The operations of the WSO2 Governance Registry can now be accessed through Web Service calls using the Web Service API (WS-API).
The WS-API supports almost all operations exposed through the main Registry API. A WS client is provided for the WS-API which allows you to access the Registry just as you would through the main Registry API.
See more information about the Web Services API in the article written by the Tharindu Mathew.
See WS-API Sample as an example.