Apply AutoDelete only for exchange but not queue

[s-horbach]

Hello,

Since MassTransit always creates both queue and exchange with the same name, i'm wondering if that's possible to set AutoDelete only for exchange?

The reason i need this is i have a quorum queue which cannot be auto-deleted, so i applied x-expires for it. But in order for exchange to be also deleted i need to set its AutoDelete=true.

Unfortunately, when i do so, i get an exception invalid property 'auto-delete' for queue because AutoDelete is applied for both queue and exchange, but quorum queue cannot be used together with AutoDelete=true.

Could you help me to find a proper solution, please?

services.AddMassTransit<ISecondBus>(busRegistrationConfig =>
{
    busRegistrationConfig.AddConsumer<MyConsumer>();

    busRegistrationConfig.UsingRabbitMq((context, rabbitBusFactoryConfig) =>
    {
        rabbitBusFactoryConfig.Host("<Connection string>");
        
        rabbitBusFactoryConfig.ReceiveEndpoint("My-endpoint", receiveEndpointConfig =>
        {
            receiveEndpointConfig.Durable = true;
            receiveEndpointConfig.SetQuorumQueue();
            receiveEndpointConfig.AutoDelete = true;
            receiveEndpointConfig.SetQueueArgument("x-expires", TimeSpan.FromSeconds(5));

            receiveEndpointConfig.Consumer<MyConsumer>(context);
        });
    });
});

Transport: RabbitMQ

[s-horbach]

i managed to solve the issue by replacing
receiveEndpointConfig.SetQueueArgument("x-expires", TimeSpan.FromSeconds(5));
with
receiveEndpointConfig.QueueExpiration = TimeSpan.FromSeconds(5);

both lines eventually do the same, that is add "x-expires" argument to the queue but afaik there is a subtle difference:

• when i set AutoDelete = true that applies it to both exchange and queue (of the same MT endpoint)
• then i set QueueExpiration, which basically discards AutoDelete for a queue but still keeps it for exchange

ℹ️ this is only my assumption based on the piece of code i found in MT:

var queueAutoDelete = settings.AutoDelete;
if (settings.QueueExpiration.HasValue)
{
    queueArguments["x-expires"] = (long)settings.QueueExpiration.Value.TotalMilliseconds;
    queueAutoDelete = false; // <-- discards auto deletion for a Queue if QueueExpiration was specified
}