code: function initializeConnection(opts) {
      opts.request.socket.setTimeout(0);
      opts.request.socket.setNoDelay(true);
      opts.request.socket.setKeepAlive(true);
      opts.response.writeHead(200, {
          'Content-Type': 'text/event-stream;charset=UTF-8',
          'Cache-Control': 'no-cache',
          'Connection': 'keep-alive'
      });
  
      opts.response.write(':ok\n\n');
  
      // Only set retry if it has a sane value
      var retry = opts.retry | 0;
      if (retry) {
          opts.response.write('retry: ' + retry + '\n');
      }
  
      // Should we delivar a "preamble" to the client? Required in some cases by Internet Explorer,
      // see https://github.com/amvtek/EventSource/wiki/UserGuide for more information
      if (opts.preamble) {
          opts.response.write(':' + preambleData);
      }
  
      flush(opts.response);
  }
docs: Sends the initial, required headers for the connection
  
  @param {Object}   opts           Options object
  @param {Request}  opts.request   Request object to use
  @param {Response} opts.response  Response object to use
  @param {Number}   opts.retry     Time in milliseconds to specify as reconnection timeout
  @param {Boolean}  opts.preamble  Whether to send a "preamble" of dummy data to the client