//------------------------------------------BROKER RECONNECTION------------------------------------------//
// Called when a channel is notified of an connection issue. Once the connection is
// reestablished, the centrally saved exchanges and queues need to be recreated on the
// new connection. This is important when using a broker fail-over behind a load-balancer
// since the backup broker my not have the exchanges.
private void RestablishConnection(MessageConsumer messageConsumer, ShutdownEventArgs shutdownEvent)
{
if (_connMgr.IsBrokerConnected(messageConsumer.BrokerName))
{
return;
}
if (_connMgr.IsUnexpectedShutdown(shutdownEvent))
{
_logger.LogError(RabbitMqLogEvents.BROKER_CONFIGURATION, "Connection to broker was shutdown. Reconnection will be attempted.");
string brokerName = messageConsumer.BrokerName;
IEnumerable <BrokerMeta> brokerMeta = _exchangeRep.LoadAsync(brokerName).Result;
_connMgr.ReconnectToBroker(brokerName);
// Restore the exchanges and queues on what might be a new broker.
using (IModel channel = _connMgr.CreateChannel(brokerName))
{
ReCreatePublisherExchanges(channel, brokerMeta);
ReCreateConsumerQueues(channel, brokerMeta);
_exchangeConsumer.BindConsumersToQueues(_messageConsumers, messageConsumer.BrokerName);
_rpcExchangeConsumer.BindConsumersToRpcQueues();
}
// Watch for future issues.
AttachBokerMonitoringHandlers();
_logger.LogDebug(RabbitMqLogEvents.BROKER_CONFIGURATION, "Connection to broker was reestablished.");
}
}
public static EventingBasicConsumer GetBasicConsumer(this IModel channel,
MessageConsumer eventConsumer)
{
Check.NotNull(channel, nameof(channel));
Check.NotNull(eventConsumer, nameof(eventConsumer));
var basicConsumer = new EventingBasicConsumer(channel);
channel.BasicConsume(eventConsumer.QueueName, eventConsumer.QueueSettings, basicConsumer);
return(basicConsumer);
}
public static void QueueDeclare(this IModel channel,
MessageConsumer eventConsumer)
{
Check.NotNull(channel, nameof(channel));
Check.NotNull(eventConsumer, nameof(eventConsumer));
if (eventConsumer.IsBrokerAssignedName)
{
eventConsumer.QueueName = channel.QueueDeclare().QueueName;
return;
}
channel.QueueDeclare(eventConsumer.QueueName,
eventConsumer.QueueSettings.IsDurable,
eventConsumer.QueueSettings.IsExclusive,
eventConsumer.QueueSettings.IsAutoDelete, null);
}
public static void QueueBind(this IModel channel, MessageConsumer eventConsumer)
{
Check.NotNull(channel, nameof(channel));
Check.NotNull(eventConsumer, nameof(eventConsumer));
if (eventConsumer.RouteKeys.Empty())
{
channel.QueueBind(eventConsumer.QueueName, eventConsumer.ExchangeName, "");
return;
}
foreach (string routeKey in eventConsumer.RouteKeys)
{
if (routeKey.IsNullOrWhiteSpace())
{
throw new InvalidOperationException(
$"The queue named: {eventConsumer.QueueName} on the exchange named: {eventConsumer.ExchangeName} " +
$"has a null route-key value specified.");
}
channel.QueueBind(eventConsumer.QueueName, eventConsumer.ExchangeName, routeKey.ToUpper());
}
}
