eShopOnContainers/src/BuildingBlocks/EventBus/EventBusRabbitMQ/DefaultRabbitMQPersistentConnection.cs

118 lines
3.7 KiB
C#

namespace Microsoft.eShopOnContainers.BuildingBlocks.EventBusRabbitMQ;
public class DefaultRabbitMQPersistentConnection
: IRabbitMQPersistentConnection
{
private readonly IConnectionFactory _connectionFactory;
private readonly ILogger<DefaultRabbitMQPersistentConnection> _logger;
private readonly int _retryCount;
private IConnection _connection;
public bool Disposed;
readonly object _syncRoot = new();
public DefaultRabbitMQPersistentConnection(IConnectionFactory connectionFactory, ILogger<DefaultRabbitMQPersistentConnection> logger, int retryCount = 5)
{
_connectionFactory = connectionFactory ?? throw new ArgumentNullException(nameof(connectionFactory));
_logger = logger ?? throw new ArgumentNullException(nameof(logger));
_retryCount = retryCount;
}
public bool IsConnected => _connection is { IsOpen: true } && !Disposed;
public IModel CreateModel()
{
if (!IsConnected)
{
throw new InvalidOperationException("No RabbitMQ connections are available to perform this action");
}
return _connection.CreateModel();
}
public void Dispose()
{
if (Disposed) return;
Disposed = true;
try
{
_connection.ConnectionShutdown -= OnConnectionShutdown;
_connection.CallbackException -= OnCallbackException;
_connection.ConnectionBlocked -= OnConnectionBlocked;
_connection.Dispose();
}
catch (IOException ex)
{
_logger.LogCritical(ex.ToString());
}
}
public bool TryConnect()
{
_logger.LogInformation("RabbitMQ Client is trying to connect");
lock (_syncRoot)
{
var policy = RetryPolicy.Handle<SocketException>()
.Or<BrokerUnreachableException>()
.WaitAndRetry(_retryCount, retryAttempt => TimeSpan.FromSeconds(Math.Pow(2, retryAttempt)), (ex, time) =>
{
_logger.LogWarning(ex, "RabbitMQ Client could not connect after {TimeOut}s ({ExceptionMessage})", $"{time.TotalSeconds:n1}", ex.Message);
}
);
policy.Execute(() =>
{
_connection = _connectionFactory
.CreateConnection();
});
if (IsConnected)
{
_connection.ConnectionShutdown += OnConnectionShutdown;
_connection.CallbackException += OnCallbackException;
_connection.ConnectionBlocked += OnConnectionBlocked;
_logger.LogInformation("RabbitMQ Client acquired a persistent connection to '{HostName}' and is subscribed to failure events", _connection.Endpoint.HostName);
return true;
}
else
{
_logger.LogCritical("FATAL ERROR: RabbitMQ connections could not be created and opened");
return false;
}
}
}
private void OnConnectionBlocked(object sender, ConnectionBlockedEventArgs e)
{
if (Disposed) return;
_logger.LogWarning("A RabbitMQ connection is shutdown. Trying to re-connect...");
TryConnect();
}
void OnCallbackException(object sender, CallbackExceptionEventArgs e)
{
if (Disposed) return;
_logger.LogWarning("A RabbitMQ connection throw exception. Trying to re-connect...");
TryConnect();
}
void OnConnectionShutdown(object sender, ShutdownEventArgs reason)
{
if (Disposed) return;
_logger.LogWarning("A RabbitMQ connection is on shutdown. Trying to re-connect...");
TryConnect();
}
}