// at least once delivery check
async Task AtLeastOnceDeliveryExample()
{
var hub = new MetaPubSub();
var message = new MyMessage
{
// if this not set, NoSubscribersException will not be thrown
DeliverAtLeastOnce = true
};
try
{
// publishing a message when no one is subscribed
await hub.Publish(message);
}
catch (NoSubscribersException ex)
{
// no one is listening
Console.WriteLine($"Exception {ex.GetType()}: {ex.Message}");
}
hub.Subscribe <MyMessage>(OnMyMessage);
await hub.Publish(message);
await hub.Unsubscribe <MyMessage>(OnMyMessage);
}
public void SetDevice(IDevice device)
{
_device = device;
_device.ConnectionStateChanged += (object sender, EventArgs e) =>
{
try
{
if (!IsConnected && CurrentState == State.Wiping)
{
CurrentState = State.Success;
_hub.Publish(new DeviceWipedEvent(this));
}
NotifyPropertyChanged(nameof(IsConnected));
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
};
_device.PropertyChanged += (object sender, string e) =>
{
NotifyPropertyChanged(e);
};
NotifyPropertyChanged(nameof(SerialNo));
}
void ConnectionManager_AdvertismentReceived(object sender, AdvertismentReceivedEventArgs e)
{
if (e.Rssi > SdkConfig.TapProximityUnlockThreshold)
{
_hub.Publish(new AdvertismentReceivedEvent(e));
}
}
// subscribed twice but delivered only once
public async Task Basic()
{
var hub = new MetaPubSub();
await Task.Run(() =>
{
for (int i = 0; i < 10_000; i++)
{
var subscriber = new MySubscriber();
//await Task.Delay(50);
hub.Subscribe <MyMessage>(subscriber.Handler);
}
});
int totalDeliveryCount1 = 0;
var t1 = Task.Run(async() =>
{
for (int i = 0; i < 1000; i++)
{
var subscriber = new MySubscriber();
hub.Subscribe <MyEvent>(subscriber.Handler);
var message = new MyMessage();
await hub.Publish(message);
totalDeliveryCount1 += message.DeliveredCount;
await hub.Unsubscribe <MyEvent>(subscriber.Handler);
}
});
int totalDeliveryCount2 = 0;
var t2 = Task.Run(async() =>
{
for (int i = 0; i < 1000; i++)
{
var subscriber = new MySubscriber();
hub.Subscribe <MyMessage>(subscriber.Handler);
var message = new MyMessage();
await hub.Publish(message);
totalDeliveryCount2 += message.DeliveredCount;
await hub.Unsubscribe <MyMessage>(subscriber.Handler);
}
});
await Task.WhenAll(t1, t2);
Assert.IsTrue(totalDeliveryCount1 > (10_000 * 1000) && totalDeliveryCount1 < (10_000 * 1000 + 1000));
Assert.IsTrue(totalDeliveryCount2 == 10_000 * 1000 + 1000);
}
// same as previous but should not deliver the message
// because the second subscriber has also the same filter
public async Task Test_DeliverAtLeastOnce_Delayed2()
{
var hub = new MetaPubSub();
bool timeoutException = false;
// first subscriber which will not process the message due to its filter
hub.Subscribe <MyMessage>(OnMyMessageHandler, OnMyMessagePredicate);
// second subscriber which will subscribe after the message has been published
var t = Task.Run(async() =>
{
await Task.Delay(50);
hub.Subscribe <MyMessage>(OnMyMessageHandler2, OnMyMessagePredicate);
await hub.Unsubscribe <MyMessage>(OnMyMessageHandler2);
});
var message = new MyMessage {
LogSeverity = MetaLogErrorSeverity.Info, DeliverAtLeastOnce = true, WaitForSubscriberTimeout = 100
};
try
{
// the message has a timeout and can wait until the second subscriber come
await hub.Publish(message);
}
catch (TimeoutException)
{
timeoutException = true;
}
Assert.IsTrue(timeoutException);
Assert.IsTrue(message.DeliveredCount == 0);
await hub.Unsubscribe <MyMessage>(OnMyMessageHandler);
}
// cancellation token support - you can cancel scheduling or waiting for the message
public static async Task CancellationExample()
{
var hub = new MetaPubSub();
var cts = new CancellationTokenSource();
// publish an event after 100 ms
var t = Task.Run(async() =>
{
await Task.Delay(100);
await hub.Publish(new MyEvent());
});
// cancel waiting after 50 ms
var t2 = Task.Run(async() =>
{
await Task.Delay(50);
cts.Cancel();
});
try
{
var res = await hub.When <MyEvent>(millisecondsTimeout : 200, match : null, cts.Token);
}
catch (OperationCanceledException)
{
Console.WriteLine("Waiting for MyEvent has been canceled");
}
}
public async Task Test_When()
{
var hub = new MetaPubSub();
var t = Task.Run(async() =>
{
await Task.Delay(50);
await hub.Publish(new MyEvent());
});
var res = await hub.When <MyEvent>(100);
Assert.IsNotNull(res);
bool timeoutException = false;
try
{
res = await hub.When <MyEvent>(100);
}
catch (TimeoutException)
{
timeoutException = true;
}
Assert.IsTrue(timeoutException);
}
public async Task Test_Cancel_When()
{
var hub = new MetaPubSub();
var cts = new CancellationTokenSource();
// publish an event after 100 ms
var t = Task.Run(async() =>
{
await Task.Delay(100);
await hub.Publish(new MyEvent());
});
// cancel waiting after 50 ms
var t2 = Task.Run(async() =>
{
await Task.Delay(50);
cts.Cancel();
});
bool exception = false;
try
{
var res = await hub.When <MyEvent>(200, null, cts.Token);
Assert.IsTrue(false);
}
catch (OperationCanceledException)
{
exception = true;
}
Assert.IsTrue(exception);
}
// timeout to wait for a subscriber - your message can be queued and wait until someone subscribed and processed it
public async Task DeliverAtLeastOnceDelayedExample()
{
var hub = new MetaPubSub();
// a subscriber that will subscribe after the message has been published
var t = Task.Run(async() =>
{
await Task.Delay(1500);
Console.WriteLine($"Subscribed to MyMessage at {DateTime.Now:HH:mm:ss.fff}");
hub.Subscribe <MyMessage>(OnMyMessage);
});
// the message has the 10 seconds timeout and can wait until the subscriber come
var message = new MyMessage
{
DeliverAtLeastOnce = true, // this must be set to true
WaitForSubscriberTimeout = 10_000
};
Console.WriteLine($"Start publishing and awaiting at {DateTime.Now:HH:mm:ss.fff}");
// this method will wait until the subscriber receives the message or until timeout expired (10 seconds)
await hub.Publish(message);
Console.WriteLine($"End awaiting at {DateTime.Now:HH:mm:ss.fff}");
await hub.Unsubscribe <MyMessage>(OnMyMessage);
}
protected override async void OnClosing(CancelEventArgs e)
{
var vm = (MainWindowViewModel)DataContext;
if (vm.IsFirmwareUpdateInProgress)
{
var mb = MessageBox.Show(
"Firmware update in progress!" +
Environment.NewLine +
"Are you sure you want to exit?",
"Exit application",
MessageBoxButton.YesNoCancel,
MessageBoxImage.Exclamation);
if (mb != MessageBoxResult.Yes)
{
e.Cancel = true;
return;
}
}
try
{
await _hub.Publish(new ClosingEvent());
base.OnClosing(e);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "Error",
MessageBoxButton.OK, MessageBoxImage.Error);
e.Cancel = true;
}
}
// Should deliver if message is filtered at first and DeliverAtLeastOnce = true but Timeout > 0 and
// after the message has published a new subscriber arrived
public async Task Test_DeliverAtLeastOnce_Delayed()
{
var hub = new MetaPubSub();
// first subscriber which will not process the message due to its filter
hub.Subscribe <MyMessage>(OnMyMessageHandler, OnMyMessagePredicate);
// second subscriber which will subscribe after the message has been published
// also with filter, will not process the message
var t = Task.Run(async() =>
{
await Task.Delay(50);
hub.Subscribe <MyMessage>(OnMyMessageHandler2, OnMyMessagePredicate);
});
// third subscriber which will subscribe after the message has been published
var t2 = Task.Run(async() =>
{
await Task.Delay(70);
hub.Subscribe <MyMessage>(OnMyMessageHandler3);
});
var message = new MyMessage {
LogSeverity = MetaLogErrorSeverity.Info, DeliverAtLeastOnce = true, WaitForSubscriberTimeout = 200000
};
// the message has a timeout and can wait until the second subscriber come
await hub.Publish(message);
Assert.IsTrue(message.DeliveredCount == 1);
await hub.Unsubscribe <MyMessage>(OnMyMessageHandler);
//hub.Unsubscribe<MyMessage>(OnMyMessageHandler2);
//hub.Unsubscribe<MyMessage>(OnMyMessageHandler3);
}
static async Task OnPing(PingCommand ping)
{
logger.Info($"ping {ping.Id}");
await hub.Publish(new PingReplay()
{
Id = ping.Id
});
}
public async Task Predicate()
{
var hub = new MetaPubSub();
hub.Subscribe <MyMessage>(OnMyMessageHandler, OnMyMessagePredicate);
var message = new MyMessage {
LogSeverity = MetaLogErrorSeverity.Info
};
await hub.Publish(message);
Assert.IsTrue(message.DeliveredCount == 0);
message = new MyMessage {
LogSeverity = MetaLogErrorSeverity.Error
};
await hub.Publish(message);
Assert.IsTrue(message.DeliveredCount == 1);
await hub.Unsubscribe <MyMessage>(OnMyMessageHandler);
}
async Task BasicExample()
{
// hub creation
var hub = new MetaPubSub();
// subscribing to MyMessage
hub.Subscribe <MyMessage>(OnMyMessage);
// publishing a message
await hub.Publish(new MyMessage());
// unsubscribing
await hub.Unsubscribe <MyMessage>(OnMyMessage);
}
// subscribes on server and receives a message
public async Task SendMessageToClient()
{
var pipeName = Guid.NewGuid().ToString();
var clientConnectedEvent = new ManualResetEventSlim();
var @event = new ManualResetEventSlim();
int recvCount = 0;
Task Handler(MyMessage x)
{
if (++recvCount == 10)
{
@event.Set();
}
return(Task.CompletedTask);
}
// creating remote hub
var t = Task.Run(async() =>
{
var hub = new MetaPubSub();
hub.StartServer(pipeName);
// wait for the subscriber
clientConnectedEvent.Wait(5000);
// publishing a message at the remote hub
for (int i = 0; i < 10; i++)
{
await hub.Publish(new MyMessage());
}
});
// local hub creation
var hub = new MetaPubSub();
await hub.ConnectToServer(pipeName);
await hub.SubscribeOnServer <MyMessage>(Handler);
// delay allowing the server to process the subscription request
await Task.Delay(100);
clientConnectedEvent.Set();
@event.Wait(5000);
// unsubscribing
await hub.Unsubscribe <MyMessage>(Handler);
Assert.IsTrue(@event.IsSet && recvCount == 10);
}
// message filtering - you can define a predicate to subscribe only those messages you want to process
async Task MessageFilteringExample()
{
var hub = new MetaPubSub();
// subscribing to MyMessage with a predicate that selects only error and critical messages
hub.Subscribe <MyMessage>(OnMyMessage, m =>
m.LogSeverity == MetaLogErrorSeverity.Error ||
m.LogSeverity == MetaLogErrorSeverity.Critical);
// this message will be filtered and not handled
var message1 = new MyMessage
{
LogSeverity = MetaLogErrorSeverity.Info
};
await hub.Publish(message1);
// this message will be handled
var message2 = new MyMessage
{
LogSeverity = MetaLogErrorSeverity.Error
};
await hub.Publish(message2);
}
// subscribed twice but delivered only once
public async Task Basic()
{
var hub = new MetaPubSub();
var message = new MyMessage();
await hub.Publish(message);
Assert.IsTrue(message.DeliveredCount == 0);
hub.Subscribe <MyMessage>(OnMyMessageHandler);
hub.Subscribe <MyMessage>(OnMyMessageHandler);
message = new MyMessage();
await hub.Publish(message);
Assert.IsTrue(message.DeliveredCount == 1);
await hub.Unsubscribe <MyMessage>(OnMyMessageHandler);
message = new MyMessage();
await hub.Publish(message);
Assert.IsTrue(message.DeliveredCount == 0);
}
// exceptions handling - all exceptions raised when a message processing by subscribers can be caught by the publisher as an AggregateException
async Task ExceptionHandlingExample()
{
var hub = new MetaPubSub();
try
{
var message = new MyMessage
{
DeliverAtLeastOnce = true,
};
// publishing a message when no one subscribed - NoSubscribersException
//await hub.Publish(message);
// publishing a message when no one subscribed and Timeout > 0 - TimeoutException
//message.Timeout = 100;
//await hub.Publish(message);
hub.Subscribe <MyMessage>(OnMyMessageHandlerWithException);
// publishing a message
await hub.Publish(message);
}
catch (NoSubscribersException ex)
{
// No one is subscribed to this message and (message.DeliverAtLeastOnce == true and message.Timeout == 0)
Console.WriteLine($"Exception {ex.GetType()}: {ex.Message}");
}
catch (TimeoutException ex)
{
// No one is subscribed to this message and (message.DeliverAtLeastOnce == true and message.Timeout > 0)
Console.WriteLine($"Exception {ex.GetType()}: {ex.Message}");
}
catch (AggregateException ex)
{
// All exceptions raised when a message processing by subscribers
// can be caught by the publisher as an AggregateException.
// If some of the subscribers throw an exception, other subscribers
// continues to process the message.
Console.WriteLine($"Exception {ex.GetType()}: {ex.Message}");
foreach (var innerEx in ex.InnerExceptions)
{
Console.WriteLine($"\tInner Exception {innerEx.GetType()}: {innerEx.Message}");
}
}
await hub.Unsubscribe <MyMessage>(OnMyMessageHandlerWithException);
}
public async Task Test_MultiProcess()
{
var hub = new MetaPubSub();
Task Handler(MyMessage x)
{
hub.Publish(new MyEvent()
{
SomeId = x.SomeId
});
return(Task.CompletedTask);
}
hub.Subscribe <MyMessage>(Handler);
var t1 = Task.Run(async() =>
{
for (int i = 0; i < 100; i++)
{
var message = new MyMessage
{
SomeId = i,
ResponseTimeout = 1000
};
var res = await hub.Process <MyEvent>(message, x => x.SomeId == i);
Assert.IsNotNull(res);
Assert.IsTrue(res.SomeId == i);
}
});
var t2 = Task.Run(async() =>
{
for (int i = 100; i < 200; i++)
{
var message = new MyMessage
{
SomeId = i,
ResponseTimeout = 1000
};
var res = await hub.Process <MyEvent>(message, x => x.SomeId == i);
Assert.IsNotNull(res);
Assert.IsTrue(res.SomeId == i);
}
});
await Task.WhenAll(t1, t2);
}
void SelectFirmware()
{
OpenFileDialog ofd = new OpenFileDialog
{
InitialDirectory = string.IsNullOrWhiteSpace(FirmwareFilePath) ? string.Empty : Path.GetDirectoryName(FirmwareFilePath),
Filter = "Firmware Image file | *.img"
};
if (ofd.ShowDialog() == true)
{
FirmwareFilePath = ofd.FileName;
}
if (IsFirmwareSelected)
{
_hub.Publish(new StartDiscoveryCommand());
}
}
public async Task Test_Process()
{
var hub = new MetaPubSub();
Task Handler(MyMessage x)
{
hub.Publish(new MyEvent());
return(Task.CompletedTask);
}
hub.Subscribe <MyMessage>(Handler);
var message = new MyMessage {
LogSeverity = MetaLogErrorSeverity.Info, DeliverAtLeastOnce = true, Timeout = 100
};
var res = await hub.Process <MyEvent>(message, 100);
Assert.IsNotNull(res);
}
async Task BasicExample()
{
int count = 0;
Task Handler(MyMessage x)
{
count++;
return(Task.CompletedTask);
}
// Creating the server hub.
// The server and the client hubs should be created in separate processes,
// this example is for demo only.
var serverHub = new MetaPubSub();
// Starting the hub as a server named 'Meta'.
serverHub.StartServer("Meta");
// Client hub creation. There are can be several hubs connected to the same server.
var clientHub = new MetaPubSub();
// Connecting to the remote server.
await clientHub.ConnectToServer("Meta");
// Subscribing to MyMessage on the server and locally at the same time.
await clientHub.SubscribeOnServer <MyMessage>(Handler);
// The server publishes a message.
await serverHub.Publish(new MyMessage());
// Client hub publishes a message and it will be received locally without being sent to the server.
await clientHub.Publish(new MyMessage());
// Client hub sends a message to the server where it will be published and sent back.
await clientHub.PublishOnServer(new MyMessage());
// All three messages should be received.
Debug.Assert(count == 3);
// Unsubscribing both on the server-side and locally.
await clientHub.Unsubscribe <MyMessage>(Handler);
}
public async Task NoSubscribersException()
{
var pipeName = Guid.NewGuid().ToString();
var clientConnectedEvent = new ManualResetEventSlim();
var @event = new ManualResetEventSlim();
// creating remote hub
var t = Task.Run(async() =>
{
var hub = new MetaPubSub();
hub.StartServer(pipeName);
// wait for the subscriber
clientConnectedEvent.Wait(5000);
try
{
// publishing a message at the remote hub
await hub.Publish(new MyMessage()
{
DeliverAtLeastOnce = true
});
}
catch (NoSubscribersException)
{
@event.Set();
}
});
// local hub creation
var hub = new MetaPubSub();
await hub.ConnectToServer(pipeName);
// delay allowing the server process the connection
await Task.Delay(100);
clientConnectedEvent.Set();
@event.Wait(5000);
Assert.IsTrue(@event.IsSet);
}
// request-response pattern - send a message and wait for the response as a single awaitable method, without need to Subscribe/Unsubscribe to the response message
public static async Task ProcessExample()
{
var hub = new MetaPubSub();
// This handler should be placed somewhere in another module.
// It processes MyMessage and publishes a MyEvent as a result.
Task Handler(MyMessage x)
{
hub.Publish(new MyEvent());
return(Task.CompletedTask);
}
hub.Subscribe <MyMessage>(Handler);
try
{
// This method will publish MyMessage and wait for MyEvent one second.
// If the event will not arrive in a specified timeout the TimeoutException will be thrown.
var message = new MyMessage
{
DeliverAtLeastOnce = true,
WaitForSubscriberTimeout = 100,
ResponseTimeout = 1_000
};
MyEvent res = await hub.Process <MyEvent>(message);
Console.WriteLine($"Received MyEvent at {DateTime.Now:HH:mm:ss.fff}");
}
catch (NoSubscribersException ex)
{
// no one is listening
Console.WriteLine($"Exception {ex.GetType()}: {ex.Message}");
}
catch (TimeoutException ex)
{
Console.WriteLine($"Exception {ex.GetType()}: {ex.Message}");
}
}
public async Task Test_Process()
{
var hub = new MetaPubSub();
Task Handler(MyMessage x)
{
Task.Run(async() =>
{
await Task.Delay(10);
await hub.Publish(new MyEvent());
});
return(Task.CompletedTask);
}
hub.Subscribe <MyMessage>(Handler);
var message = new MyMessage {
ResponseTimeout = 2000
};
var res = await hub.Process <MyEvent>(message);
Assert.IsNotNull(res);
}
// Should get the NoSubscribersException if message is filtered and DeliverAtLeastOnce = true
public async Task Test_DeliverAtLeastOnce_Filtered()
{
var hub = new MetaPubSub();
bool noSubscriberException = false;
hub.Subscribe <MyMessage>(OnMyMessageHandler, OnMyMessagePredicate);
var message = new MyMessage {
LogSeverity = MetaLogErrorSeverity.Info, DeliverAtLeastOnce = true
};
try
{
await hub.Publish(message);
}
catch (NoSubscribersException)
{
noSubscriberException = true;
}
Assert.IsTrue(noSubscriberException);
Assert.IsTrue(message.DeliveredCount == 0);
await hub.Unsubscribe <MyMessage>(OnMyMessageHandler);
}
// asynchronous waiting for a specified message by a single method call, without need to Subscribe/Unsubscribe to this message
public static async Task WhenExample()
{
var hub = new MetaPubSub();
// publishing a MyEvent with 500 ms delay
var t = Task.Run(async() =>
{
await Task.Delay(500);
await hub.Publish(new MyEvent());
});
try
{
// This method will wait for MyEvent one second.
// If the event will not arrive in a specified timeout the TimeoutException will be thrown.
MyEvent res = await hub.When <MyEvent>(millisecondsTimeout : 1000);
Console.WriteLine($"Received MyEvent at {DateTime.Now:HH:mm:ss.fff}");
}
catch (TimeoutException ex)
{
Console.WriteLine($"Exception {ex.GetType()}: {ex.Message}");
}
}
public MainWindowViewModel(MetaPubSub hub)
{
// default value -33 is to much and picks up devices from very far
SdkConfig.TapProximityUnlockThreshold = -29;
SdkConfig.ConnectDeviceTimeout = 5_000;
SdkConfig.DeviceInitializationTimeout = 5_000;
_hub = hub;
_log = new EventLogger("Maintenance");
_hub.Subscribe <AdvertismentReceivedEvent>(OnAdvertismentReceived);
_hub.Subscribe <DeviceConnectedEvent>(OnDeviceConnected);
_hub.Subscribe <ClosingEvent>(OnClosing);
ConnectionManager = new ConnectionManagerViewModel(_log, _hub);
HideezServiceController = new HideezServiceController(_log, _hub);
SystemEvents.SessionSwitch += SystemEvents_SessionSwitch;
if (IsFirmwareSelected)
{
_hub.Publish(new StartDiscoveryCommand());
}
}