static async Task TryWebSockets()
{
// Establish a TCP connection with the STOMP service.
using (ClientWebSocket webSocket = new ClientWebSocket())
{
await webSocket.ConnectAsync(new Uri("ws://52.137.87.113:15674/ws"), CancellationToken.None);
//Create a connector.
using (IStompConnector stompConnector =
new Stomp12Connector(
new WebSocketTransport(webSocket),
"WebChannel",
"",
""))
{
// Create a connection.
IStompConnection connection = await stompConnector.ConnectAsync();
// Send a message.
await connection.SendAsync("/queue/example4", "Anybody there!?");
await connection.SubscribeAsync(
new ConsoleWriterObserver(),
"/queue/example4");
// Wait for messages to be received.
await Task.Delay(250);
// Disconnect.
await connection.DisconnectAsync();
}
}
}
/// <summary>
/// This example will demonstrate the thread-safety of IStompConnector
/// </summary>
/// <returns></returns>
public static async Task ExampleConnectorConcurrent()
{
using (TcpClient tcpClient = new TcpClient(serverHostname, serverPort))
using (IStompConnector stompConnector = new Stomp12Connector(tcpClient.GetStream(), virtualHost, login, passcode))
{
IStompConnection connection = await stompConnector.ConnectAsync();
// Create threads to send messages.
ICollection <Thread> threads = new Collection <Thread>();
for (int i = 0; i < 10; i++)
{
Thread t = new Thread(
async() =>
{
for (int j = 0; j < 100; j++)
{
await connection.SendAsync(aQueueName, messageContent);
}
});
threads.Add(t);
}
// Start threads
foreach (Thread t in threads)
{
t.Start();
}
// Subscribe
IDisposable subscription =
await connection.SubscribeAsync(
new CounterObserver(), // An observer that count messages and print the count on completed.
aQueueName,
StompAckValues.AckClientIndividualValue); // Messages must be acked before the broker discards them.
Console.WriteLine("Please wait a few seconds...");
Console.WriteLine();
// Wait for the threads to finish.
foreach (Thread t in threads)
{
t.Join();
}
// Wait for a little longer for messages to arrive.
await Task.Delay(3000);
// Unsubscribe.
// After this invocation, observers's OnCompleted is going to be called.
// For this example, a count of 1000 should be shown unless there was
// previous data in the queue.
subscription.Dispose();
// Disconnect.
await connection.DisconnectAsync();
}
}
/// <summary>
/// Example used in the README.md file.
/// </summary>
static async Task ReadmeExample()
{
// Establish a TCP connection with the STOMP service.
using (TcpClient tcpClient = new TcpClient())
{
await tcpClient.ConnectAsync("localhost", 61613);
//Create a connector.
using (IStompConnector stompConnector =
new Stomp12Connector(
tcpClient.GetStream(),
"localhost", // Virtual host name.
"admin",
"password"))
{
// Create a connection.
IStompConnection connection = await stompConnector.ConnectAsync();
// Send a message.
await connection.SendAsync("/queue/example", "Anybody there!?");
// Send two messages using a transaction.
IStompTransaction transaction = await connection.BeginTransactionAsync();
await transaction.SendAsync("/queue/example", "Hi!");
await transaction.SendAsync("/queue/example", "My name is StompNet");
await transaction.CommitAsync();
// Receive messages back.
// Message handling is made by the ConsoleWriterObserver instance.
await transaction.SubscribeAsync(
new ConsoleWriterObserver(),
"/queue/example");
// Wait for messages to be received.
await Task.Delay(250);
// Disconnect.
await connection.DisconnectAsync();
}
}
}
static async Task ReadmeExample()
{
// Establish a TCP connection with the STOMP service.
using (TcpClient tcpClient = new TcpClient())
{
await tcpClient.ConnectAsync("", 15674);
//Create a connector.
using (IStompConnector stompConnector =
new Stomp12Connector(
tcpClient.GetStream(),
"WebChannel",
"",
""))
{
// Create a connection.
IStompConnection connection = await stompConnector.ConnectAsync();
// Send a message.
await connection.SendAsync("/queue/example", "Anybody there!?");
// Send two messages using a transaction.
IStompTransaction transaction = await connection.BeginTransactionAsync();
await transaction.SendAsync("/queue/example", "Hi!");
await transaction.SendAsync("/queue/example", "My name is StompNet");
await transaction.CommitAsync();
await transaction.SubscribeAsync(
new ConsoleWriterObserver(),
"/queue/example");
// Wait for messages to be received.
await Task.Delay(250);
// Disconnect.
await connection.DisconnectAsync();
}
}
}
/// <summary>
/// Example to demonstrate STOMP transactions using the StompNet high level API.
///
/// BEWARE: APACHE APOLLO DOES NOT HANDLE VERY MELL TRANSACTION WITH RECEIPT CONFIRMATIONS.
/// </summary>
public static async Task ExampleConnectorTransaction()
{
using (TcpClient tcpClient = new TcpClient(serverHostname, serverPort))
using (IStompConnector stompConnector = new Stomp12Connector(tcpClient.GetStream(), virtualHost, login, passcode))
{
IStompConnection connection = await stompConnector.ConnectAsync();
//
// TRANSACTION 1
// This transaction send two messages to a queue.
//
Console.WriteLine("TRANSACTION #1");
IStompTransaction tr1 = await connection.BeginTransactionAsync();
await tr1.SendAsync(aQueueName, messageContent + " #1");
await tr1.SendAsync(aQueueName, messageContent + " #2");
await tr1.CommitAsync();
Console.WriteLine("Messages sent to queue: " + aQueueName + ".");
Console.WriteLine();
//
// TRANSACTION 2
// Transactionally receive messages from a queue and send rhem to another queue.
//
Console.WriteLine("TRANSACTION #2");
IAsyncDisposable sub2 =
await connection.SubscribeAsync(
new TransactionalObserver(connection, "#2"), //The transaction is done inside the observer.
aQueueName,
StompAckValues.AckClientIndividualValue,
true);
// Wait some time for the messages to be received and processed.
await Task.Delay(500);
await sub2.DisposeAsync();
Console.WriteLine("Messages processed from " + aQueueName + " and sent to queue " + anotherQueueName + ".");
Console.WriteLine();
//
// TRANSACTION 3
// Transactionally receive messages from another queue and send them back to the original queue.
// At the last moment, ABORT.
//
Console.WriteLine("TRANSACTION #3");
IStompTransaction tr3 = await connection.BeginTransactionAsync();
// Creating a subscription from a transaction guarantees that acknowledgements will make part
// of the transaction.
IAsyncDisposable sub3 =
await tr3.SubscribeAsync(
new ProcessorObserver("#3", tr3), //All processing inside the observer is automatically made part of the transaction.
anotherQueueName,
StompAckValues.AckClientIndividualValue);
// Wait some time for the messages to be received and processed.
await Task.Delay(500);
// In transaction cases, subscription SHOULD be disposed before finishing the transaction.
// Otherwise, messages will keep being received and new (transacted) acknowledgements will
// be unknown for the message broker and may cause errors.
await sub3.DisposeAsync();
//Abort.
await tr3.AbortAsync();
Console.WriteLine("Nothing should have happened because this transaction was aborted.");
Console.WriteLine();
//
// TRANSACTION 4
// Transactionally receive messages from another queue and send them back to the original queue.
// At the last moment, COMMIT.
//
Console.WriteLine("TRANSACTION #4");
IStompTransaction tr4 = await connection.BeginTransactionAsync();
IAsyncDisposable sub4 = await tr4.SubscribeAsync(
new ProcessorObserver("#4", tr4), //All processing inside the observer is automatically made part of the transaction.
anotherQueueName,
StompAckValues.AckClientIndividualValue);
// Wait some time for the messages to be received and processed.
await Task.Delay(500);
// In transaction cases, subscription SHOULD be disposed before finishing the transaction.
// Otherwise, messages will keep being received and new (transacted) acknowledgements will
// be unknown for the message broker and may cause errors.
await sub4.DisposeAsync();
// Commit.
await tr4.CommitAsync();
Console.WriteLine("Messages processed from " + anotherQueueName + " and sent to queue " + aQueueName + ".");
Console.WriteLine();
//
// QUEUE DUMP
// Transactionally receive messages from another queue and send them back to the original queue.
// At the last moment, COMMIT.
//
Console.WriteLine("QUEUE " + aQueueName.ToUpper() + " DUMP");
Console.WriteLine("Show the messages in their final destination.");
Console.WriteLine();
IAsyncDisposable sub5 =
await connection.SubscribeAsync(
new ExampleObserver("QUEUE " + aQueueName + " DUMP"),
aQueueName,
StompAckValues.AckClientIndividualValue);
await Task.Delay(500);
await sub4.DisposeAsync();
// Disconnect.
await connection.DisconnectAsync();
}
}
public TransactionalObserver(IStompConnection connection, string name)
{
_connection = connection;
_name = name;
}
/// <summary>
/// This example shows the basic usage of the high level API of the library.
///
/// Four messages are going to be sent to a queue and they will be read from the same queue.
///
/// High level API features.
/// - High level interfaces to ease the flow of the application: IStompConnector,
/// IStompConnection, IStompMessage, IStompTransaction and IObserver<IStompMessage>.
/// - Built upon an observer pattern. It can be used for reactive application approaches.
/// - Message receipt confirmations and sequence number generation for frames are
/// automatically handled by the library.
/// - Thread-safety.
/// - You would rarely have to interact with STOMP frames directly.
///
/// </summary>
public static async Task ExampleConnector()
{
//A connection to the TCP server socket is created.
using (TcpClient tcpClient = new TcpClient(serverHostname, serverPort))
// IStompConnector is an IDisposable. A Stomp12Connector parametrized using the constructor.
// Stomp12Connector receives as parameters: a stream, the name of the virtual host,
// a username (optional) and a password (optional).
// Stomp12Connector may also receive a parameter 'retryTimeout' (TimeSpan, by default: 30 seconds)
// which is the time before a command is re-send if it does not receive a response.
using (IStompConnector stompConnector = new Stomp12Connector(tcpClient.GetStream(), virtualHost, login, passcode))
{
//Connect to the STOMP service.
IStompConnection connection = await stompConnector.ConnectAsync(heartbeat : new Heartbeat(30000, 30000));
// Send a couple of messages with string content.
for (int i = 1; i <= 2; i++)
{
await connection.SendAsync(
aQueueName, // Queue/Topic to send messages to.
messageContent + " #" + i, // The message content. String (by default UTF-8 encoding is used).
false, // Optional - Does a receipt confirmation is used in SEND command?. Default: false.
null, // Optional - Collection of key-value pairs to include as non-standard headers.
CancellationToken.None); // Optional - A CancellationToken.
}
// Subscribe to receive messages.
// Calling 'SubscribeAsync' returns an IDisposable which can be called to unsubscribe.
// It is not mandatory to dispose the subscription manually. It will be disposed when
// the stompConnector is disposed or if an exception in the stream occurs.
IDisposable subscription =
await connection.SubscribeAsync(
new ExampleObserver(), // An observer. A class implementing IObserver<IStompMessage>.
aQueueName, // Queue/Topic to observe from.
StompAckValues.AckAutoValue, // Optional - Ack mode: "auto", "client", "client-individual". Default: "auto".
false, // Optional - Does a receipt confirmation is used in SUBSCRIBE command?. Default: false.
null, // Optional - Collection of key-value pairs to include as non-standard headers.
CancellationToken.None); // Optional - A CancellationToken.
// Messages with byte content can also be send.
byte[] aByteMessageContent = new byte [] { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
// Send two more messages using SendAsync byte version.
for (int i = 0; i < 2; i++)
{
await connection.SendAsync(
aQueueName, // Queue/Topic to send messages to.
aByteMessageContent, // The message content.
MediaTypeNames.Application.Octet, // Message content type.
true, // Optional - Does a receipt confirmation is used in SEND command?. Default: false.
// In this case, a confirmation receipt will be awaited before the task is completed.
null, // Optional - Collection of key-value pairs to include as non-standard headers.
CancellationToken.None); // Optional - A CancellationToken.
}
// Wait some time for the messages to be received.
await Task.Delay(500);
// Unsubscribe.
subscription.Dispose();
// Disconnect.
await connection.DisconnectAsync();
}
}
/// <summary>
/// This is another example of the basic usage of the high level API of the library.
///
/// Multiple messages are going to be sent to a topic and a queue. After that,
/// multiple observers will receive the messages.
/// </summary>
/// <returns></returns>
public static async Task ExampleConnectorAnother()
{
using (TcpClient tcpClient = new TcpClient(serverHostname, serverPort))
using (IStompConnector stompConnector = new Stomp12Connector(tcpClient.GetStream(), virtualHost, login, passcode))
{
IStompConnection connection = await stompConnector.ConnectAsync();
//
// QUEUE CASE
//
Console.WriteLine("TWO OBSERVERS ON A QUEUE");
Console.WriteLine("------------------------");
Console.WriteLine();
// Subscribe two observers to one queue.
await connection.SubscribeAsync(new ExampleObserver("QUEUE OBSERVER 1"), aQueueName, StompAckValues.AckClientIndividualValue, true);
await connection.SubscribeAsync(new ExampleObserver("QUEUE OBSERVER 2"), aQueueName, StompAckValues.AckClientIndividualValue, true);
// Send three messages.
for (int i = 1; i <= 3; i++)
{
// As you see the receipt flag is true, so SendAsync will wait for a receipt confirmation.
await connection.SendAsync(aQueueName, messageContent + " #" + i, true);
}
// Wait some time for the messages to be received.
await Task.Delay(500);
//
// TOPIC CASE
//
Console.WriteLine("TWO OBSERVERS ON A TOPIC");
Console.WriteLine("------------------------");
Console.WriteLine();
// Subscribe two observers to one topic.
await connection.SubscribeAsync(new ExampleObserver("TOPIC OBSERVER 1"), aTopicName, StompAckValues.AckClientIndividualValue, true);
await connection.SubscribeAsync(new ExampleObserver("TOPIC OBSERVER 2"), aTopicName, StompAckValues.AckClientIndividualValue, true);
// Send three messages. As you see the receipt flag is true.
for (int i = 1; i <= 3; i++)
{
// As you see the receipt flag is true, so SendAsync will wait for a receipt confirmation.
await connection.SendAsync(aTopicName, messageContent + " #" + i, true);
}
// Wait some time for the messages to be received.
await Task.Delay(500);
// Disconnect.
await connection.DisconnectAsync();
}
// This delay is for console output formatting purposes.
// It makes sure the OnCompleted methods of the observers are invoked before
// showing the main menu again. In other words, when this is removed, completion
// messages of the observer may appear after the main menu has been showed.
await Task.Delay(500);
}
