how to dynamically grab the folder list from vCenter infra provider for use in a service dialog?

[mschmitt-nasuni]

I'm trying to create a service dialog, and as part of the dialog, I would like the user to be able to place the VM inside a folder that exists on the infrastructure provider.

I have a dropdown element named 'placement_folder_name' which, I'm assuming, is how I set the folder the VM should be placed in. I've set the field to Dynamic, and from my reading, the Entrypoint should be Infrastructure/VM/Provisioning/StateMachines/Methods/PreProvision.

But after that, I get stuck. I'm not sure what to do next to get it to pull the folder list and populate a dropdown list with the values.

Any help would be appreciated!