private IBasicProperties GetRequestProperties(ICommand command, RpcProperties rpcProps)
{
IBasicProperties props = this.Channel.CreateBasicProperties();
props.Headers = new Dictionary <string, object> {
{ RPC_BROKER_NAME, _brokerName }
};
props.ReplyTo = ReplyQueueName;
props.CorrelationId = command.GetCorrelationId();
props.ContentType = rpcProps.ContentType;
props.Type = rpcProps.ExternalTypeName;
return(props);
}
public async Task <byte[]> Invoke(ICommand command, RpcProperties rpcProps,
CancellationToken cancellationToken,
byte[] messageBody)
{
Check.NotNull(command, nameof(command));
Check.NotNull(rpcProps, nameof(rpcProps));
Check.NotNull(messageBody, nameof(messageBody));
// Associate a correlation value with the outgoing message.
string correlationId = Guid.NewGuid().ToString();
command.SetCorrelationId(correlationId);
// Create a task that can be resolved in the future when the result
// is received from the reply queue.
var futureResult = new TaskCompletionSource <byte[]>();
var rpcPendingRequest = new RpcPendingRequest(futureResult, cancellationToken,
_consumerSettings.CancelRequestAfterMs);
_pendingRpcRequests[correlationId] = rpcPendingRequest;
IBasicProperties basicProps = GetRequestProperties(command, rpcProps);
Channel.BasicPublish(DEFAULT_EXCHANGE, _consumerSettings.RequestQueueName,
basicProps,
messageBody);
try
{
return(await futureResult.Task);
}
catch (TaskCanceledException ex)
{
// If the pending request task has been canceled, remove the pending
// request and unregister the cancellation delegate.
if (_pendingRpcRequests.TryRemove(correlationId, out RpcPendingRequest pendingRequest))
{
pendingRequest.UnRegister();
}
throw new BrokerException(
$"The RPC request with the correlation value of: {correlationId} was canceled. " +
$"The current timeout value is: {_consumerSettings.CancelRequestAfterMs} ms.",
ex);
}
}