So, in the openstack-common Chef cookbook library, we have an endpoint library function that can be used for this (and subsequently you should be able to remove the above related attributes). Look in recipes/server.rb for calls to:

```ruby
identity_admin_endpoint = endpoint "identity-admin"
identity_endpoint = endpoint "identity-api"
```

You can inject the above variables into the template and call identity_endpoint.to_s instead of referencing a node attribute