示例#1
0
        /// <summary>
        /// Creates a new automation
        /// </summary>
        /// <param name="name">The friendly name of the automation</param>
        /// <param name="host">The host that manages this automation</param>
        protected Automation(string id, string name, IAutomationHost host)
        {
            Id        = id ?? name;
            Name      = name ?? throw new ArgumentNullException(nameof(name));
            Scheduler = host.Scheduler ?? throw new InvalidOperationException("Host's scheduler is 'null'.");

            _hostSubscription = Observable
                                .DeferAsync(async ct =>
            {
                await host.Initialized(ct, this);

                return(host.GetAndObserveIsEnabled(this));
            })
                                .DistinctUntilChanged()
                                .Do(isEnabled =>
            {
                // Make sure to always abort the pending execution, even if 'Enable()' fails
                _automationSubscription.Disposable = null;
                if (isEnabled)
                {
                    _automationSubscription.Disposable = new CompositeDisposable
                    {
                        // AsyncContext is used here mainly to propagate the IScheduler, but might flow in the subscriptions
                        // made in the "Enable". So we make sure to dispose it only when the automation is disable.
                        new AsyncContext(Scheduler),
                        Enable()
                    };
                }

                this.Log().Info($"Automation '{Name}' is now enabled: {isEnabled}");
            })
                                .Retry(Constants.DefaultRetryDelay, Scheduler)
                                .Subscribe();
        }
示例#2
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        /// <summary>
        /// Constructor sets up queue and creates download folder if non-existing.
        /// </summary>
        public JobManager(IDatabaseManager databaseManager, IMessageManager messageManager, IThreadManager threadManager, ILogger logger, CrashManager crashManager)
        {
            _databaseManager = databaseManager;
            _messageManager  = messageManager;
            _threadManager   = threadManager;
            _logger          = logger;
            _crashManager    = crashManager;

            // setup transfer queue
            _queue = _jobs
                     .Do(job => _logger.Info("----- Added job {0} to active transfers.", job.File.Name))
                     .ObserveOn(Scheduler.Default)
                     .Select(job => Observable.DeferAsync(async token => Observable.Return(await ProcessDownload(job, token))))
                     .Merge(MaximalSimultaneousDownloads)
                     .Subscribe(job => {
                _databaseManager.SaveJob(job);

                if (job.Status != Job.JobStatus.Aborted)
                {
                    _whenDownloaded.OnNext(job);
                }
            }, error => {
                // todo treat error in ui
                _logger.Error(error, "Error: {0}", error.Message);
            });

            // save job when status changes
            _whenStatusChanged.Sample(TimeSpan.FromMilliseconds(200)).Subscribe(_databaseManager.SaveJob);

            if (!Directory.Exists(_downloadPath))
            {
                _logger.Info("Creating non-existing download folder at {0}.", _downloadPath);
                Directory.CreateDirectory(_downloadPath);
            }
        }
示例#3
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            public IObservable <StatisticItem> GetStatisticItems()
            {
                if (null == task)
                {
                    task = provider.GetStatisticAsync(CancellationToken.None);
                }

                var observable = Observable.DeferAsync(
                    async cancellationToken =>
                {
                    var feed = await task;

                    return(Observable.Create <StatisticItem>(observer =>
                    {
                        foreach (var statisticItem in feed)
                        {
                            observer.OnNext(statisticItem);
                        }

                        observer.OnCompleted();

                        return Disposable.Create(() => task = null);
                    }));
                }
                    );

                return(observable);
            }
示例#4
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 /// <summary>
 /// サーバーへのリクエストの間隔が指定された時間を下回らないように、ブログエントリの一覧を非同期で取得します。
 /// </summary>
 /// <param name="period">サーバーへのリクエストの最小間隔。</param>
 /// <returns>ブログエントリの一覧を非同期で列挙する、 <see cref="IObservable{T}"/> 型の通知プロバイダー。</returns>
 /// <exception cref="ResourceNotFoundException">存在しないリソースにアクセスしました。</exception>
 /// <exception cref="InternalServerErrorException">はてなブログ AtomPub で問題が発生しました。</exception>
 /// <exception cref="HttpRequestException">HTTP リクエストに失敗しました。</exception>
 public IObservable <Entry> GetEntriesAsObservable(TimeSpan period)
 {
     return(Observable.DeferAsync(async ct =>
     {
         var requestUri = !_hasCurrentFeed ? _collectionUri : _currentFeed.NextRequestUri;
         var response = await _client.Value.GetAsync(requestUri, ct).ConfigureAwait(false);
         VerifyResponse(response);
         var stream = await response.Content.ReadAsStreamAsync().ConfigureAwait(false);
         var xElement = XElement.Load(stream);
         _currentFeed = Feed.FromXElement(xElement);
         _hasCurrentFeed = true;
         return Observable.Return(_currentFeed);
     })
            .TimeInterval()
            .Select(ti => Observable.FromAsync(async ct =>
     {
         Debug.WriteLine(ti.Interval);
         var delay = Extensions.Max(TimeSpan.Zero, period - ti.Interval);
         await Task.Delay(delay, ct).ConfigureAwait(false);
         return ti.Value;
     }))
            .Concat()
            .SelectMany(f => f)
            .DoWhile(() => _currentFeed.NextRequestUri != null)
            .Finally(() =>
     {
         _currentFeed = null;
         _hasCurrentFeed = false;
     }));
 }
示例#5
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        public FileWatchingDocument(IFileSystem fs, AbsoluteFilePath path, IScheduler scheduler = null)
        {
            _fs        = fs;
            _path      = path;
            _scheduler = scheduler ?? Scheduler.Default;

            var contents =
                fs.Watch(path)
                .StartWith(Unit.Default)
                .CatchAndRetry(delay: TimeSpan.FromSeconds(1), scheduler: _scheduler)
                .Throttle(TimeSpan.FromSeconds(1.0 / 30.0), _scheduler)
                .Select(
                    notifyTime => Observable.DeferAsync(
                        async token => Observable.Return(
                            await ReadAllBytesAndRetryOnError(token))))
                .Switch()
                .Replay(1);

            var externalChanges = contents
                                  .Where(bytes => _lastKnownChanges.Value.Select(bytes.SequenceEqual).Or(false) == false)
                                  .Do(bytes => _lastKnownChanges.OnNext(bytes))
                                  .Replay(1);

            _garbage = Disposable.Combine(
                externalChanges.Connect(),
                contents.Connect());

            Contents        = contents;
            ExternalChanges = externalChanges;
        }
示例#6
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        private static IObservable <bool> requestPermission(
            IObservable <bool> permissionChecker,
            Func <Task <Tuple <bool, NSError> > > permissionRequestFunction,
            bool force)
        => Observable.DeferAsync(async cancellationToken =>
        {
            var permissionGranted = await permissionChecker;

            if (permissionGranted)
            {
                return(Observable.Return(true));
            }

            if (force)
            {
                //Fact: If the user changes any permissions through the settings, this app gets restarted
                //and in that case we don't care about the value returned from this method.
                //We care about the returned value in the case, when user opens settings
                //and comes back to this app without altering any permissions. In that case
                //returning the current permission status is the correct behaviour.
                OpenAppSettings();
                return(Observable.Return(false));
            }

            return(Observable
                   .FromAsync(permissionRequestFunction)
                   .Select(tuple => tuple.Item1));
        });
示例#7
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        public void DeferAsync_WithCancel_Cancel()
        {
            var N = 10;// 0000;

            for (int i = 0; i < N; i++)
            {
                var e      = new ManualResetEvent(false);
                var called = false;

                var xs = Observable.DeferAsync <int>(ct => Task.Factory.StartNew(() =>
                {
                    e.Set();

                    while (!ct.IsCancellationRequested)
                    {
                        ;
                    }

                    return(Observable.Defer(() => { called = true; return Observable.Return(42); }));
                }));

                var d = xs.Subscribe(_ => { });

                e.WaitOne();
                d.Dispose();

                Assert.False(called);
            }
        }
示例#8
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        public static async Task LimitConcurrencyGoodExample()
        {
            var rng = new Random();

            await Observable
            .Range(1, 10, TaskPoolScheduler.Default)
            .Select(
                range =>
                Observable
                .DeferAsync(
                    async ct =>
            {
                WriteToConsoleWithColor((ConsoleColor)range, $"{range} - Started at {DateTimeOffset.Now.ToUnixTimeMilliseconds()}");
                var delay = rng.Next(10, 300);
                await Task.Delay(delay);

                WriteToConsoleWithColor((ConsoleColor)range, $"{range} - Finished after {delay}ms");

                return(Observable.Return(range));
            }))
            .Merge(1)
            .Do(
                range =>
            {
                WriteToConsoleWithColor((ConsoleColor)range, $"{range} - Received Notification at {DateTimeOffset.Now.ToUnixTimeMilliseconds()}");
            });
        }
示例#9
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        /// <summary>
        /// Creates a new automation
        /// </summary>
        /// <param name="name">The friendly name of the automation</param>
        /// <param name="host">The host that manages this automation</param>
        protected Automation(string id, string name, IAutomationHost host)
        {
            Id        = id ?? name;
            Name      = name ?? throw new ArgumentNullException(nameof(name));
            Scheduler = host.Scheduler ?? throw new InvalidOperationException("Host's scheduler is 'null'.");

            _hostSubscription = Observable
                                .DeferAsync(async ct =>
            {
                await host.Initialized(ct, this);

                return(host.GetAndObserveIsEnabled(this));
            })
                                .Do(isEnabled =>
            {
                // Make sure to always abort the pending execution, even if 'Enable()' fails
                _automationSubscription.Disposable = null;
                if (isEnabled)
                {
                    using (new AsyncContext(Scheduler))                             // AsyncContext is used here only to propagate the IScheduler
                    {
                        _automationSubscription.Disposable = Enable();
                    }
                }

                this.Log().Info($"Automation '{Name}' is now enabled: {isEnabled}");
            })
                                .Retry(Constants.DefaultRetryDelay, Scheduler)
                                .Subscribe();
        }
示例#10
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 public DeferByAsync()
 {
     Obs = Observable.Interval(TimeSpan.FromSeconds(3))
           .Select(item => Observable.DeferAsync(async token => {
         return(await ExpensiveTask(token, item));
     }))
           .Switch();
 }
 private IObservable <Unit> selectWorkspace(SelectableWorkspaceViewModel workspace)
 => Observable.DeferAsync(async _ =>
 {
     await interactorFactory.SetDefaultWorkspace(workspace.WorkspaceId).Execute();
     accessRestrictionStorage.SetNoDefaultWorkspaceStateReached(false);
     await navigationService.Close(this, Unit.Default);
     return(Observable.Return(Unit.Default));
 });
示例#12
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        public void DeferAsync_WithCancel_Simple()
        {
            var xs = Observable.DeferAsync <int>(ct => Task.Factory.StartNew(() => Observable.Return(42)));

            var res = xs.ToEnumerable().ToList();

            Assert.True(new[] { 42 }.SequenceEqual(res));
        }
 SideEffectLast <T>(this IObservable <T> source, Func <CancellationToken, Task> last) =>
 source
 .Concat(
     Observable.DeferAsync(
         async ct =>
 {
     await last(ct).ConfigureAwait(false);
     return(Observable.Empty <T>());
 }));
示例#14
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        public IObservable <Unit> DeleteMesh(string meshName, string resourceGroupName)
        {
            return(Observable.DeferAsync(async token =>
            {
                await _serviceFabricMeshManagementClient.Application.DeleteWithHttpMessagesAsync(
                    resourceGroupName,
                    meshName, cancellationToken: token);

                return Observable.Return(Unit.Default);
            }));
        }
示例#15
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 public static IObservable <TOut> OnEachExecuteCancellingPrevious <TIn, TOut>(this IObservable <TIn> This,
                                                                              Func <TIn, CancellationToken, Task <TOut> > func)
 {
     return
         (This
          .Select(item => Observable.DeferAsync(async token =>
     {
         var val = await func.Invoke(item, token);
         return Observable.Return(val);
     }))
          .Switch());
 }
示例#16
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        public static IObservable <T> DeferAndThrowIfPermissionNotGranted <T>(this IObservable <bool> permissionGrantedObservable, Func <IObservable <T> > implementation)
        => Observable.DeferAsync(async cancellationToken =>
        {
            var isAuthorized = await permissionGrantedObservable;
            if (!isAuthorized)
            {
                return(Observable.Throw <T>(
                           new NotAuthorizedException("You don't have permission to schedule notifications")
                           ));
            }

            return(implementation());
        });
 public IObservable <bool> GetDeferredObservable(object connection)
 {
     return(Observable.DeferAsync <bool>(token => {
         return Task.Factory.StartNew(() => {
             Console.WriteLine("UNDERLYING ENGAGED");
             Thread.Sleep(1000);
             // Let's pretend there's some static on the line...
             return Observable.Return(true)
             .Concat(Observable.Return(false))
             .Concat(Observable.Return(true));
         }, token);
     }));
 }
示例#18
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 /// <summary>
 /// Allows cancellation of a call to `selector` when the input observable produces a new value.
 /// </summary>
 /// <typeparam name="TIn"></typeparam>
 /// <typeparam name="TOut"></typeparam>
 /// <param name="o"></param>
 /// <param name="selector"></param>
 /// <returns></returns>
 public static IObservable <TOut> SelectAsync <TIn, TOut>(this IObservable <TIn> o, Func <TIn, CancellationToken, Task <TOut> > selector)
 {
     return(o
            .Select(x =>
                    Observable.DeferAsync(async ct =>
     {
         try
         {
             var result = await selector(x, ct);
             return Observable.Return(result);
         }
         catch (OperationCanceledException)
         {
             return Observable.Empty <TOut>();
         }
     })
                    )
            .Switch());
 }
示例#19
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        public IObservable <string> CreateOrEditMesh(string applicationResourceName, string imageRegistryServer,
                                                     string imageRegistryUsername, string imageRegistryPassword, string imageName, string azurePipelinesUrl,
                                                     string azurePipelinesToken, string resourceGroupName, int?replicaCount = null)
        {
            return(Observable.DeferAsync(async token =>
            {
                var applicationResourceDescription = CreateApplicationResourceDescription(imageRegistryServer,
                                                                                          imageRegistryUsername, imageRegistryPassword, imageName, azurePipelinesUrl, azurePipelinesToken,
                                                                                          replicaCount);

                var createMeshResponse =
                    await _serviceFabricMeshManagementClient.Application.CreateWithHttpMessagesAsync(
                        resourceGroupName,
                        applicationResourceName,
                        applicationResourceDescription,
                        cancellationToken: token);

                _logger.Verbose("CreateMeshResponse.Body {@ResponseBody}", createMeshResponse.Body);

                return Observable.Return(applicationResourceName);
            }).SubscribeOn(_schedulerProvider.TaskPool));
        }
示例#20
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        private IObservable <IList <IProject> > searchProjects(long workspaceId, long[] projectIds) =>
        Observable.DeferAsync(async cancellationToken =>
        {
            if (projectIds.Length == 0)
            {
                return(Observable.Return(new List <IProject>()));
            }

            var projectsInDatabase = await projectIds
                                     .Select(tryGetProjectFromDatabase)
                                     .Aggregate(Observable.Merge)
                                     .ToList();

            var notInDatabaseIds           = projectsInDatabase.SelectAllLeft().ToArray();
            var databaseProjectsObservable =
                Observable.Return(projectsInDatabase.SelectAllRight().ToList());

            return(notInDatabaseIds.Length == 0
                    ? databaseProjectsObservable
                    : databaseProjectsObservable
                   .Merge(searchMemoryAndApi(workspaceId, notInDatabaseIds))
                   .SelectMany(list => list)
                   .ToList());
        });
示例#21
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        public IObservable <object> GetTrigger(BlockConfig trigger, IFlowContext context)
        {
            try
            {
                var(connector, connection, name) = GetConnection(trigger, context);

                var flowTrigger = connector.GetTrigger(name);
                if (flowTrigger is null)
                {
                    throw new FlowException($"Unable to acquire trigger \"{trigger.Type}\".", context);
                }

                return(Observable.DeferAsync(async _ =>
                {
                    var flowTriggerConfiguration = await Resolve(trigger.Arguments, flowTrigger.ArgumentsType, context);

                    return flowTrigger.GetEvents(context, connection, flowTriggerConfiguration);
                }));
            }
            catch (Exception e) when(e is not FlowException)
            {
                throw new FlowException($"Error while getting trigger \"{trigger.Type}\".", context, e);
            }
        }
示例#22
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        ParserService(ITextBuffer textBuffer)
        {
            TextBuffer = textBuffer;

            WeakEventDispatcher.Connect(this, textBuffer);

            _parserObs = Observable.FromEventPattern <EventArgs>(
                handler => RebuildTriggered += handler,
                handler => RebuildTriggered -= handler)
                         .Select(_ => CreateBuildResultArgs())
                         .Throttle(ServiceProperties.ParserServiceThrottleTime)
                         .Select(args => Observable.DeferAsync(async token => {
                var parseResult = await BuildAsync(args, token).ConfigureAwait(false);

                return(Observable.Return(parseResult));
            }))
                         .Switch()
                         .ObserveOn(SynchronizationContext.Current)
                         .Subscribe(TrySetResult);

            _waitingForAnalysis = true;
            // Initiales Parsen antriggern
            Invalidate();
        }
示例#23
0
        public void DeferVsDeferAsyncTest()
        {
            const string NOT_AUTH = "not authenticate";

            var xs = Observable.Interval(TimeSpan.FromSeconds(0.5))
                     .Take(20)
                     .Publish(); // convert into hot observable

            xs.Monitor("Source", 1).Subscribe();
            xs.Connect();

            var ds = Observable.Defer(() => xs);

            ds = ds.Monitor("Defer", 2);

            var ds1 = Observable.DeferAsync <long>((ct) =>
            {
                return(Task.Factory.StartNew(() =>
                {
                    if (Authenticate("user", ct))
                    {
                        return xs;
                    }
                    else
                    {
                        return Observable.Throw <long>(new SecurityException("not authenticate"));
                    }
                }));
            });

            ds1 = ds1.Monitor("Defer Async User", 3);

            var ds2 = Observable.DeferAsync <long>((ct) =>
            {
                return(Task.Factory.StartNew(() =>
                {
                    if (Authenticate("admin", ct))
                    {
                        return xs;
                    }
                    else
                    {
                        return Observable.Throw <long>(new SecurityException(NOT_AUTH));
                    }
                }));
            });

            ds2 = ds2.Monitor("Defer Async Admin", 4);

            ds.Subscribe();
            ds1.Subscribe();
            ds2.Subscribe();

            try
            {
                ds.Wait();
                ds1.Wait();
                ds2.Wait();
            }

            #region Exception Handling

            catch (SecurityException ex)
            {
                Assert.AreEqual(NOT_AUTH, ex.Message);
            }

            #endregion Exception Handling
        }
        public (IObservable <Unit> request, IObservable <bool> ready, Func <(IObservable <Unit> request, IObservable <Unit> complete)> stop) Start(string applicationResourceName,
                                                                                                                                                   string imageRegistryServer,
                                                                                                                                                   string imageRegistryUsername, string imageRegistryPassword, string imageName, string azurePipelinesUrl,
                                                                                                                                                   string azurePipelinesToken, string resourceGroupName,
                                                                                                                                                   bool outputContainerLogs = true, bool outputComponentStatus = true)
        {
            var autoResetEvent = new AutoResetEvent(false);
            var disposable     = new CompositeDisposable();
            var readySubject   = new Subject <bool>();
            var request        = Observable.DeferAsync(async token =>
            {
                _logger.Information("Starting Mesh {Mesh}", applicationResourceName);

                await _observableMeshClient.CreateOrEditMesh(applicationResourceName, imageRegistryServer,
                                                             imageRegistryUsername, imageRegistryPassword, imageName, azurePipelinesUrl, azurePipelinesToken,
                                                             resourceGroupName);

                var startPollingSubject    = new Subject <Unit>();
                var startPollingObservable = startPollingSubject.AsObservable();

                var applicationFailedSubject    = new Subject <Unit>();
                var applicationFailedObservable = applicationFailedSubject.AsObservable();

                var pollApplicationStatus = _observableMeshClient
                                            .PollApplicationStatus(applicationResourceName, resourceGroupName)
                                            .Replay();

                var pollServiceStatus = _observableMeshClient
                                        .PollServiceStatus(applicationResourceName, resourceGroupName, startPollingObservable, applicationFailedObservable)
                                        .Replay();

                var pollAgentStatus = _observableMeshClient
                                      .PollAgentStatus(applicationResourceName, resourceGroupName, startPollingObservable, applicationFailedObservable, 0, outputContainerLogs)
                                      .Replay();

                var pollReplicaStateSubscription = pollAgentStatus
                                                   .SubscribeOn(_schedulerProvider.TaskPool)
                                                   .Subscribe(agentStateEnum => { },
                                                              exception => { _logger.Error("Container Logs Error: {Message}", exception.Message); });

                var applicationStateObservable = pollApplicationStatus
                                                 .SubscribeOn(_schedulerProvider.TaskPool)
                                                 .Subscribe(applicationStatusEnum => { },
                                                            exception =>
                {
                    _logger.Error("Application Error: {Message}", exception.Message);
                });

                var serviceDataSubscription = pollServiceStatus
                                              .SubscribeOn(_schedulerProvider.TaskPool)
                                              .Subscribe(serviceStatusEnum => { },
                                                         exception =>
                {
                    _logger.Error("Service Error: {Message}", exception.Message);
                });

                var combinedSubscription = pollApplicationStatus.CombineLatest(pollServiceStatus, pollAgentStatus,
                                                                               (applicationStatus, serviceStatus, agentStatus) =>
                                                                               (applicationStatus, serviceStatus, agentStatus))
                                           .DistinctUntilChanged()
                                           .SubscribeOn(_schedulerProvider.TaskPool)
                                           .Subscribe(tuple =>
                {
                    var(applicationStatus, serviceStatus, agentStatus) = tuple;

                    if (outputComponentStatus)
                    {
                        _logger.Information(
                            "Mesh {Mesh} Application {Application,8} Service {Service,8} Agent {Agent,8}",
                            applicationResourceName, applicationStatus, serviceStatus, agentStatus);
                    }

                    if (applicationStatus == ApplicationStatusEnum.Ready &&
                        serviceStatus == ServiceStatusEnum.Ready &&
                        agentStatus == AgentStatusEnum.Ready)
                    {
                        readySubject.OnNext(true);
                        readySubject.OnCompleted();
                        return;
                    }

                    if (applicationStatus == ApplicationStatusEnum.Failed &&
                        serviceStatus == ServiceStatusEnum.Failed &&
                        agentStatus == AgentStatusEnum.Failed)
                    {
                        readySubject.OnNext(false);
                        readySubject.OnCompleted();
                        return;
                    }

                    if (applicationStatus == ApplicationStatusEnum.Failed)
                    {
                        applicationFailedSubject.OnNext(Unit.Default);
                        applicationFailedSubject.OnCompleted();
                        return;
                    }

                    if (applicationStatus == ApplicationStatusEnum.Creating)
                    {
                        startPollingSubject.OnNext(Unit.Default);
                        startPollingSubject.OnCompleted();
                        return;
                    }
                },
                                                      () =>
                {
                    _logger.Debug("Streams completed");
                    autoResetEvent.Set();
                });

                pollApplicationStatus.Connect();
                pollServiceStatus.Connect();
                pollAgentStatus.Connect();

                disposable.Add(pollReplicaStateSubscription);
                disposable.Add(applicationStateObservable);
                disposable.Add(serviceDataSubscription);
                disposable.Add(combinedSubscription);
                disposable.Add(readySubject);
                disposable.Add(startPollingSubject);
                disposable.Add(applicationFailedSubject);

                return(Observable.Return(Unit.Default));
            }).SubscribeOn(_schedulerProvider.TaskPool);

            Func <(IObservable <Unit> request, IObservable <Unit> complete)> stop = () =>
            {
                var completeObservable = Observable.Defer(() =>
                {
                    autoResetEvent.WaitOne();

                    _logger.Information("Stopped");

                    disposable.Dispose();
                    disposable = null;

                    return(Observable.Return(Unit.Default));
                }).SubscribeOn(_schedulerProvider.TaskPool);
                ;

                var stopRequest = Observable.DeferAsync(async token =>
                {
                    _logger.Information("Stopping");

                    await _observableMeshClient.DeleteMesh(applicationResourceName, resourceGroupName);

                    return(Observable.Return(Unit.Default));
                }).SubscribeOn(_schedulerProvider.TaskPool);

                return(stopRequest, completeObservable);
            };

            var ready = readySubject.AsObservable();

            return(request, ready, stop);
        }
示例#25
0
 public void DeferAsync_ArgumentChecking()
 {
     ReactiveAssert.Throws <ArgumentNullException>(() => Observable.Defer(default(Func <Task <IObservable <int> > >)));
     ReactiveAssert.Throws <ArgumentNullException>(() => Observable.DeferAsync(default(Func <CancellationToken, Task <IObservable <int> > >)));
 }