List available Enterprise Project Types using Project Server Interface

Question

I want to query a Project Server 2010 installation for a list of available Enterprise Project Types (their names and GUIDs) using a webservice (PSI).

I can't find out how to do this anywhere. I found a way using the client-side object model but cannot find any examples using web services. Has anyone ever done this?

I found one answer here but it deals only with custom fields.

(The goal is to create/update a project using a Enterprise Project Type & its attached template.)

Answer 1

I found 2 available methods inside of Workflow Service:

1. Workflow.ReadAvailableEnterpriseProjectTypes - list of EPTs available for the current user
2. Workflow.ReadEnterpriseProjectTypeList Method - list of all known EPTs.

The only possible problem I see is a set of required permissions:

1. Manage Workflow
2. Change Workflow
3. + NewProject for the 1st method.