text: // Copyright Joyent, Inc. and other Node contributors.
  //
  // Permission is hereby granted, free of charge, to any person obtaining a
  // copy of this software and associated documentation files (the
  // "Software"), to deal in the Software without restriction, including
  // without limitation the rights to use, copy, modify, merge, publish,
  // distribute, sublicense, and/or sell copies of the Software, and to permit
  // persons to whom the Software is furnished to do so, subject to the
  // following conditions:
  //
  // The above copyright notice and this permission notice shall be included
  // in all copies or substantial portions of the Software.
  //
  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
  // NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
  // DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  // USE OR OTHER DEALINGS IN THE SOFTWARE.
  
  'use strict';
  // Verify that the 'upgrade' header causes an 'upgrade' event to be emitted to
  // the HTTP client. This test uses a raw TCP server to better control server
  // behavior.
  
  const common = require('../common');
  const assert = require('assert');
  
  const http = require('http');
  const net = require('net');
  
  // Create a TCP server
  const srv = net.createServer(function(c) {
    c.on('data', function(d) {
      c.write('HTTP/1.1 101\r\n');
      c.write('hello: world\r\n');
      c.write('connection: upgrade\r\n');
      c.write('upgrade: websocket\r\n');
      c.write('\r\n');
      c.write('nurtzo');
    });
  
    c.on('end', function() {
      c.end();
    });
  });
  
  srv.listen(0, '127.0.0.1', common.mustCall(function() {
  
    const options = {
      port: this.address().port,
      host: '127.0.0.1',
      headers: {
        'connection': 'upgrade',
        'upgrade': 'websocket'
      }
    };
    const name = `${options.host}:${options.port}`;
  
    const req = http.request(options);
    req.end();
  
    req.on('upgrade', common.mustCall(function(res, socket, upgradeHead) {
      let recvData = upgradeHead;
      socket.on('data', function(d) {
        recvData += d;
      });
  
      socket.on('close', common.mustCall(function() {
        assert.strictEqual(recvData.toString(), 'nurtzo');
      }));
  
      console.log(res.headers);
      const expectedHeaders = { 'hello': 'world',
                                'connection': 'upgrade',
                                'upgrade': 'websocket' };
      assert.deepStrictEqual(expectedHeaders, res.headers);
  
      // Make sure this request got removed from the pool.
      assert(!http.globalAgent.sockets.hasOwnProperty(name));
  
      req.on('close', common.mustCall(function() {
        socket.end();
        srv.close();
      }));
    }));
  }));
  