feat: add Vercel serverless adapter for NestJS

api/index.ts

@@ -0,0 +1,66 @@
+import { NestFactory } from '@nestjs/core';
+import { ExpressAdapter } from '@nestjs/platform-express';
+import { AppModule } from '../dist/app.module';
+import { ValidationPipe } from '@nestjs/common';
+import { DocumentBuilder, SwaggerModule } from '@nestjs/swagger';
+import * as express from 'express';
+
+// 缓存 app 实例，避免每次冷启动都重新创建
+let cachedApp: any;
+
+async function bootstrap() {
+  if (!cachedApp) {
+    const expressApp = express();
+    const app = await NestFactory.create(
+      AppModule,
+      new ExpressAdapter(expressApp),
+    );
+
+    // 配置 CORS
+    app.enableCors({
+      origin: [
+        'https://tradingadvfrontend.vercel.app',
+        'http://localhost:8000',
+        'http://localhost:3030',
+      ],
+      credentials: true,
+      methods: ['GET', 'POST', 'PUT', 'DELETE', 'PATCH', 'OPTIONS'],
+      allowedHeaders: [
+        'Content-Type',
+        'Authorization',
+        'Accept',
+        'Origin',
+        'Referer',
+        'User-Agent',
+      ],
+    });
+
+    // 全局验证管道
+    app.useGlobalPipes(
+      new ValidationPipe({
+        whitelist: true,
+        forbidNonWhitelisted: true,
+        transform: true,
+      }),
+    );
+
+    // Swagger 文档
+    const config = new DocumentBuilder()
+      .setTitle('API 文档')
+      .setVersion('1.0')
+      .addBearerAuth()
+      .build();
+    const document = SwaggerModule.createDocument(app, config);
+    SwaggerModule.setup('api', app, document);
+
+    await app.init();
+    cachedApp = expressApp;
+  }
+  return cachedApp;
+}
+
+// Vercel Serverless handler
+export default async function handler(req: any, res: any) {
+  const app = await bootstrap();
+  app(req, res);
+}

vercel.json

@@ -2,14 +2,14 @@
   "version": 2,
   "builds": [
     {
-      "src": "dist/main.js",
+      "src": "api/index.ts",
       "use": "@vercel/node"
     }
   ],
   "routes": [
     {
       "src": "/(.*)",
-      "dest": "dist/main.js"
+      "dest": "api/index.ts"
     }
   ],
   "buildCommand": "npx nest build",