SDR: Exclude fields from json for associated object - spring-data-rest

Question

I have an entities like this:
Restaurant
String name
User manager
User
String name
Date lastLogin
When I do GET /restaurants I want to inline the manager, but only with name, not with lastLogin.
When I do GET /users I want to see the full user: name + lastLogin
So I created a Restaurant-Projection and applied it as excerpt to the RestaurantRepo. But this embeds the full user into the restaurant.
When I create an excerpt project for user too, which omits the lastLogin field then it works for restaurants as expected but not for users because here the lastLogin is missing.
How can I solve this problem?
Thank you

Answer 1

You can do something like this (example from the spring data rest documentation)
#Projection(name = "virtual", types = { Person.class })
public interface VirtualProjection {
#Value("#{target.firstName} #{target.lastName}")
String getFullName();
}
So in your case this would result into this projection:
#Projection(name = "restaurantWithManagerName", types = { Restaurant.class })
public interface RestaurantWithManagerNameProjection {
String getName();
#Value("#{target.manager.name}")
String getManagerName();
}
If you want to keep the orginal structure with a nested User object you could achieve this by creating a custom reduced interface for the user and use it in your projection:
public interface UserLight {
String getName();
}
#Projection(name = "restaurantWithReducedManager", types = Restaurant.class)
public interface RestaurantWithManagerNameProjection {
String getName();
UserLight getManager();
}