I am using VSTS Pullrequest create API method to automate the PR creation, in the request i need to provide various IdentityRef id values for createdby/autocompleteby/reviewers properties. In my case all i have is user details (like full name, email address - user1@domain.com ), in this case how do i retrieve the IdentityRef Guid so that i can pass it to PR Create API.
Any help is appreciated.