Connect endpoint and then connect consumer after some time in MassTransit

Question

How to connect an endpoint(exchange-exchange-queue) in masstransit, accumulate data in the queue, and then, after some time, connect a consumer to this endpoint?

I wanted to do something like:

Task.Run(async () =>
{
    for (var i = 0;; i++)
    {
        await _bus.Publish(new Event(i), stoppingToken);
        await Task.Delay(1_000, stoppingToken);
    }
});

// a command comes to connect the consumer

var endpoint = _bus.ConnectReceiveEndpoint();
await endpoint.Ready;

// I prepare the consumer, as soon as it is ready, I connect it, 
    then I read the data that has accumulated during the preparation 
    (my consumer needs to load the state before reading the data, 
    and also cannot skip the data during its preparation)

endpoint.ReceiveEndpoint.ConnectConsumer(() =>
    _serviceProvider.GetRequiredService<EventConsumer>());

but this code will not create an exchange-exchange relationship, so the queue will be empty

Answer 1

If the exchange bindings (wired to the receive endpoint, which ultimately is a queue) do not exist when messages are published, they are discarded by RabbitMQ.

You would need to connect the receive endpoint in advance, so that the messages end up in the queue.