code: @Override
    @Transactional(readOnly = true)
    @RunAsSystem
    public UserDetails findUserByToken(String token) {
      Token molgenisToken = getMolgenisToken(token);
      return userDetailsService.loadUserByUsername(molgenisToken.getUser().getUsername());
    }
docs: Find a user by a security token
  
  @param token security token
  @return the user or null if not found or token is expired