Override Pageable findAll for selecting fewer columns in Spring Data Rest

Question

How to Override spring data repository to select only selected columns when going to pages that are discovered from /api page in spring data rest.

I added findAll as below -

public interface UserRepository extends BaseRepository<User, Integer>, UserRepositoryCustom {

    @Query("select u from User u where email = :email and password = :password")
    @Cacheable(value = "user-cache", key = "#user.login")
    @RestResource(exported = false)
    public User findUserByEmailAndPassword(@Param("email") String email, @Param("password") String password);

    @RestResource(rel = "byEmail", path = "byEmail")
    public User findUserByEmail(@Param("email") String email);

    @RestResource(rel = "byPhone", path = "byPhone")
    public User findUserByPhone(@Param("phone") String phone);

     @Override 
     @Query("select u.id,u.email,u.phone from User u ")
     public Page<User> findAll(Pageable pageable);
}

/api/users is giving an error -

{"cause":null,"message":"PersistentEntity must not be null!"}

Answer 1

I created a UserSummaryProjection class in same package as User

@Projection(name = "summary", types = User.class)
public interface UserSummaryProjection {

    Integer getId();

    String getEmail();

}

Then, going at /api/users or /users/3?projection=summary gives me desired result without changing the Repository.

Answer 2

Selecting subelements of User and still creating a User is somewhat counterintuitive.

I would create another entity for example UserDetails , that will be mapped by the same table with the same mapping.

public class UserDetails {
    private int uid;
    private String email;
    private String phone;
}

And create a Repository, based on this new Entity.