    assert(session.url, 'Error: missing checkout.session.url');
+    assert(checkoutSession.url, 'Error: missing checkout.session.url');
 
-    return session.url;
+    return checkoutSession.url;
   }
 
   async computeBillingPortalSessionURLOrThrow(
@@ -113,4 +134,39 @@ export class BillingPortalWorkspaceService {
 
     return session.url;
   }
+
+  private getStripeSubscriptionLineItems({
+    quantity,
+    isBillingPlansEnabled,
+    billingPricesPerPlan,
+    priceId,
+  }: {
+    quantity: number;
+    isBillingPlansEnabled: boolean;
+    billingPricesPerPlan?: BillingGetPricesPerPlanResult;
+    priceId?: string;
+  }): Stripe.Checkout.SessionCreateParams.LineItem[] {
+    if (isBillingPlansEnabled && billingPricesPerPlan) {
+      return [
+        {
+          price: billingPricesPerPlan.baseProductPrice.stripePriceId,
+          quantity,
+        },
+        ...billingPricesPerPlan.meteredProductsPrices.map((price) => ({
+          price: price.stripePriceId,
+        })),
+      ];
+    }
+
+    if (priceId && !isBillingPlansEnabled) {
+      return [{ price: priceId, quantity }];
+    }
+
+    throw new BillingException(
+      isBillingPlansEnabled
+        ? 'Missing Billing prices per plan'
+        : 'Missing price id',
+      BillingExceptionCode.BILLING_PRICE_NOT_FOUND,
+    );
+  }
 }

packages/twenty-server/src/engine/core-modules/billing/stripe/services/stripe-checkout.service.ts

@@ -27,33 +27,28 @@ export class StripeCheckoutService {
   async createCheckoutSession({
     user,
     workspaceId,
-    priceId,
-    quantity,
+    stripeSubscriptionLineItems,
     successUrl,
     cancelUrl,
     stripeCustomerId,
     plan = BillingPlanKey.PRO,
     requirePaymentMethod = true,
     withTrialPeriod,
+    isBillingPlansEnabled = false,
   }: {
     user: User;
     workspaceId: string;
-    priceId: string;
-    quantity: number;
+    stripeSubscriptionLineItems: Stripe.Checkout.SessionCreateParams.LineItem[];
     successUrl?: string;
     cancelUrl?: string;
     stripeCustomerId?: string;
     plan?: BillingPlanKey;
     requirePaymentMethod?: boolean;
     withTrialPeriod: boolean;
+    isBillingPlansEnabled: boolean;
   }): Promise<Stripe.Checkout.Session> {
     return await this.stripe.checkout.sessions.create({
-      line_items: [
-        {
-          price: priceId,
-          quantity,
-        },
-      ],
+      line_items: stripeSubscriptionLineItems,
       mode: 'subscription',
       subscription_data: {
         metadata: {
@@ -68,7 +63,11 @@ export class StripeCheckoutService {
                   : 'BILLING_FREE_TRIAL_WITHOUT_CREDIT_CARD_DURATION_IN_DAYS',
               ),
               trial_settings: {
-                end_behavior: { missing_payment_method: 'pause' },
+                end_behavior: {
+                  missing_payment_method: isBillingPlansEnabled
+                    ? 'create_invoice'
+                    : 'pause',
+                },
               },
             }
           : {}),

packages/twenty-server/src/engine/core-modules/billing/types/billing-get-prices-per-plan-result.type.ts

@@ -0,0 +1,7 @@
+import { BillingPrice } from 'src/engine/core-modules/billing/entities/billing-price.entity';
+
+export type BillingGetPricesPerPlanResult = {
+  baseProductPrice: BillingPrice;
+  meteredProductsPrices: BillingPrice[];
+  otherLicensedProductsPrices: BillingPrice[];
+};

packages/twenty-server/src/engine/core-modules/billing/types/billing-portal-checkout-session-parameters.type.ts

@@ -0,0 +1,14 @@
+import { BillingPlanKey } from 'src/engine/core-modules/billing/enums/billing-plan-key.enum';
+import { BillingGetPricesPerPlanResult } from 'src/engine/core-modules/billing/types/billing-get-prices-per-plan-result.type';
+import { User } from 'src/engine/core-modules/user/user.entity';
+import { Workspace } from 'src/engine/core-modules/workspace/workspace.entity';
+
+export type BillingPortalCheckoutSessionParameters = {
+  user: User;
+  workspace: Workspace;
+  billingPricesPerPlan?: BillingGetPricesPerPlanResult;
+  successUrlPath?: string;
+  plan: BillingPlanKey;
+  priceId?: string;
+  requirePaymentMethod?: boolean;
+};