Cancel() public method

public Cancel ( ) : void
return void
Example #1
0
        private void PollingLoop(IConnection connection, string data, System.Action initializeCallback, Action <Exception> errorCallback, bool raiseReconnect)
        {
            string _url = connection.Url;
            var    _reconnectTokenSource = new CancellationTokenSource();
            int    _reconnectFired       = 0;

            if (connection.MessageId == null)
            {
                _url += "connect";
            }
            else if (raiseReconnect)
            {
                _url += "reconnect";
            }

            _url += GetReceiveQueryString(connection, data);

            //Debug.WriteLine("LongPollingTransport: PollingLoop for [{0}]", _url);

            var _signal = m_httpClient.PostAsync(
                _url,
                PrepareRequest(connection),
                new Dictionary <string, string> {
                { "groups", GetSerializedGroups(connection) }
            });

            _signal.Finished += (sender, e) =>
            {
                // Clear the pending request
                connection.Items.Remove(c_httpRequestKey);

                bool _shouldRaiseReconnect = false;
                bool _disconnectedReceived = false;

                try
                {
                    if (!e.Result.IsFaulted)
                    {
                        if (raiseReconnect)
                        {
                            // If the timeout for the reconnect hasn't fired as yet just fire the
                            // event here before any incoming messages are processed
                            FireReconnected(connection, _reconnectTokenSource, ref _reconnectFired);
                        }

                        // Get the response
                        var _raw = e.Result.ReadAsString();

                        //Debug.WriteLine("LongPollingTransport: Receive [{0}]", _raw);

                        if (!String.IsNullOrEmpty(_raw))
                        {
                            ProcessResponse(connection, _raw, out _shouldRaiseReconnect, out _disconnectedReceived);
                        }
                    }
                }
                finally
                {
                    if (_disconnectedReceived)
                    {
                        connection.Stop();
                    }
                    else
                    {
                        bool _requestAborted = false;

                        if (e.Result.IsFaulted)
                        {
                            // Cancel the previous reconnect event
                            _reconnectTokenSource.Cancel();

                            // Raise the reconnect event if we successfully reconnect after failing
                            _shouldRaiseReconnect = true;

                            // Get the underlying exception
                            Exception exception = e.Result.Exception.GetBaseException();

                            // If the error callback isn't null then raise it and don't continue polling
                            if (errorCallback != null)
                            {
                                // Raise on error
                                connection.OnError(exception);

                                // Call the callback
                                errorCallback(exception);
                            }
                            else
                            {
                                // Figure out if the request was aborted
                                _requestAborted = IsRequestAborted(exception);

                                // Sometimes a connection might have been closed by the server before we get to write anything
                                // so just try again and don't raise OnError.
                                if (!_requestAborted && !(exception is IOException))
                                {
                                    // Raise on error
                                    connection.OnError(exception);

                                    // If the connection is still active after raising the error event wait for 2 seconds
                                    // before polling again so we aren't hammering the server
                                    Thread.Sleep(m_errorDelay);
                                    if (connection.IsActive)
                                    {
                                        PollingLoop(
                                            connection,
                                            data,
                                            null,                   // initializeCallback
                                            null,                   // errorCallback
                                            _shouldRaiseReconnect); // raiseReconnect
                                    }
                                }
                            }
                        }
                        else
                        {
                            // Continue polling if there was no error
                            if (connection.IsActive)
                            {
                                PollingLoop(
                                    connection,
                                    data,
                                    null,                   // initializeCallback
                                    null,                   // errorCallback
                                    _shouldRaiseReconnect); // raiseReconnect
                            }
                        }
                    }
                }
            };

            if (initializeCallback != null)
            {
                initializeCallback();
            }

            if (raiseReconnect)
            {
                Thread.Sleep(ReconnectDelay);

                // Fire the reconnect event after the delay. This gives the
                FireReconnected(connection, _reconnectTokenSource, ref _reconnectFired);
            }
        }