Transport mechanism used on server, that directly uses RequestHandler, used by createLoopBackConnection.

class LoopBackTransport extends Transport {
 /**
  * RequestFactory is a function like LoopBackRequest.request() that returns
  * [Future<LoopBackRequest>].
  */
 final _sendLoopBackRequest;

 /**
  * Id of the user currently authenticated.
  */
 final _authenticatedUserId;

 /**
  * Indicates whether a [LoopBackRequest] is currently on the way.
  */
 bool _isRunning = false;

 bool _isDirty;

 LoopBackTransport(this._sendLoopBackRequest, [this._authenticatedUserId = null]);

 markDirty() {
   _isDirty = true;
   performRequest();
 }

 bool _shouldSendLoopBackRequest() {
   return !_isRunning &&
       _isDirty;
 }

 void _openRequest() {
   _isRunning = true;
   _isDirty = false;
 }

 void _closeRequest() {
   _isRunning = false;
   performRequest();
 }

 /**
  * Begins performing LoopBackRequest. Is not launched if another request is
  * already running or the request Queue is empty. Sets [_isRunning] as true
  * for the time this request is running and hooks up another request
  * after this one.
  */
 void performRequest() {
   if (!_shouldSendLoopBackRequest()) {
     return;
   }

   _openRequest();

   _sendLoopBackRequest(JSON.encode(_prepareRequest()), _authenticatedUserId)
   .then((response) {
     _handleResponse({'responses': response, 'authenticatedUserId': _authenticatedUserId});
     _closeRequest();
   }).catchError((e) => _handleError(new FailedRequestException()));

 }
}