I've been looking around and I've found that there's a REST API request that can get all security groups and identities:
tfs/DefaultCollection/TestProject/_api/_identity/ReadIdentitiesPageJson?__v=5
But I can't figure out the relationship between 'user' and 'group', because I require that to get all the members in a group using a custom control in Web Access.
My question is how can I get all members in a special group? Is there a REST API can rech this goal?