Hi Jori.
I don't see a straight forward way to resolve your issue.
The classes defined inherently implement this behavior of exposing the URL. So, if you have the connection object, URL will be visible. However, custom classes can be created to replicate the same working but to hide the URL. This approach can lead to complications, but it seems like the only way to return a connection object and still not expose the URL. The following link will help you understand classes in MATLAB:
I would suggest a different implementation where you don't return the connection object to the user. Instead, the funcion can directly perform any operation that they want using that connection object and just return what is necessary for the user. This way, the connection URL will never be exposed.
I also don't understand the significance of using a key. If the above-mentioned approaches don't help you, could you please help me understand why a key is required along with the username and password so that I can look at this again and see if there is a better approach?
