Fetch ClaimType Enumerations via REST

问题

We're happily enriching our claims via custom RESTful API, but is it possible to instead display the fetched claim values (comma delimetered, for example) in a drop-down and ask used to pick one?

<ClaimType Id="city">
  <DisplayName>city where you work</DisplayName>
  <DataType>string</DataType>
  <UserInputType>DropdownSingleSelect</UserInputType>
  <Restriction>
      <!-- FETCH THESE VIA REST --> 
      <Enumeration Text="Bellevue" Value="bellevue" SelectByDefault="false" />
  </Restriction>
</ClaimType>

来源：https://stackoverflow.com/questions/49253190/fetch-claimtype-enumerations-via-rest