Workers 设计模式

# Workers 开发模式 ## 错误处理 typescript class HTTPError extends Error { constructor(public status: number, message: string) { super(message); } } export default { async fetch(request: Request, env: Env): Promise { try { return await handleRequest(request, env); } catch (error) { if (error instanceof HTTPError) { return new Response(JSON.stringify({ error: error.message }), { status: error.status, headers: { 'Content-Type': 'application/json' } }); } return new Response('Internal Server Error', { status: 500 }); } }, }; ## CORS typescript const corsHeaders = { 'Access-Control-Allow-Origin': '*', 'Access-Control-Allow-Methods': 'GET, POST, PUT, DELETE, OPTIONS' }; if (request.method === 'OPTIONS') return new Response(null, { headers: corsHeaders }); ## 路由 typescript const router = { 'GET /api/users': handleGetUsers, 'POST /api/users': handleCreateUser }; const handler = router[`${request.method} ${url.pathname}`]; return handler ? handler(request, env) : new Response('Not Found', { status: 404 }); **生产环境**: 使用 Hono, itty-router 或 Worktop (参考 [frameworks.md](./frameworks.md)) ## 请求验证 (Zod) typescript import { z } from 'zod'; const userSchema = z.object({ name: z.string().min(1).max(100), email: z.string().email(), age: z.number().int().positive().optional(), }); async function handleCreateUser(request: Request) { try { const body = await request.json(); const validated = userSchema.parse(body); // 数据无效时抛出异常 return new Response(JSON.stringify({ id: 1, ...validated }), { status: 201, headers: { 'Content-Type': 'application/json' }, }); } catch (err) { if (err instanceof z.ZodError) { return new Response(JSON.stringify({ errors: err.errors }), { status: 400 }); } throw err; } } **配合 Hono**: 使用 `@hono/zod-validator` 进行自动验证 (参考 [frameworks.md](./frameworks.md)) ## 性能 typescript // ❌ 串行 const user = await fetch('/api/user/1'); const posts = await fetch('/api/posts?user=1'); // ✅ 并行 const [user, posts] = await Promise.all([fetch('/api/user/1'), fetch('/api/posts?user=1')]); ## 流式传输 typescript const stream = new ReadableStream({ async start(controller) { for (let i = 0; i < 1000; i++) { controller.enqueue(new TextEncoder().encode(`Item ${i}n`)); if (i % 100 ==