如何使用koajs下载csv文件

$ mkdir koa-app
$ cd koa-app
$ npm init -y
$ npm install koa koa-router koa-static --save

const Koa = require('koa');
const Router = require('koa-router');
const fs = require('fs');

const app = new Koa();
const router = new Router();

router.get('/download', async (ctx) => {
  const csvData = 'id,name,email\n1,John Doe,john@example.com\n2,Jane Smith,jane@example.com';

  ctx.set('Content-Disposition', 'attachment; filename="data.csv"');
  ctx.set('Content-Type', 'text/csv');
  ctx.body = csvData;
});

app.use(router.routes());

app.listen(3000, () => {
  console.log('Server is running on http://localhost:3000');
});

$ node app.js