MassTransit交易发布

Question

I can't figure out how I can publish a message transactional using MassTransit 3.1.2 and RabbitMQ 3.6.0. I have a basic scenario where I save something to the database and then I want to publish an event. Wrapping a System.Transactions.TransactionScope around it does not work, before I complete the scope the message is already sent:

using (var scope = new TransactionScope(TransactionScopeOption.Required))
{
     // Save to database here.

     bus.Publish(new EntityCreatedEvent());

     // Event is already published at this point.

     scope.Complete();
}

The bus is created as follows:

var rabbitMqHostAddress = new Uri($"rabbitmq://{ConfigurationManager.AppSettings["RabbitMqHost"]}/");

var bus = Bus.Factory.CreateUsingRabbitMq(r =>
{
    r.Host(rabbitMqHostAddress, h =>
    {
        h.Username(ConfigurationManager.AppSettings["RabbitMqUsername"]);
        h.Password(ConfigurationManager.AppSettings["RabbitMqPassword"]);
    });
});

Answer 1

RabbitMQ does not enroll in transactions. This is not possible.

Answer 2

I know its been a while for this, and I might not have understood the question correctly but if you want to raise the event after the database transaction is done you can probably do something like this

using (var scope = new TransactionScope(TransactionScopeOption.Required))
{
 // Save to database here.

scope.TransactionCompleted += (sender, args) => { bus.Publish(new EntityCreatedEvent()); };

 // Event is already published at this point.

 scope.Complete();
}