> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dodopayments.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Vercel Functions

> 将 DodoPayments Webhook 部署到 Vercel

<Card title="GitHub Repository" icon="github" href="https://github.com/dodopayments/cloud-functions/tree/main/vercel">
  完整的源代码与设置指南
</Card>

## 快速设置

### 1. 先决条件

* [Vercel 账户](https://vercel.com/signup)
* [Neon 数据库](https://neon.com) 账户
* 从 [仪表板](https://app.dodopayments.com/) 获取 DodoPayments API 密钥

### 2. 安装依赖

```bash theme={null}
npm install -g vercel
vercel login
git clone https://github.com/dodopayments/cloud-functions.git
cd cloud-functions/vercel
npm install
```

### 3. 数据库设置

1. 在 [Neon](https://neon.com) 注册
2. 创建一个新项目
3. 打开 SQL 编辑器
4. 复制并粘贴 [`schema.sql`](#database-schema) 中的内容
5. 运行查询
6. 从 Neon → Connection Details 获取连接字符串

### 4. 设置初始环境变量

通过 Vercel CLI：

```bash theme={null}
vercel env add DATABASE_URL
vercel env add DODO_PAYMENTS_API_KEY
```

> **注意：** 一旦部署完成并拥有 webhook URL，我们将设置 `DODO_PAYMENTS_WEBHOOK_KEY`。

### 5. 部署

```bash theme={null}
npm run deploy
```

### 6. 获取您的 Webhook URL

您的 Webhook URL 是：

```
https://[your-project].vercel.app/api/webhook
```

### 7. 在 DodoPayments 仪表板中注册 Webhook

1. 进入 [DodoPayments Dashboard](https://app.dodopayments.com) → Developer → Webhooks
2. 创建新的 webhook 端点
3. 将你的 webhook URL 配置为该端点
4. 启用以下订阅事件：
   * `subscription.active`
   * `subscription.cancelled`
   * `subscription.renewed`
5. 复制 **Signing Secret**

### 8. 设置 Webhook 密钥并重新部署

```bash theme={null}
vercel env add DODO_PAYMENTS_WEBHOOK_KEY
npm run deploy
```

## 它的功能

处理订阅事件并将其存储在 PostgreSQL 中：

* **subscription.active** - 创建/更新客户和订阅记录
* **subscription.cancelled** - 将订阅标记为已取消
* **subscription.renewed** - 更新下一个账单日期

## 主要特性

✅ **Signature verification** - 使用 dodopayments 库\
✅ **Idempotency** - 使用 webhook ID 防止重复处理\
✅ **Event logging** - 在 `webhook_events` 表中保留完整审计日志\
✅ **Error handling** - 记录并支持重试

> **注意：** 此实现演示了如何处理三类核心订阅事件（`subscription.active`、`subscription.cancelled`、`subscription.renewed`）并使用最少字段。你可以根据需求轻松扩展以支持更多事件类型和字段。

## 配置文件

<CodeGroup>
  ```json package.json theme={null}
  {
    "name": "dodo-webhook-vercel",
    "version": "1.0.0",
    "type": "module",
    "description": "DodoPayments Webhook Handler for Vercel",
    "scripts": {
      "start": "vercel dev",
      "deploy": "vercel --prod"
    },
    "dependencies": {
      "@neondatabase/serverless": "^1.0.2",
      "dodopayments": "^2.4.1"
    },
    "devDependencies": {
      "typescript": "^5.9.3",
      "vercel": "^48.4.1"
    }
  }
  ```

  ```json tsconfig.json theme={null}
  {
    "compilerOptions": {
      "target": "ES2022",
      "module": "ES2022",
      "lib": ["ES2022"],
      "moduleResolution": "node",
      "esModuleInterop": true,
      "strict": true,
      "skipLibCheck": true,
      "resolveJsonModule": true,
      "allowSyntheticDefaultImports": true,
      "forceConsistentCasingInFileNames": true,
      "isolatedModules": true,
      "types": ["node"]
    },
    "include": ["api/**/*.ts"],
    "exclude": ["node_modules"]
  }
  ```
</CodeGroup>

## 数据库架构

<CodeGroup>
  ```sql schema.sql expandable theme={null}
  -- DodoPayments Webhook Database Schema
  -- Compatible with PostgreSQL (Supabase, Neon, etc.)

  -- Enable UUID extension (if not already enabled)
  CREATE EXTENSION IF NOT EXISTS "uuid-ossp";

  -- Customers table
  CREATE TABLE IF NOT EXISTS customers (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    email TEXT NOT NULL,
    name TEXT NOT NULL,
    dodo_customer_id TEXT UNIQUE NOT NULL,
    created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
    updated_at TIMESTAMP WITH TIME ZONE DEFAULT NOW()
  );

  -- Subscriptions table
  CREATE TABLE IF NOT EXISTS subscriptions (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    customer_id UUID NOT NULL REFERENCES customers(id) ON DELETE CASCADE,
    dodo_subscription_id TEXT UNIQUE NOT NULL,
    product_id TEXT NOT NULL,
    status TEXT NOT NULL CHECK (status IN ('pending', 'active', 'on_hold', 'cancelled', 'failed', 'expired')),
    billing_interval TEXT NOT NULL CHECK (billing_interval IN ('day', 'week', 'month', 'year')),
    amount INTEGER NOT NULL,
    currency TEXT NOT NULL,
    next_billing_date TIMESTAMP WITH TIME ZONE NOT NULL,
    cancelled_at TIMESTAMP WITH TIME ZONE,
    created_at TIMESTAMP WITH TIME ZONE NOT NULL,
    updated_at TIMESTAMP WITH TIME ZONE DEFAULT NOW()
  );

  -- Webhook events log
  CREATE TABLE IF NOT EXISTS webhook_events (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    webhook_id TEXT UNIQUE,
    event_type TEXT NOT NULL,
    data JSONB NOT NULL,
    processed BOOLEAN DEFAULT FALSE,
    error_message TEXT,
    created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
    processed_at TIMESTAMP WITH TIME ZONE,
    attempts INTEGER DEFAULT 0
  );

  -- Indexes for better query performance
  CREATE INDEX IF NOT EXISTS idx_customers_email ON customers(email);
  CREATE INDEX IF NOT EXISTS idx_customers_dodo_id ON customers(dodo_customer_id);
  CREATE INDEX IF NOT EXISTS idx_subscriptions_dodo_id ON subscriptions(dodo_subscription_id);
  CREATE INDEX IF NOT EXISTS idx_subscriptions_customer_id ON subscriptions(customer_id);
  CREATE INDEX IF NOT EXISTS idx_subscriptions_status ON subscriptions(status);
  CREATE INDEX IF NOT EXISTS idx_webhook_events_processed ON webhook_events(processed, created_at);
  CREATE INDEX IF NOT EXISTS idx_webhook_events_type ON webhook_events(event_type);
  CREATE INDEX IF NOT EXISTS idx_webhook_events_created_at ON webhook_events(created_at DESC);
  CREATE INDEX IF NOT EXISTS idx_webhook_events_webhook_id ON webhook_events(webhook_id);

  -- Function to automatically update updated_at timestamp
  CREATE OR REPLACE FUNCTION update_updated_at_column()
  RETURNS TRIGGER AS $$
  BEGIN
    NEW.updated_at = NOW();
    RETURN NEW;
  END;
  $$ LANGUAGE plpgsql;

  -- Triggers to automatically update updated_at
  CREATE TRIGGER update_customers_updated_at
    BEFORE UPDATE ON customers
    FOR EACH ROW
    EXECUTE FUNCTION update_updated_at_column();

  CREATE TRIGGER update_subscriptions_updated_at
    BEFORE UPDATE ON subscriptions
    FOR EACH ROW
    EXECUTE FUNCTION update_updated_at_column();

  -- Comments for documentation
  COMMENT ON TABLE customers IS 'Stores customer information from DodoPayments';
  COMMENT ON TABLE subscriptions IS 'Stores subscription data from DodoPayments';
  COMMENT ON TABLE webhook_events IS 'Logs all incoming webhook events for audit and retry purposes';

  COMMENT ON COLUMN customers.dodo_customer_id IS 'Unique customer ID from DodoPayments';
  COMMENT ON COLUMN subscriptions.dodo_subscription_id IS 'Unique subscription ID from DodoPayments';
  COMMENT ON COLUMN subscriptions.amount IS 'Amount in smallest currency unit (e.g., cents)';
  COMMENT ON COLUMN subscriptions.currency IS 'Currency used for the subscription payments (e.g., USD, EUR, INR)';
  COMMENT ON COLUMN webhook_events.attempts IS 'Number of processing attempts for failed webhooks';
  COMMENT ON COLUMN webhook_events.data IS 'Full webhook payload as JSON';
  ```
</CodeGroup>

**创建的表：**

* **customers** - 电子邮件，姓名，dodo\_customer\_id
* **subscriptions** - 状态，金额，下一个账单日期，链接到客户
* **webhook\_events** - 带有幂等性的 webhook\_id 的事件日志

## 实现代码

<CodeGroup>
  ```typescript api/webhook/index.ts expandable theme={null}
  import { neon, NeonQueryFunction } from '@neondatabase/serverless';
  import { DodoPayments } from 'dodopayments';

  interface WebhookPayload {
    business_id: string;
    type: string;
    timestamp: string;
    data: {
      payload_type:
        | "Payment"
        | "Subscription"
        | "Refund"
        | "Dispute"
        | "LicenseKey"
        | "CreditLedgerEntry"
        | "CreditBalanceLow"
        | "AbandonedCheckout"
        | "DunningAttempt"
        | "EntitlementGrant";
      subscription_id: string;
      customer: {
        customer_id: string;
        email: string;
        name: string;
      };
      product_id: string;
      status: string;
      recurring_pre_tax_amount: number;
      payment_frequency_interval: string;
      created_at: string;
      next_billing_date: string;
      cancelled_at?: string | null;
      currency: string;
    };
  }

  // Disable body parsing to access raw body for webhook verification
  export const config = {
    api: {
      bodyParser: false,
    },
  };

  const corsHeaders = {
    'Access-Control-Allow-Origin': '*',
    'Access-Control-Allow-Headers': 'authorization, x-client-info, apikey, content-type, webhook-id, webhook-signature, webhook-timestamp',
    'Access-Control-Allow-Methods': 'POST, OPTIONS',
  };

  // Helper function for JSON responses
  function jsonResponse(data: unknown, status: number = 200) {
    return new Response(JSON.stringify(data), {
      status,
      headers: { ...corsHeaders, 'Content-Type': 'application/json' }
    });
  }

  // Handle subscription events
  async function handleSubscriptionEvent(sql: NeonQueryFunction<false, false>, payload: WebhookPayload, status: string) {
    if (!payload.data.customer.customer_id || !payload.data.subscription_id) {
      throw new Error('Missing required fields: customer_id or subscription_id');
    }

    console.log('🔄 Processing subscription event:', JSON.stringify(payload, null, 2));

    const customer = payload.data.customer;

    // Upsert customer (create if doesn't exist, otherwise use existing)
    const customerResult = await sql`
      INSERT INTO customers (email, name, dodo_customer_id, created_at)
      VALUES (${customer.email}, ${customer.name}, ${customer.customer_id}, ${new Date().toISOString()})
      ON CONFLICT (dodo_customer_id) 
      DO UPDATE SET 
        email = EXCLUDED.email,
        name = EXCLUDED.name,
        updated_at = ${new Date().toISOString()}
      RETURNING id
    `;

    const customerId = customerResult[0].id;
    console.log(`✅ Customer upserted with ID: ${customerId}`);

    // Upsert subscription
    await sql`
      INSERT INTO subscriptions (
        customer_id, dodo_subscription_id, product_id, status, 
        billing_interval, amount, currency, created_at, next_billing_date, cancelled_at, updated_at
      )
      VALUES (
        ${customerId}, ${payload.data.subscription_id},
        ${payload.data.product_id}, ${status},
        ${payload.data.payment_frequency_interval.toLowerCase()}, ${payload.data.recurring_pre_tax_amount},
        ${payload.data.currency}, ${payload.data.created_at}, ${payload.data.next_billing_date},
        ${payload.data.cancelled_at ?? null}, ${new Date().toISOString()}
      )
      ON CONFLICT (dodo_subscription_id) 
      DO UPDATE SET 
        customer_id = EXCLUDED.customer_id,
        product_id = EXCLUDED.product_id,
        status = EXCLUDED.status,
        billing_interval = EXCLUDED.billing_interval,
        amount = EXCLUDED.amount,
        currency = EXCLUDED.currency,
        created_at = EXCLUDED.created_at,
        next_billing_date = EXCLUDED.next_billing_date,
        cancelled_at = EXCLUDED.cancelled_at,
        updated_at = EXCLUDED.updated_at
    `;

    console.log(`✅ Subscription upserted with ${status} status`)
  }

  // Handle CORS preflight
  export async function OPTIONS() {
    return new Response('ok', { 
      status: 200,
      headers: corsHeaders 
    });
  }

  // Handle webhook POST request
  export async function POST(req: Request) {
    try {
      // Get raw body for webhook signature verification
      const rawBody = await req.text();
      
      console.log('📨 Webhook received');

      const DATABASE_URL = process.env.DATABASE_URL;
      const API_KEY = process.env.DODO_PAYMENTS_API_KEY;
      const WEBHOOK_KEY = process.env.DODO_PAYMENTS_WEBHOOK_KEY;

      if (!DATABASE_URL) {
        console.error('❌ Missing DATABASE_URL environment variable');
        return jsonResponse({ error: 'Server configuration error' }, 500);
      }

      // Verify required environment variables
      if (!API_KEY) {
        console.error('❌ DODO_PAYMENTS_API_KEY is not configured');
        return jsonResponse({ error: 'API key not configured' }, 500);
      }

      if (!WEBHOOK_KEY) {
        console.error('❌ DODO_PAYMENTS_WEBHOOK_KEY is not configured');
        return jsonResponse({ error: 'Webhook verification key not configured' }, 500);
      }

      // Verify webhook signature (required for security)
      const webhookHeaders = {
        'webhook-id': req.headers.get('webhook-id') || '',
        'webhook-signature': req.headers.get('webhook-signature') || '',
        'webhook-timestamp': req.headers.get('webhook-timestamp') || '',
      };

      try {
        const dodoPaymentsClient = new DodoPayments({
          bearerToken: API_KEY,
          webhookKey: WEBHOOK_KEY,
        });
        const unwrappedWebhook = dodoPaymentsClient.webhooks.unwrap(rawBody, { headers: webhookHeaders });
        console.log('Unwrapped webhook:', unwrappedWebhook);
        console.log('✅ Webhook signature verified');
      } catch (error) {
        console.error('❌ Webhook verification failed:', error);
        return jsonResponse({ error: 'Webhook verification failed' }, 401);
      }

      // Initialize Neon client
      const sql = neon(DATABASE_URL);

      const payload: WebhookPayload = JSON.parse(rawBody);
      const eventType = payload.type;
      const eventData = payload.data;
      const webhookId = req.headers.get('webhook-id') || '';

      console.log(`📋 Webhook payload:`, JSON.stringify(payload, null, 2));

      // Check for duplicate webhook-id (idempotency)
      if (webhookId) {
        const existingEvent = await sql`
          SELECT id FROM webhook_events WHERE webhook_id = ${webhookId}
        `;

        if (existingEvent.length > 0) {
          console.log(`⚠️ Webhook ${webhookId} already processed, skipping (idempotency)`);
          return jsonResponse({ success: true, message: 'Webhook already processed' });
        }
      }

      // Log webhook event with webhook_id for idempotency
      const logResult = await sql`
        INSERT INTO webhook_events (webhook_id, event_type, data, processed, created_at)
        VALUES (${webhookId || null}, ${eventType}, ${JSON.stringify(eventData)}, ${false}, ${new Date().toISOString()})
        RETURNING id
      `;

      const loggedEventId = logResult[0].id;
      console.log('📝 Webhook event logged with ID:', loggedEventId);

      console.log(`🔄 Processing: ${eventType} (${eventData.payload_type || 'unknown payload type'})`);

      try {
        switch (eventType) {
          case 'subscription.active':
            await handleSubscriptionEvent(sql, payload, 'active');
            break;
          case 'subscription.cancelled':
            await handleSubscriptionEvent(sql, payload, 'cancelled');
            break;
          case 'subscription.renewed':
            console.log('🔄 Subscription renewed - keeping active status and updating billing date');
            await handleSubscriptionEvent(sql, payload, 'active');
            break;
          default:
            console.log(`ℹ️ Event ${eventType} logged but not processed (no handler available)`);
        }

        await sql`
          UPDATE webhook_events 
          SET processed = ${true}, processed_at = ${new Date().toISOString()}
          WHERE id = ${loggedEventId}
        `;

        console.log('✅ Webhook marked as processed');
      } catch (processingError) {
        console.error('❌ Error processing webhook event:', processingError);

        await sql`
          UPDATE webhook_events 
          SET processed = ${false}, 
              error_message = ${processingError instanceof Error ? processingError.message : 'Unknown error'},
              processed_at = ${new Date().toISOString()}
          WHERE id = ${loggedEventId}
        `;

        throw processingError;
      }

      console.log('✅ Webhook processed successfully');

      return jsonResponse({
        success: true,
        event_type: eventType,
        event_id: loggedEventId
      });

    } catch (error) {
      console.error('❌ Webhook processing failed:', error);
      return jsonResponse({
        error: 'Webhook processing failed',
        details: error instanceof Error ? error.message : 'Unknown error'
      }, 500);
    }
  }
  ```
</CodeGroup>

## 工作原理

Webhook 处理器：

1. **禁用正文解析** - 以便访问原始正文用于签名验证
2. **验证签名** - 使用 HMAC-SHA256 确保请求来自 DodoPayments
3. **检查重复** - 使用 webhook ID 防止重复处理同一事件
4. **记录事件** - 将原始 webhook 存入 `webhook_events` 表以保持审计跟踪
5. **处理事件** - 在 Neon 中创建或更新客户与订阅
6. **处理错误** - 记录失败并将事件标记为未处理以便重试

## 测试

**本地开发：**

```bash theme={null}
npm start
```

**在 Vercel 仪表板中查看日志：**

1. 选择您的项目
2. 转到 **部署** → 最新部署
3. 点击 **函数** → **日志**

**在 DodoPayments 仪表板中配置：**

1. 转到开发者 → Webhooks
2. 添加端点，使用您的 Vercel Functions URL
3. 启用：subscription.active, subscription.cancelled, subscription.renewed

## 常见问题

| 问题      | 解决方案                                 |
| ------- | ------------------------------------ |
| 验证失败    | 检查 DodoPayments 仪表板中的 Webhook 密钥是否正确 |
| 数据库连接错误 | 验证 Neon 连接字符串并使用池化连接                 |
| 函数超时    | 优化查询；专业计划有更长的超时（60s）                 |
| 环境变量不可用 | 在仪表板或 CLI 中设置，确保选择所有环境，重新部署          |

## 资源

* [Vercel Functions 文档](https://vercel.com/docs/functions)
* [Vercel CLI](https://vercel.com/docs/cli)
* [Neon 文档](https://neon.com/docs/)
* [Webhook 事件指南](/developer-resources/webhooks/intents/webhook-events-guide)
* [GitHub 仓库](https://github.com/dodopayments/cloud-functions/tree/main/vercel)