Esempio n. 1
0
        public async Task ConnectionIdsCantBeUsedAsGroups()
        {
            using (var host = new MemoryHost())
            {
                IProtectedData protectedData = null;

                host.Configure(app =>
                {
                    var config = new ConnectionConfiguration
                    {
                        Resolver = new DefaultDependencyResolver()
                    };

                    app.MapSignalR <MyConnection>("/echo", config);

                    protectedData = config.Resolver.Resolve <IProtectedData>();
                });

                var connection = new Client.Connection("http://memoryhost/echo");

                using (connection)
                {
                    var connectionTcs = new TaskCompletionSource <string>();
                    var spyTcs        = new TaskCompletionSource <string>();

                    connection.Received += data =>
                    {
                        connectionTcs.SetResult(data.Trim());
                    };

                    await connection.Start(host).OrTimeout();

                    EventSourceStreamReader reader = null;

                    await Task.Run(async() =>
                    {
                        var url      = GetUrl(protectedData, connection);
                        var response = await host.Get(url, r => { }, isLongRunning: true);
                        reader       = new EventSourceStreamReader(connection, response.GetStream());

                        reader.Message = sseEvent =>
                        {
                            if (sseEvent.EventType == EventType.Data &&
                                sseEvent.Data != "initialized" &&
                                sseEvent.Data != "{}")
                            {
                                spyTcs.TrySetResult(sseEvent.Data);
                            }
                        };

                        reader.Start();
                    });

                    await connection.Send("STUFFF").OrTimeout();

                    Assert.Equal("STUFFF", await connectionTcs.Task.OrTimeout());
                }
            }
        }
Esempio n. 2
0
        public void CloseThrowsSouldntTakeProcessDown()
        {
            var memoryStream = MemoryStream("");
            var eventSource  = new EventSourceStreamReader(memoryStream);

            eventSource.Closed = (ex) =>
            {
                throw new Exception("Throw on closed");
            };

            eventSource.Start();

            Thread.Sleep(TimeSpan.FromSeconds(5));
        }
        public void ReadTriggersOpenedOnOpen()
        {
            var memoryStream = MemoryStream("data:somedata\n\n");
            var wh           = new ManualResetEvent(false);
            var tcs          = new TaskCompletionSource <string>();
            var eventSource  = new EventSourceStreamReader(memoryStream);

            eventSource.Opened  = () => wh.Set();
            eventSource.Message = sseEvent => tcs.TrySetResult(sseEvent.Data);

            eventSource.Start();
            Assert.True(wh.WaitOne(TimeSpan.FromSeconds(5)));
            Assert.True(tcs.Task.Wait(TimeSpan.FromSeconds(5)));
            Assert.Equal("somedata", tcs.Task.Result);
        }
        public void CloseThrowsSouldntTakeProcessDown()
        {
            var memoryStream = MemoryStream("");
            var eventSource  = new EventSourceStreamReader(memoryStream);
            var wh           = new ManualResetEventSlim();

            eventSource.Closed = (ex) =>
            {
                wh.Set();
                throw new Exception("Throw on closed");
            };

            eventSource.Start();

            Assert.True(wh.Wait(TimeSpan.FromSeconds(5)));
        }
Esempio n. 5
0
        public void CloseThrowsSouldntTakeProcessDown()
        {
            var memoryStream = MemoryStream("");
            var eventSource  = new EventSourceStreamReader(memoryStream);

            eventSource.Closed = (ex) =>
            {
                throw new Exception("Throw on closed");
            };

            eventSource.Start();

            // Force any finalizers to run so we can see unhandled task errors
            GC.Collect();
            GC.WaitForPendingFinalizers();

            Thread.Sleep(TimeSpan.FromSeconds(5));
        }
Esempio n. 6
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        private void OpenConnection(IConnection connection,
                                    string data,
                                    CancellationToken disconnectToken,
                                    Action initializeCallback,
                                    Action <Exception> errorCallback)
        {
            // If we're reconnecting add /connect to the url
            bool   reconnecting     = initializeCallback == null;
            var    callbackInvoker  = new ThreadSafeInvoker();
            var    requestDisposer  = new Disposer();
            Action initializeInvoke = () =>
            {
                callbackInvoker.Invoke(initializeCallback);
            };
            var url = connection.Url + (reconnecting ? "reconnect" : "connect") + GetReceiveQueryString(connection, data);

            connection.Trace(TraceLevels.Events, "SSE: GET {0}", url);

            HttpClient.Get(url, req =>
            {
                _request        = req;
                _request.Accept = "text/event-stream";

                connection.PrepareRequest(_request);
            }, isLongRunning: true).ContinueWith(task =>
            {
                if (task.IsFaulted || task.IsCanceled)
                {
                    Exception exception;

                    if (task.IsCanceled)
                    {
                        exception = new OperationCanceledException(Resources.Error_TaskCancelledException);
                    }
                    else
                    {
                        exception = task.Exception.Unwrap();
                    }

                    if (errorCallback != null)
                    {
                        callbackInvoker.Invoke((cb, ex) => cb(ex), errorCallback, exception);
                    }
                    else if (!_stop && reconnecting)
                    {
                        // Only raise the error event if we failed to reconnect
                        connection.OnError(exception);

                        Reconnect(connection, data, disconnectToken);
                    }
                    requestDisposer.Dispose();
                }
                else
                {
                    // If the disconnect token is canceled the response to the task doesn't matter.
                    if (disconnectToken.IsCancellationRequested)
                    {
                        return;
                    }

                    var response  = task.Result;
                    Stream stream = response.GetStream();

                    var eventSource = new EventSourceStreamReader(connection, stream);

                    var esCancellationRegistration = disconnectToken.SafeRegister(state =>
                    {
                        _stop = true;

                        ((IRequest)state).Abort();
                    },
                                                                                  _request);

                    eventSource.Opened = () =>
                    {
                        // This will noop if we're not in the reconnecting state
                        if (connection.ChangeState(ConnectionState.Reconnecting, ConnectionState.Connected))
                        {
                            // Raise the reconnect event if the connection comes back up
                            connection.OnReconnected();
                        }
                    };

                    eventSource.Message = sseEvent =>
                    {
                        if (sseEvent.EventType == EventType.Data)
                        {
                            if (sseEvent.Data.Equals("initialized", StringComparison.OrdinalIgnoreCase))
                            {
                                return;
                            }

                            bool shouldReconnect;
                            bool disconnected;
                            TransportHelper.ProcessResponse(connection, sseEvent.Data, out shouldReconnect, out disconnected, initializeInvoke);

                            if (disconnected)
                            {
                                _stop = true;
                                connection.Disconnect();
                            }
                        }
                    };

                    eventSource.Closed = exception =>
                    {
                        if (exception != null)
                        {
                            // Check if the request is aborted
                            bool isRequestAborted = ExceptionHelper.IsRequestAborted(exception);

                            if (!isRequestAborted)
                            {
                                // Don't raise exceptions if the request was aborted (connection was stopped).
                                connection.OnError(exception);
                            }
                        }

                        requestDisposer.Dispose();
                        esCancellationRegistration.Dispose();
                        response.Dispose();

                        if (_stop)
                        {
                            AbortHandler.CompleteAbort();
                        }
                        else if (AbortHandler.TryCompleteAbort())
                        {
                            // Abort() was called, so don't reconnect
                        }
                        else
                        {
                            Reconnect(connection, data, disconnectToken);
                        }
                    };

                    eventSource.Start();
                }
            });

            var requestCancellationRegistration = disconnectToken.SafeRegister(state =>
            {
                if (state != null)
                {
                    // This will no-op if the request is already finished.
                    ((IRequest)state).Abort();
                }

                if (errorCallback != null)
                {
                    callbackInvoker.Invoke((cb, token) =>
                    {
#if !NET35
                        cb(new OperationCanceledException(Resources.Error_ConnectionCancelled, token));
#else
                        cb(new OperationCanceledException(Resources.Error_ConnectionCancelled));
#endif
                    }, errorCallback, disconnectToken);
                }
            }, _request);

            requestDisposer.Set(requestCancellationRegistration);
        }
Esempio n. 7
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        private void OpenConnection(IConnection connection, string data, Action initializeCallback, Action <Exception> errorCallback)
        {
            // If we're reconnecting add /connect to the url
            bool reconnecting    = initializeCallback == null;
            var  callbackInvoker = new ThreadSafeInvoker();

            var url = (reconnecting ? connection.Url : connection.Url + "connect") + GetReceiveQueryString(connection, data);

            Action <IRequest> prepareRequest = PrepareRequest(connection);

#if NET35
            Debug.WriteLine(String.Format(System.Globalization.CultureInfo.InvariantCulture, "SSE: GET {0}", (object)url));
#else
            Debug.WriteLine("SSE: GET {0}", (object)url);
#endif

            _httpClient.GetAsync(url, request =>
            {
                prepareRequest(request);

                request.Accept = "text/event-stream";
            }).ContinueWith(task =>
            {
                if (task.IsFaulted)
                {
                    Exception exception = task.Exception.Unwrap();
                    if (!ExceptionHelper.IsRequestAborted(exception))
                    {
                        if (errorCallback != null)
                        {
                            callbackInvoker.Invoke((cb, ex) => cb(ex), errorCallback, exception);
                        }
                        else if (reconnecting)
                        {
                            // Only raise the error event if we failed to reconnect
                            connection.OnError(exception);

                            Reconnect(connection, data);
                        }
                    }
                }
                else
                {
                    IResponse response = task.Result;
                    Stream stream      = response.GetResponseStream();

                    var eventSource = new EventSourceStreamReader(stream);
                    bool retry      = true;

                    connection.Items[EventSourceKey] = eventSource;

                    eventSource.Opened = () =>
                    {
                        if (initializeCallback != null)
                        {
                            callbackInvoker.Invoke(initializeCallback);
                        }

                        if (reconnecting && connection.ChangeState(ConnectionState.Reconnecting, ConnectionState.Connected))
                        {
                            // Raise the reconnect event if the connection comes back up
                            connection.OnReconnected();
                        }
                    };

                    eventSource.Message = sseEvent =>
                    {
                        if (sseEvent.Type == EventType.Data)
                        {
                            if (sseEvent.Data.Equals("initialized", StringComparison.OrdinalIgnoreCase))
                            {
                                return;
                            }

                            bool timedOut;
                            bool disconnected;
                            ProcessResponse(connection, sseEvent.Data, out timedOut, out disconnected);

                            if (disconnected)
                            {
                                retry = false;
                            }
                        }
                    };

                    eventSource.Closed = exception =>
                    {
                        if (exception != null && !ExceptionHelper.IsRequestAborted(exception))
                        {
                            // Don't raise exceptions if the request was aborted (connection was stopped).
                            connection.OnError(exception);
                        }

                        // See http://msdn.microsoft.com/en-us/library/system.net.httpwebresponse.close.aspx
                        response.Close();

                        if (retry)
                        {
                            Reconnect(connection, data);
                        }
                        else
                        {
                            connection.Stop();
                        }
                    };

                    eventSource.Start();
                }
            });

            if (errorCallback != null)
            {
                TaskAsyncHelper.Delay(ConnectionTimeout).Then(() =>
                {
                    callbackInvoker.Invoke((conn, cb) =>
                    {
                        // Stop the connection
                        Stop(conn);

                        // Connection timeout occured
                        cb(new TimeoutException());
                    },
                                           connection,
                                           errorCallback);
                });
            }
        }
Esempio n. 8
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        public async Task GroupsTokenIsPerConnectionId()
        {
            using (var host = new MemoryHost())
            {
                IProtectedData protectedData = null;

                host.Configure(app =>
                {
                    var config = new HubConfiguration
                    {
                        Resolver = new DefaultDependencyResolver()
                    };

                    app.MapSignalR <MyGroupConnection>("/echo", config);

                    protectedData = config.Resolver.Resolve <IProtectedData>();
                });

                var connection = new Client.Connection("http://memoryhost/echo");

                using (connection)
                {
                    var inGroup = new AsyncManualResetEvent();

                    connection.Received += data =>
                    {
                        if (data == "group")
                        {
                            inGroup.Set();
                        }
                    };

                    await connection.Start(host);

                    await inGroup.WaitAsync(TimeSpan.FromSeconds(10));

                    Assert.NotNull(connection.GroupsToken);

                    var spyWh            = new AsyncManualResetEvent();
                    var hackerConnection = new Client.Connection(connection.Url)
                    {
                        ConnectionId = "hacker"
                    };

                    var url      = GetUrl(protectedData, connection, connection.GroupsToken);
                    var response = await host.Get(url, r => { }, isLongRunning : true);

                    var reader = new EventSourceStreamReader(hackerConnection, response.GetStream());

                    reader.Message = sseEvent =>
                    {
                        if (sseEvent.EventType == EventType.Data &&
                            sseEvent.Data != "initialized" &&
                            sseEvent.Data != "{}")
                        {
                            spyWh.Set();
                        }
                    };

                    reader.Start();
                    await connection.Send("random");

                    Assert.False(await spyWh.WaitAsync(TimeSpan.FromSeconds(5)));
                }
            }
        }
Esempio n. 9
0
        public void ConnectionIdsCantBeUsedAsGroups()
        {
            using (var host = new MemoryHost())
            {
                IProtectedData protectedData = null;

                host.Configure(app =>
                {
                    var config = new ConnectionConfiguration
                    {
                        Resolver = new DefaultDependencyResolver()
                    };

                    app.MapConnection <MyConnection>("/echo", config);

                    protectedData = config.Resolver.Resolve <IProtectedData>();
                });

                var connection = new Client.Connection("http://memoryhost/echo");

                var connectionTcs = new TaskCompletionSource <string>();
                var spyTcs        = new TaskCompletionSource <string>();

                connection.Received += data =>
                {
                    connectionTcs.SetResult(data.Trim());
                };

                connection.Start(host).Wait();

                var tcs = new TaskCompletionSource <object>();
                EventSourceStreamReader reader = null;

                Task.Run(async() =>
                {
                    try
                    {
                        string url   = GetUrl(protectedData, connection);
                        var response = await host.Get(url);
                        reader       = new EventSourceStreamReader(connection, response.GetStream());

                        reader.Message = sseEvent =>
                        {
                            if (sseEvent.EventType == EventType.Data &&
                                sseEvent.Data != "initialized" &&
                                sseEvent.Data != "{}")
                            {
                                spyTcs.TrySetResult(sseEvent.Data);
                            }
                        };

                        reader.Start();
                        tcs.TrySetResult(null);
                    }
                    catch (Exception ex)
                    {
                        tcs.TrySetException(ex);
                    }
                });

                tcs.Task.Wait();

                connection.SendWithTimeout("STUFFF");

                Assert.True(connectionTcs.Task.Wait(TimeSpan.FromSeconds(5)));
                Assert.Equal("STUFFF", connectionTcs.Task.Result);
                Assert.False(spyTcs.Task.Wait(TimeSpan.FromSeconds(5)));

                connection.Stop();
            }
        }
Esempio n. 10
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        private void OpenConnection(IConnection connection,
                                    string data,
                                    CancellationToken disconnectToken,
                                    Action initializeCallback,
                                    Action <Exception> errorCallback)
        {
            // If we're reconnecting add /connect to the url
            bool reconnecting    = initializeCallback == null;
            var  callbackInvoker = new ThreadSafeInvoker();
            var  requestDisposer = new Disposer();

            var url = (reconnecting ? connection.Url : connection.Url + "connect") + GetReceiveQueryString(connection, data);

            connection.Trace(TraceLevels.Events, "SSE: GET {0}", url);

            HttpClient.Get(url, req =>
            {
                _request = req;
                connection.PrepareRequest(_request);

                _request.Accept = "text/event-stream";
            }).ContinueWith(task =>
            {
                if (task.IsFaulted)
                {
                    Exception exception = task.Exception.Unwrap();
                    if (!ExceptionHelper.IsRequestAborted(exception))
                    {
                        if (errorCallback != null)
                        {
                            callbackInvoker.Invoke((cb, ex) => cb(ex), errorCallback, exception);
                        }
                        else if (reconnecting)
                        {
                            // Only raise the error event if we failed to reconnect
                            connection.OnError(exception);

                            Reconnect(connection, data, disconnectToken);
                        }
                    }
                    requestDisposer.Dispose();
                }
                else
                {
                    var response  = task.Result;
                    Stream stream = response.GetStream();

                    var eventSource = new EventSourceStreamReader(connection, stream);

                    bool retry = true;

                    var esCancellationRegistration = disconnectToken.SafeRegister(state =>
                    {
                        retry = false;

                        ((IRequest)state).Abort();
                    },
                                                                                  _request);

                    eventSource.Opened = () =>
                    {
                        // If we're not reconnecting, then we're starting the transport for the first time. Trigger callback only on first start.
                        if (!reconnecting)
                        {
                            callbackInvoker.Invoke(initializeCallback);
                        }
                        else if (connection.ChangeState(ConnectionState.Reconnecting, ConnectionState.Connected))
                        {
                            // Raise the reconnect event if the connection comes back up
                            connection.OnReconnected();
                        }
                    };

                    eventSource.Message = sseEvent =>
                    {
                        if (sseEvent.EventType == EventType.Data)
                        {
                            if (sseEvent.Data.Equals("initialized", StringComparison.OrdinalIgnoreCase))
                            {
                                return;
                            }

                            bool timedOut;
                            bool disconnected;
                            TransportHelper.ProcessResponse(connection, sseEvent.Data, out timedOut, out disconnected);

                            if (disconnected)
                            {
                                retry = false;
                                connection.Disconnect();
                            }
                        }
                    };

                    eventSource.Closed = exception =>
                    {
                        if (exception != null)
                        {
                            // Check if the request is aborted
                            bool isRequestAborted = ExceptionHelper.IsRequestAborted(exception);

                            if (!isRequestAborted)
                            {
                                // Don't raise exceptions if the request was aborted (connection was stopped).
                                connection.OnError(exception);
                            }
                        }
                        requestDisposer.Dispose();
                        esCancellationRegistration.Dispose();
                        response.Dispose();

                        if (AbortResetEvent != null)
                        {
                            AbortResetEvent.Set();
                        }
                        else if (retry)
                        {
                            Reconnect(connection, data, disconnectToken);
                        }
                    };

                    eventSource.Start();
                }
            });

            var requestCancellationRegistration = disconnectToken.SafeRegister(state =>
            {
                if (state != null)
                {
                    // This will no-op if the request is already finished.
                    ((IRequest)state).Abort();
                }

                if (errorCallback != null)
                {
                    callbackInvoker.Invoke((cb, token) =>
                    {
#if NET35 || WINDOWS_PHONE
                        cb(new OperationCanceledException(Resources.Error_ConnectionCancelled));
#else
                        cb(new OperationCanceledException(Resources.Error_ConnectionCancelled, token));
#endif
                    }, errorCallback, disconnectToken);
                }
            }, _request);

            requestDisposer.Set(requestCancellationRegistration);

            if (errorCallback != null)
            {
                TaskAsyncHelper.Delay(ConnectionTimeout).Then(() =>
                {
                    callbackInvoker.Invoke((conn, cb) =>
                    {
                        // Abort the request before cancelling
                        _request.Abort();

                        // Connection timeout occurred
                        cb(new TimeoutException());
                    },
                                           connection,
                                           errorCallback);
                });
            }
        }
Esempio n. 11
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        internal void OpenConnection(IConnection connection, string data, CancellationToken disconnectToken, bool reconnecting)
        {
            // If we're reconnecting add /connect to the url
            var url = reconnecting
                ? UrlBuilder.BuildReconnect(connection, Name, data)
                : UrlBuilder.BuildConnect(connection, Name, data);

            connection.Trace(TraceLevels.Events, "SSE: GET {0}", url);

            var getTask = HttpClient.Get(url, req =>
            {
                _request        = req;
                _request.Accept = "text/event-stream";

                connection.PrepareRequest(_request);
            }, isLongRunning: true);

            var requestCancellationRegistration = disconnectToken.SafeRegister(state =>
            {
                _stop = true;

                // This will no-op if the request is already finished.
                ((IRequest)state).Abort();
            }, _request);

            getTask.ContinueWith(task =>
            {
                if (task.IsFaulted || task.IsCanceled)
                {
                    var exception = task.IsCanceled
                        ? new OperationCanceledException(Resources.Error_TaskCancelledException)
                        : task.Exception.Unwrap();

                    if (!reconnecting)
                    {
                        // It shouldn't be possible for Start to have already succeeded at this point.
                        TryFailStart(exception);
                    }
                    else if (!_stop)
                    {
                        // Only raise the error event if the error wasn't raised from Start and we're reconnecting.
                        connection.OnError(exception);

                        Reconnect(connection, data, disconnectToken);
                    }

                    requestCancellationRegistration.Dispose();
                }
                else
                {
                    // If the disconnect token is canceled the response to the task doesn't matter.
                    if (disconnectToken.IsCancellationRequested)
                    {
                        return;
                    }

                    var response  = task.Result;
                    Stream stream = response.GetStream();

                    var eventSource = new EventSourceStreamReader(connection, stream);

                    eventSource.Opened = () =>
                    {
                        // This will noop if we're not in the reconnecting state
                        if (connection.ChangeState(ConnectionState.Reconnecting, ConnectionState.Connected))
                        {
                            // Raise the reconnect event if the connection comes back up
                            connection.OnReconnected();
                        }
                    };

                    eventSource.Message = sseEvent =>
                    {
                        if (sseEvent.EventType == EventType.Data &&
                            !sseEvent.Data.Equals("initialized", StringComparison.OrdinalIgnoreCase))
                        {
                            ProcessResponse(connection, sseEvent.Data);
                        }
                    };

                    eventSource.Closed = exception =>
                    {
                        // Make sure to try to fail start even if the disconnectToken tripped and set _stop to true.
                        var startFailed = TryFailStart(exception);

                        if (exception != null && !startFailed)
                        {
                            // Check if the request is aborted
                            if (!ExceptionHelper.IsRequestAborted(exception))
                            {
                                // Don't raise exceptions if the request was aborted (connection was stopped).
                                connection.OnError(exception);
                            }
                        }

                        requestCancellationRegistration.Dispose();
                        response.Dispose();

                        if (_stop)
                        {
                            AbortHandler.CompleteAbort();
                        }
                        else if (!AbortHandler.TryCompleteAbort() && !startFailed)
                        {
                            // If Abort() was called or Start() failed, don't reconnect.
                            Reconnect(connection, data, disconnectToken);
                        }
                    };

                    eventSource.Start();
                }
            });
        }
Esempio n. 12
0
        private void OpenConnection(IConnection connection, string data, Action initializeCallback, Action <Exception> errorCallback)
        {
            // If we're reconnecting add /connect to the url
            bool reconnecting = initializeCallback == null;

            var url = (reconnecting ? connection.Url : connection.Url + "connect") + GetReceiveQueryString(connection, data);

            Action <IRequest> prepareRequest = PrepareRequest(connection);

            Debug.WriteLine("SSE: GET {0}", (object)url);

            _httpClient.GetAsync(url, request =>
            {
                prepareRequest(request);

                request.Accept = "text/event-stream";
            }).ContinueWith(task =>
            {
                if (task.IsFaulted)
                {
                    var exception = task.Exception.Unwrap();
                    if (!ExceptionHelper.IsRequestAborted(exception))
                    {
                        if (errorCallback != null &&
                            Interlocked.Exchange(ref _initializedCalled, 1) == 0)
                        {
                            errorCallback(exception);
                        }
                        else if (reconnecting)
                        {
                            // Only raise the error event if we failed to reconnect
                            connection.OnError(exception);
                        }
                    }

                    if (reconnecting && !CancellationToken.IsCancellationRequested)
                    {
                        connection.State = ConnectionState.Reconnecting;

                        // Retry
                        Reconnect(connection, data);
                        return;
                    }
                }
                else
                {
                    IResponse response = task.Result;
                    Stream stream      = response.GetResponseStream();

                    var eventSource = new EventSourceStreamReader(stream);
                    bool retry      = true;

                    // When this fires close the event source
                    CancellationToken.Register(() => eventSource.Close());

                    eventSource.Opened = () =>
                    {
                        if (Interlocked.CompareExchange(ref _initializedCalled, 1, 0) == 0)
                        {
                            initializeCallback();
                        }

                        if (reconnecting)
                        {
                            // Change the status to connected
                            connection.State = ConnectionState.Connected;

                            // Raise the reconnect event if the connection comes back up
                            connection.OnReconnected();
                        }
                    };

                    eventSource.Error = connection.OnError;

                    eventSource.Message = sseEvent =>
                    {
                        if (sseEvent.Type == EventType.Data)
                        {
                            if (sseEvent.Data.Equals("initialized", StringComparison.OrdinalIgnoreCase))
                            {
                                return;
                            }

                            bool timedOut;
                            bool disconnected;
                            ProcessResponse(connection, sseEvent.Data, out timedOut, out disconnected);

                            if (disconnected)
                            {
                                retry = false;
                            }
                        }
                    };

                    eventSource.Closed = () =>
                    {
                        response.Close();

                        if (retry && !CancellationToken.IsCancellationRequested)
                        {
                            // If we're retrying then just go again
                            connection.State = ConnectionState.Reconnecting;

                            Reconnect(connection, data);
                        }
                        else
                        {
                            connection.Stop();
                        }
                    };

                    if (!CancellationToken.IsCancellationRequested)
                    {
                        eventSource.Start();
                    }
                }
            });

            if (initializeCallback != null)
            {
                TaskAsyncHelper.Delay(ConnectionTimeout).Then(() =>
                {
                    if (Interlocked.CompareExchange(ref _initializedCalled, 1, 0) == 0)
                    {
                        // Stop the connection
                        Stop(connection);

                        // Connection timeout occured
                        errorCallback(new TimeoutException());
                    }
                });
            }
        }
        private void OpenConnection(IConnection connection,
                                    string data,
                                    CancellationToken disconnectToken,
                                    Action initializeCallback,
                                    Action <Exception> errorCallback)
        {
            // If we're reconnecting add /connect to the url
            bool reconnecting    = initializeCallback == null;
            var  callbackInvoker = new ThreadSafeInvoker();
            var  requestDisposer = new Disposer();

            var      url     = (reconnecting ? connection.Url : connection.Url + "connect") + GetReceiveQueryString(connection, data);
            IRequest request = null;

#if NET35
            Debug.WriteLine(String.Format(CultureInfo.InvariantCulture, "SSE: GET {0}", (object)url));
#else
            Debug.WriteLine("SSE: GET {0}", (object)url);
#endif

            HttpClient.GetAsync(url, req =>
            {
                request = req;
                connection.PrepareRequest(request);

                request.Accept = "text/event-stream";
            }).ContinueWith(task =>
            {
                if (task.IsFaulted)
                {
                    Exception exception = task.Exception.Unwrap();
                    if (!ExceptionHelper.IsRequestAborted(exception))
                    {
                        if (errorCallback != null)
                        {
                            callbackInvoker.Invoke((cb, ex) => cb(ex), errorCallback, exception);
                        }
                        else if (reconnecting)
                        {
                            // Only raise the error event if we failed to reconnect
                            connection.OnError(exception);

                            Reconnect(connection, data, disconnectToken);
                        }
                    }
                    requestDisposer.Dispose();
                }
                else
                {
                    IResponse response = task.Result;
                    Stream stream      = response.GetResponseStream();

                    var eventSource = new EventSourceStreamReader(stream);
                    bool retry      = true;

                    var esCancellationRegistration = disconnectToken.SafeRegister(es =>
                    {
                        retry = false;
                        es.Close();
                    }, eventSource);

                    eventSource.Opened = () =>
                    {
                        if (!reconnecting)
                        {
                            callbackInvoker.Invoke(initializeCallback);
                        }
                        else if (connection.ChangeState(ConnectionState.Reconnecting, ConnectionState.Connected))
                        {
                            // Raise the reconnect event if the connection comes back up
                            connection.OnReconnected();
                        }
                    };

                    eventSource.Message = sseEvent =>
                    {
                        if (sseEvent.EventType == EventType.Data)
                        {
                            if (sseEvent.Data.Equals("initialized", StringComparison.OrdinalIgnoreCase))
                            {
                                return;
                            }

                            bool timedOut;
                            bool disconnected;
                            ProcessResponse(connection, sseEvent.Data, out timedOut, out disconnected);

                            if (disconnected)
                            {
                                retry = false;
                                connection.Disconnect();
                            }
                        }
                    };

                    eventSource.Closed = exception =>
                    {
                        bool isRequestAborted = false;

                        if (exception != null)
                        {
                            // Check if the request is aborted
                            isRequestAborted = ExceptionHelper.IsRequestAborted(exception);

                            if (!isRequestAborted)
                            {
                                // Don't raise exceptions if the request was aborted (connection was stopped).
                                connection.OnError(exception);
                            }
                        }

                        // Skip reconnect attempt for aborted requests
                        if (!isRequestAborted && retry)
                        {
                            Reconnect(connection, data, disconnectToken);
                        }
                    };

                    // See http://msdn.microsoft.com/en-us/library/system.net.httpwebresponse.close.aspx
                    eventSource.Disabled = () =>
                    {
                        requestDisposer.Dispose();
                        esCancellationRegistration.Dispose();
                        response.Close();
                    };

                    eventSource.Start();
                }
            });

            var requestCancellationRegistration = disconnectToken.SafeRegister(req =>
            {
                if (req != null)
                {
                    // This will no-op if the request is already finished.
                    req.Abort();
                }

                if (errorCallback != null)
                {
                    callbackInvoker.Invoke((cb, token) =>
                    {
#if NET35 || WINDOWS_PHONE
                        cb(new OperationCanceledException(Resources.Error_ConnectionCancelled));
#else
                        cb(new OperationCanceledException(Resources.Error_ConnectionCancelled, token));
#endif
                    }, errorCallback, disconnectToken);
                }
            }, request);

            requestDisposer.Set(requestCancellationRegistration);

            if (errorCallback != null)
            {
                TaskAsyncHelper.Delay(ConnectionTimeout).Then(() =>
                {
                    callbackInvoker.Invoke((conn, cb) =>
                    {
                        connection.Disconnect();

                        // Connection timeout occurred
                        cb(new TimeoutException());
                    },
                                           connection,
                                           errorCallback);
                });
            }
        }