Implement updateSubscription feature and refactor billing services

This commit introduces the updateSubscription method to the BillingStrategyProviderService, ensuring that subscriptions can be updated within the billing core. Additionally, a refactor has been applied to the BillingGatewayFactoryService and stripe-billing-strategy.service to improve error handling and the robustness of subscription updates. Logging in the webhook route has been adjusted for clarity and the data model has been enhanced.

packages/billing/core/src/create-billing-schema.ts

@@ -103,6 +103,34 @@ export const PlanSchema = z
       message: 'Line item IDs must be unique',
       path: ['lineItems'],
     },
+  )
+  .refine(
+    (data) => {
+      if (data.paymentType === 'one-time') {
+        const meteredItems = data.lineItems.filter(
+          (item) => item.type === 'metered',
+        );
+
+        return meteredItems.length === 0;
+      }
+    },
+    {
+      message: 'One-time plans must not have metered line items',
+      path: ['paymentType', 'lineItems'],
+    },
+  )
+  .refine(
+    (data) => {
+      if (data.paymentType === 'one-time') {
+        const baseItems = data.lineItems.filter((item) => item.type !== 'base');
+
+        return baseItems.length === 0;
+      }
+    },
+    {
+      message: 'One-time plans must not have non-base line items',
+      path: ['paymentType', 'lineItems'],
+    },
   );
 
 const ProductSchema = z
@@ -259,3 +287,20 @@ export function getProductPlanPairByVariantId(
 
   throw new Error('Plan not found');
 }
+
+export function getLineItemTypeById(
+  config: z.infer<typeof BillingSchema>,
+  id: string,
+) {
+  for (const product of config.products) {
+    for (const plan of product.plans) {
+      for (const lineItem of plan.lineItems) {
+        if (lineItem.type === id) {
+          return lineItem.type;
+        }
+      }
+    }
+  }
+
+  throw new Error(`Line Item with ID ${id} not found`);
+}

packages/billing/core/src/schema/index.ts

@@ -3,3 +3,4 @@ export * from './create-biling-portal-session.schema';
 export * from './retrieve-checkout-session.schema';
 export * from './cancel-subscription-params.schema';
 export * from './report-billing-usage.schema';
+export * from './update-subscription-params.schema';

packages/billing/core/src/schema/update-subscription-params.schema.ts

@@ -0,0 +1,7 @@
+import { z } from 'zod';
+
+export const UpdateSubscriptionParamsSchema = z.object({
+  subscriptionId: z.string().min(1),
+  subscriptionItemId: z.string().min(1),
+  quantity: z.number().min(1),
+});

packages/billing/core/src/services/billing-strategy-provider.service.ts

@@ -4,9 +4,10 @@ import {
   CancelSubscriptionParamsSchema,
   CreateBillingCheckoutSchema,
   CreateBillingPortalSessionSchema,
+  ReportBillingUsageSchema,
   RetrieveCheckoutSessionSchema,
+  UpdateSubscriptionParamsSchema,
 } from '../schema';
-import { ReportBillingUsageSchema } from '../schema';
 
 export abstract class BillingStrategyProviderService {
   abstract createBillingPortalSession(
@@ -44,4 +45,10 @@ export abstract class BillingStrategyProviderService {
   ): Promise<{
     success: boolean;
   }>;
+
+  abstract updateSubscription(
+    params: z.infer<typeof UpdateSubscriptionParamsSchema>,
+  ): Promise<{
+    success: boolean;
+  }>;
 }

packages/billing/gateway/src/server/services/billing-event-handler/billing-event-handler.service.ts

@@ -154,7 +154,7 @@ export class BillingEventHandlerService {
 
         Logger.info(
           {
-            namespace: 'billing',
+            namespace: this.namespace,
             sessionId,
           },
           'Successfully updated payment status',

packages/billing/gateway/src/server/services/billing-event-handler/billing-gateway-factory.service.ts

@@ -1,6 +1,7 @@
 import { z } from 'zod';
 
 import {
+  BillingConfig,
   BillingProviderSchema,
   BillingWebhookHandlerService,
 } from '@kit/billing';
@@ -8,12 +9,13 @@ import {
 export class BillingEventHandlerFactoryService {
   static async GetProviderStrategy(
     provider: z.infer<typeof BillingProviderSchema>,
+    config: BillingConfig,
   ): Promise<BillingWebhookHandlerService> {
     switch (provider) {
       case 'stripe': {
         const { StripeWebhookHandlerService } = await import('@kit/stripe');
 
-        return new StripeWebhookHandlerService();
+        return new StripeWebhookHandlerService(config);
       }
 
       case 'lemon-squeezy': {
@@ -21,7 +23,7 @@ export class BillingEventHandlerFactoryService {
           '@kit/lemon-squeezy'
         );
 
-        return new LemonSqueezyWebhookHandlerService();
+        return new LemonSqueezyWebhookHandlerService(config);
       }
 
       case 'paddle': {

packages/billing/gateway/src/server/services/billing-event-handler/billing-gateway-provider-factory.ts

@@ -1,3 +1,4 @@
+import { BillingConfig } from '@kit/billing';
 import { Database } from '@kit/supabase/database';
 import { getSupabaseServerActionClient } from '@kit/supabase/server-actions-client';
 
@@ -12,9 +13,12 @@ import { BillingEventHandlerFactoryService } from './billing-gateway-factory.ser
 export async function getBillingEventHandlerService(
   clientProvider: () => ReturnType<typeof getSupabaseServerActionClient>,
   provider: Database['public']['Enums']['billing_provider'],
+  config: BillingConfig,
 ) {
-  const strategy =
-    await BillingEventHandlerFactoryService.GetProviderStrategy(provider);
+  const strategy = await BillingEventHandlerFactoryService.GetProviderStrategy(
+    provider,
+    config,
+  );
 
   return new BillingEventHandlerService(clientProvider, strategy);
 }

packages/billing/gateway/src/server/services/billing-gateway/billing-gateway.service.ts

@@ -5,7 +5,9 @@ import {
   CancelSubscriptionParamsSchema,
   CreateBillingCheckoutSchema,
   CreateBillingPortalSessionSchema,
+  ReportBillingUsageSchema,
   RetrieveCheckoutSessionSchema,
+  UpdateSubscriptionParamsSchema,
 } from '@kit/billing/schema';
 
 import { BillingGatewayFactoryService } from './billing-gateway-factory.service';
@@ -92,4 +94,35 @@ export class BillingGatewayService {
 
     return strategy.cancelSubscription(payload);
   }
+
+  /**
+   * Reports the usage of the billing.
+   * @description This is used to report the usage of the billing to the provider.
+   * @param params
+   */
+  async reportUsage(params: z.infer<typeof ReportBillingUsageSchema>) {
+    const strategy = await BillingGatewayFactoryService.GetProviderStrategy(
+      this.provider,
+    );
+
+    const payload = ReportBillingUsageSchema.parse(params);
+
+    return strategy.reportUsage(payload);
+  }
+
+  /**
+   * Updates a subscription with the specified parameters.
+   * @param params
+   */
+  async updateSubscriptionItem(
+    params: z.infer<typeof UpdateSubscriptionParamsSchema>,
+  ) {
+    const strategy = await BillingGatewayFactoryService.GetProviderStrategy(
+      this.provider,
+    );
+
+    const payload = UpdateSubscriptionParamsSchema.parse(params);
+
+    return strategy.updateSubscription(payload);
+  }
 }

packages/billing/lemon-squeezy/src/services/lemon-squeezy-billing-strategy.service.ts

@@ -2,6 +2,7 @@ import {
   cancelSubscription,
   createUsageRecord,
   getCheckout,
+  updateSubscriptionItem,
 } from '@lemonsqueezy/lemonsqueezy.js';
 import 'server-only';
 import { z } from 'zod';
@@ -13,6 +14,7 @@ import {
   CreateBillingPortalSessionSchema,
   ReportBillingUsageSchema,
   RetrieveCheckoutSessionSchema,
+  UpdateSubscriptionParamsSchema,
 } from '@kit/billing/schema';
 import { Logger } from '@kit/shared/logger';
 
@@ -240,4 +242,35 @@ export class LemonSqueezyBillingStrategyService
 
     return { success: true };
   }
+
+  async updateSubscription(
+    params: z.infer<typeof UpdateSubscriptionParamsSchema>,
+  ) {
+    const ctx = {
+      name: 'billing.lemon-squeezy',
+      ...params,
+    };
+
+    Logger.info(ctx, 'Updating subscription...');
+
+    const { error } = await updateSubscriptionItem(params.subscriptionItemId, {
+      quantity: params.quantity,
+    });
+
+    if (error) {
+      Logger.error(
+        {
+          ...ctx,
+          error,
+        },
+        'Failed to update subscription',
+      );
+
+      throw error;
+    }
+
+    Logger.info(ctx, 'Subscription updated successfully');
+
+    return { success: true };
+  }
 }

packages/billing/lemon-squeezy/src/services/lemon-squeezy-webhook-handler.service.ts

@@ -1,7 +1,11 @@
 import { getOrder, getVariant } from '@lemonsqueezy/lemonsqueezy.js';
 import { createHmac, timingSafeEqual } from 'crypto';
 
-import { BillingWebhookHandlerService } from '@kit/billing';
+import {
+  BillingConfig,
+  BillingWebhookHandlerService,
+  getLineItemTypeById,
+} from '@kit/billing';
 import { Logger } from '@kit/shared/logger';
 import { Database } from '@kit/supabase/database';
 
@@ -35,6 +39,8 @@ export class LemonSqueezyWebhookHandlerService
 
   private readonly namespace = 'billing.lemon-squeezy';
 
+  constructor(private readonly config: BillingConfig) {}
+
   /**
    * @description Verifies the webhook signature - should throw an error if the signature is invalid
    */
@@ -307,6 +313,7 @@ export class LemonSqueezyWebhookHandlerService
         product_id: item.product,
         variant_id: item.variant,
         price_amount: item.unitAmount,
+        type: getLineItemTypeById(this.config, item.id),
       };
     });
 

packages/billing/stripe/src/services/stripe-billing-strategy.service.ts

@@ -9,6 +9,7 @@ import {
   CreateBillingPortalSessionSchema,
   ReportBillingUsageSchema,
   RetrieveCheckoutSessionSchema,
+  UpdateSubscriptionParamsSchema,
 } from '@kit/billing/schema';
 import { Logger } from '@kit/shared/logger';
 
@@ -198,6 +199,52 @@ export class StripeBillingStrategyService
     return { success: true };
   }
 
+  async updateSubscription(
+    params: z.infer<typeof UpdateSubscriptionParamsSchema>,
+  ) {
+    const stripe = await this.stripeProvider();
+
+    Logger.info(
+      {
+        name: 'billing.stripe',
+        ...params,
+      },
+      'Updating subscription...',
+    );
+
+    try {
+      await stripe.subscriptions.update(params.subscriptionId, {
+        items: [
+          {
+            id: params.subscriptionItemId,
+            quantity: params.quantity,
+          },
+        ],
+      });
+
+      Logger.info(
+        {
+          name: 'billing.stripe',
+          ...params,
+        },
+        'Subscription updated successfully',
+      );
+
+      return { success: true };
+    } catch (e) {
+      Logger.error(
+        {
+          name: 'billing.stripe',
+          ...params,
+          error: e,
+        },
+        'Failed to update subscription',
+      );
+
+      throw new Error('Failed to update subscription');
+    }
+  }
+
   private async stripeProvider(): Promise<Stripe> {
     return createStripeClient();
   }

packages/billing/stripe/src/services/stripe-webhook-handler.service.ts

@@ -1,6 +1,10 @@
 import Stripe from 'stripe';
 
-import { BillingWebhookHandlerService } from '@kit/billing';
+import {
+  BillingConfig,
+  BillingWebhookHandlerService,
+  getLineItemTypeById,
+} from '@kit/billing';
 import { Logger } from '@kit/shared/logger';
 import { Database } from '@kit/supabase/database';
 
@@ -18,6 +22,8 @@ export class StripeWebhookHandlerService
 {
   private stripe: Stripe | undefined;
 
+  constructor(private readonly config: BillingConfig) {}
+
   private readonly provider: Database['public']['Enums']['billing_provider'] =
     'stripe';
 
@@ -134,6 +140,8 @@ export class StripeWebhookHandlerService
     const accountId = session.client_reference_id!;
     const customerId = session.customer as string;
 
+    // if it's a subscription, we need to retrieve the subscription
+    // and build the payload for the subscription
     if (isSubscription) {
       const subscriptionId = session.subscription as string;
       const subscription = await stripe.subscriptions.retrieve(subscriptionId);
@@ -154,8 +162,10 @@ export class StripeWebhookHandlerService
 
       return onCheckoutCompletedCallback(payload);
     } else {
+      // if it's a one-time payment, we need to retrieve the session
       const sessionId = event.data.object.id;
 
+      // from the session, we need to retrieve the line items
       const sessionWithLineItems = await stripe.checkout.sessions.retrieve(
         event.data.object.id,
         {
@@ -280,6 +290,7 @@ export class StripeWebhookHandlerService
         price_amount: item.price?.unit_amount,
         interval: item.price?.recurring?.interval as string,
         interval_count: item.price?.recurring?.interval_count as number,
+        type: getLineItemTypeById(this.config, item.id),
       };
     });