apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/spi/springsecurity/SpringSecurityUserService.java/SpringSecurityUserService/searchUsers
class SpringSecurityUserService:  @Override
  public List<UserInfo> searchUsers(String keyword, int offset, int limit) {
    List<UserPO> users = this.findUsers(keyword);
    if (CollectionUtils.isEmpty(users)) {
      return Collections.emptyList();
    }
    return users.stream().map(UserPO::toUserInfo)
        .collect(Collectors.toList());
  }