Access $user.attr in a CDS projection

[T1mey]

Hello CAP experts,

I have a list of attributes coming from our IDP. Now I wanna like limit the list of overall "LDAPGroups" to the one's the user has.

@readonly

    entity LDAPGroups as

        projection on app.LDAPGroups

        where ldapDn IN ($user.LDAPGroups);

The thing is  that the compiler complains:

Error: No value found for variable “$user.LDAPGroups”. Use option ‘variableReplacements’ to specify a value for “$user.LDAPGroups”

I tried to use the 

session_context('$user.LDAPGroups')

in various combinations... but no luck with it. Anybody an idea how I can solve this?

[T1mey · Accepted solution]

Found it by myself... This does the trick.

 @restrict: [

        {

            grant: [ 'READ' ],

            where: 'ldapDn IN ($user.LDAP_Groups)'

        }

    ]

    @readonly

    entity LDAPGroups as

        projection on app.LDAPGroups;