JSON结果下载zip文件不起作用

const express = require('express');
const fs = require('fs');
const archiver = require('archiver');

const app = express();

app.get('/download', (req, res) => {
  // 生成zip文件
  const output = fs.createWriteStream('filename.zip');
  const archive = archiver('zip', {
    zlib: { level: 9 } // 压缩级别
  });

  output.on('close', () => {
    console.log('Zip file created');
  });

  archive.pipe(output);
  archive.file('file1.txt', { name: 'file1.txt' });
  archive.file('file2.txt', { name: 'file2.txt' });
  archive.finalize();

  // 设置响应头
  res.setHeader('Content-Type', 'application/zip');
  res.setHeader('Content-Disposition', 'attachment; filename=filename.zip');

  // 将zip文件发送给客户端
  archive.pipe(res);
});

app.listen(3000, () => {
  console.log('Server started on port 3000');
});