code: function getPort(req) {
  		if (req.connection && req.connection.localPort) {
  			return req.connection.localPort.toString();
  		}
  		const host = req.headers && req.headers.host;
  		let protocolSrc = 80;
  		if (host && ((host.match(/:/g) || []).length) === 1) {
  			const possiblePort = host.split(':')[1];
  			protocolSrc = isNaN(possiblePort) ? protocolSrc : possiblePort;
  		}
  		return protocolSrc;
  	}
docs: derive the port if its in the host string.
  @param  {Object} req a express req object
  @return {string}     string representation of port