add-admin-controller.java

@RestController
@RequestMapping("/admin")
@RequiredArgsConstructor
public class AdminController {

    private final UserManagementService userManagementService;

    @Secured("ROLE_ANONYMOUS")
    @PostMapping(path = "/user-claims/{uid}")
    public void setUserClaims(
            @PathVariable String uid,
            @RequestBody List<Permission> requestedClaims
    ) throws FirebaseAuthException {
        userManagementService.setUserClaims(uid, requestedClaims);
    }

}