server to proxy requests to CSSWG bikeshed

bikeshedproxy.js

#!/usr/bin/env node
const crypto = require('crypto');
const http = require('http');
const https = require('https');
const fs = require('fs');

http.createServer((req, res) => {
  if (req.url !== '/') {
    res.writeHead(404);
    res.end();
    return;
  }
  const boundary = `--boundary-${crypto.randomBytes(8).toString('hex')}`;
  const prefix = `--${boundary}\r\nContent-Disposition: form-data; name="die-on"\r\n\r\nwarning\r\n--${boundary}\r\nContent-Disposition: form-data; name="file"; filename="index.bs"\r\nContent-Type: text/plain\r\n\r\n`;
  const suffix = `\r\n--${boundary}--\r\n`;

  console.log('got request');
  const fd = fs.open('index.bs', 'r', (err, fd) => {
    if (err) { res.end(); return; }
    console.log('opened file');
    fs.fstat(fd, (err, stats) => {
      if (err) { res.end(); fs.close(fd, () => {}); return; }
      console.log('stat file');
      let bsReq = https.request('https://api.csswg.org/bikeshed/',
          {headers: {'Accept': 'text/plain, text/html', 'Content-Type': `multipart/form-data; boundary=${boundary}`, 'Content-Length': stats.size + prefix.length + suffix.length},
           method: 'POST'},
          (bsRes) => {
        console.log('response started', bsRes.statusCode, bsRes.statusMessage, bsRes.headers);
        res.writeHead(bsRes.statusCode, bsRes.statusMessage, bsRes.headers);
        bsRes.pipe(res);
      });
      bsReq.write(prefix);

      console.log('creating read stream');
      const sourceStream = fs.createReadStream(null, {fd});
      sourceStream.pipe(bsReq, {end: false});
      sourceStream.on('end', () => { bsReq.end(suffix); fs.close(fd, () => {}); console.log('end'); });
    });
  });
}).listen(8000);