基于FeignClient提供简单的用户查询服务

前言：

　　由于系统升级，之前的员工数据库（mongo库）被弃用，改为用python维护的mysql库，其他系统访问通过http请求，表结构对外不可见，其他系统之前对员工mongo库的依赖要解除。每套系统都去写请求的接口太麻烦，所以打算写一个员工查询服务，http请求用原生的FeignClient实现。

实现思路：

　　场景：python端只提供了查询所有员工，其他系统请求多种多样。

　　解决：请求接口 -->  查询所有员工  -->  FeignClient包装的http请求  -->  过滤条件

实现步骤演示：

• Feign包装的http请求：

/**
 * 对外暴露接口.
 */
@FeignClient(name = XXXXClientConfig.APPLICATION_NAME, url = "https://xx.xxxx.com")
public interface IEmployService {

    @RequestMapping(value = "/xx/employee/search",
            headers = {"Content-Type=application/json",
            "App-Id=xxx",
            "App-Secret=xxxx"})
    @ResponseBody
    ReturnUser getAllUser(@RequestBody GetAllUserForm getAllUserForm);

}

• 员工服务接口：

@FeignClient(XXXXConfig.APPLICATION_NAME)
public interface IUserService {

    @RequestMapping(value = "/xxxx/getAll", method = RequestMethod.GET)
    List<User> getAll();

    @RequestMapping(value = "/xxxx/getUserByIds", method = RequestMethod.POST)
    List<User> getUserByIds(@RequestBody List<String> userIds);

    @RequestMapping(value = "/xxxx/getById", method = RequestMethod.GET)
    User getById(@RequestParam(value = "userId") String userId);

    @RequestMapping(value = "/xxxx/getByQuery", method = RequestMethod.POST)
    List<User> getByQuery(@RequestBody UserQuery userQuery);
}

• 员工服务实现：

@RestController
public class UserSearchService implements IUserService {
    private final static Logger log = LoggerFactory.getLogger("xxx");
    private List<User> users = null;
    private Long lastTime = null;
    @Resource
    private IEmployService employService;

    @Override
    public List<User> getAll() {
        if(users != null && users.size() > 0 && lastTime != null && (System.currentTimeMillis() - lastTime) <= 1000*60*10){
            return users;
        }
        try {
            GetAllUserForm form = new GetAllUserForm();
            form.setPageNo(1);
            form.setPageSize(99999);
            ReturnUser allUser = employService.getAllUser(form);
            users = new ArrayList<>();
            allUser.getData().getRecords().forEach(returnUser -> {
                User user = getUserFromReturnUser(returnUser);
                users.add(user);
            });
            lastTime = System.currentTimeMillis();
            return users;
        }catch (Exception e){
            if(users.size() > 0){
                return users;
            }else {
                throw new RuntimeException("getAll(): user is null");
            }
        }
    }

    @Override
    public List<User> getUserByIds(@RequestBody List<String> userIds) {
        List<User> all = getAll();
        List<User> users = all.stream().filter(user -> userIds.contains(user.getId())).collect(Collectors.toList());
        return users;
    }

    @Override
    public User getById(@RequestParam(value = "userId") String userId) {
        List<User> all = getAll();
        List<User> users = all.stream().filter(user -> user.getId().equals(userId))
                .collect(Collectors.toList());
        return users.size() == 1? users.get(0):null;
    }

    @Override
    public List<User> getByQuery(@RequestBody UserQuery userQuery) {
        List<User> list = new ArrayList<>();
        getAll().stream().filter(user -> {
            if (CommonUtil.isNotBlank(userQuery.getName())) {
                if (!userQuery.getName().equals(user.getName()) &&
                        !userQuery.getName().equals(user.getRealName())) {
                    return false;
                }
            }
            if (CommonUtil.isNotBlank(userQuery.getKeyword())) {
                if (!user.getName().contains(userQuery.getKeyword()) &&
                        !user.getRealName().contains(userQuery.getKeyword())) {
                    return false;
                }
            }
            if (userQuery.getIds() != null) {
                if (!userQuery.getIds().contains(String.valueOf(user.getNumber()))) {
                    return false;
                }
            }
            return true;
        }).forEach(user -> {
            list.add(user);
        });
        return list;
    }


    private User getUserFromReturnUser(Employee returnUser) {
        User user = new User();
        user.setName(returnUser.getName());
        return user;
    }

}

•  springboot启动添加

   @EnableFeignClients(basePackages = {XXXXClientConfig.PACKAGE_PATH})