Throw exception during CreateConnectionAsync in case of wrong credentials

[lukebakken]

Discussed in #1776

^{Originally posted by plewam January 27, 2025}
Hello,

I create a new IConnection using below call.

Connection = await ConnectionFactory.CreateConnectionAsync(cancellationToken).ConfigureAwait(false);

Inside the ConnectionFactory I have to specify Hostname, Port, UserName and so. In case the host is not reachable the above call will give me a BrokerUnreachableException which is the desired behaviour. However in case the combination of UserName and Password is wrong, the above call will succeed. The IConnection object is also set and initialised. This causes my application to continue to subscribe to queues and so on. However shortly after the above call I will receive a ConnectionShutdown event which tells me that the credentials are wrong. From that moment on the IConnection object is also Null.

This behaviour causes a lot of NullReferenceExceptions throughout my application code. Ideally the CreateConnectionAsync call will throw an exception immediately telling me that the credentials are wrong. This way I can abort the further subscribing to queues immediately.

Kind regards,

Mathis