使用express发送二进制pdf文件

$ mkdir myapp
$ cd myapp
$ npm init -y
$ npm install express --save

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

const app = express();

app.get('/pdf', (req, res) => {
  const filePath = './pdfs/sample.pdf';
  const stat = fs.statSync(filePath);

  res.setHeader('Content-Length', stat.size);
  res.setHeader('Content-Type', 'application/pdf');
  res.setHeader('Content-Disposition', 'attachment; filename=sample.pdf');

  const stream = fs.createReadStream(filePath);
  stream.pipe(res);
});

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

$ node app.js