Hello, OVirt community!

I have some problems in understanding with OVirt (v 3.6.0) API.
I'm trying to create user with specifying his roles, by using such signature in POST call:

<user>
    <user_name>testuser@saml-auth</user_name>
    <roles>
        <role id="some_role_id1"/>
        <role id="some_role_id2"/>
        <role id="some_role_id3"/>
    </roles>
</user>

The user is created but without the roles.
The next issues, that I encountered is associated with updating of existing user (adding the roles to him). I am trying to do PUT call on .../ovirt-engine/api/users/long_user_id/roles :

<role id="some_role_id1"/>

But this doesn't work.
Please, give we insight in what I am doing wrong.


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Sincerely,
Konstantin Klymuk.