5.从零搭建WebApi接口开发框架-设计Controller

这里面主要设计以下接口:

  • 用户登录获取accessToken
  • news的增删改查接口

为了保存accessToken,需要引入redis,为了定义返回的json,需要定义公共的JsonResult,下面依次说明

pom.xml添加依赖

<dependency>
     <groupId>org.springframework.boot</groupId>
     <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>

application.yml增加redis的配置信息

#config Redis
spring:
  redis:
    host: 127.0.0.1
    port: 6379
    database: 0
    password:

定义redis调用相关类

共包括RedisUtil工具类、RedisKey公共值

@Component
public class RedisUtil {
    /**
     * 注入的stringRedisTemplate
     */
    @Autowired
    private StringRedisTemplate stringRedisTemplate;
    /**
     * redisTemplate
     */
    @Autowired
    private RedisTemplate<?, ?> redisTemplate;

    /**
     * 设置key和对象的value
     *
     * @param key key
     * @param value value
     */
    public void set(final String key, Object value) {
        final byte[] vbytes = SerializeUtil.serialize(value);
        redisTemplate.execute(new RedisCallback<Object>() {
            @Override
            public Object doInRedis(RedisConnection connection) throws DataAccessException {
                connection.set(redisTemplate.getStringSerializer().serialize(key), vbytes);
                return null;
            }
        });
    }

    /**
     * 设置key和value,并加上时间(秒)
     *
     * @param key key
     * @param value value
     * @param l 时间
     */
    public void set(final String key, Object value, final long l) {
        final byte[] vbytes = SerializeUtil.serialize(value);
        redisTemplate.execute(new RedisCallback<Object>() {
            @Override
            public Object doInRedis(RedisConnection connection) throws DataAccessException {
                connection.setEx(redisTemplate.getStringSerializer().serialize(key), l, vbytes);
                return null;
            }
        });
    }

    /**
     * 根据key来取值
     *
     * @param key key
     * @param elementType 数据类型
     * @param <T> 泛型
     * @return 获取的对象
     */
    public <T> T get(final String key, Class<T> elementType) {
        return redisTemplate.execute(new RedisCallback<T>() {
            @Override
            public T doInRedis(RedisConnection connection) throws DataAccessException {
                byte[] keybytes = redisTemplate.getStringSerializer().serialize(key);
                if (connection.exists(keybytes)) {
                    byte[] valuebytes = connection.get(keybytes);
                    T value = (T) SerializeUtil.deserialize(valuebytes);
                    return value;
                }
                return null;
            }
        });
    }

    /**
     * 根据key删除该值
     *
     * @param key key
     */
    public void del(final String key) {
        final byte[] keyBytes = redisTemplate.getStringSerializer().serialize(key);
        redisTemplate.execute(new RedisCallback<Object>() {
            @Override
            public Object doInRedis(RedisConnection connection) throws DataAccessException {
                connection.del(keyBytes);
                return null;
            }
        });
    }
}
public class RedisKey {
    //用户登录后的accesstoken
    public static final String ACCESS_TOKEN = "com:balance:accesstoken";
}

定义公共返回的json对象

public class JsonResult {
    /**
     * 是否成功
     */
    private boolean success;
    /**
     * 消息
     */
    private String message;
    /**
     * 返回码
     */
    private String code;

    /**
     * 额外的数据
     */
    private Object data;

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public boolean isSuccess() {
        return success;
    }

    public void setSuccess(boolean success) {
        this.success = success;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public Object getData() {
        return data;
    }

    public void setData(Object data) {
        this.data = data;
    }

    public JsonResult(boolean success, String code, Object data) {
        this(success, code);
        this.data = data;
        this.message = ReturnCodeUtil.getMsg(code);
    }

    public JsonResult() {
    }

    public JsonResult(boolean success) {
        this.success = success;
    }

    /**
     * message通过code获取
     *
     * @param success
     * @param code
     */
    public JsonResult(boolean success, String code) {
        this(success);
        this.code = code;
        this.message = ReturnCodeUtil.getMsg(code);
    }

    /**
     * 三个参数,message自己赋值,不通过code获取
     *
     * @param success
     * @param code
     * @param message
     */
    public JsonResult(boolean success, String code, String message) {
        this(success);
        this.code = code;
        this.message = message;
    }

}

这个类用的地方非常多,基本每个controller都会用到,一定要通用、易使用,为了定义公共返回码,还需要定义一个类存储公共的全局返回码,GlobalReturnCode

public class GlobalReturnCode {
    /**
     * 保存成功
     */
    public static final String SAVE_SUCCESS = "10001";
    /**
     * 删除成功
     */
    public static final String DELETE_SUCCESS = "10002";
    /**
     * 操作成功
     */
    public static final String OPERA_SUCCESS = "10003";
    /**
     * 审核成功
     */
    public static final String AUDIT_SUCCESS = "10004";

    /**
     * 操作失败
     */
    public static final String OPERA_FAILURE = "20001";

    /**
     * 无权限
     */
    public static final String NO_AUTH = "30001";
    /**
     * 系统错误
     */
    public static final String SYSTEM_ERROR = "30002";
    /**
     * 参数错误
     */
    public static final String PARAM_ERROR = "30003";

    /**
     * 路径不存在
     */
    public static final String SYSTEM_PATH_NOEXIST = "30004";
}
public class ReturnCodeUtil {
    //定义返回码及文字数据
    private static Map<String, String> returnCodeMap;

    static {
        returnCodeMap.put(GlobalReturnCode.SAVE_SUCCESS, "保存成功");
        returnCodeMap.put(GlobalReturnCode.DELETE_SUCCESS, "删除成功");
        returnCodeMap.put(GlobalReturnCode.OPERA_SUCCESS, "操作成功");
        returnCodeMap.put(GlobalReturnCode.AUDIT_SUCCESS, "审核成功");

        
        returnCodeMap.put(GlobalReturnCode.OPERA_FAILURE, "操作失败");
        returnCodeMap.put("20102", "账号或密码错误");


        returnCodeMap.put(GlobalReturnCode.NO_AUTH, "无权限");
        returnCodeMap.put(GlobalReturnCode.SYSTEM_ERROR, "系统错误");
        returnCodeMap.put(GlobalReturnCode.PARAM_ERROR, "参数错误");
        returnCodeMap.put(GlobalReturnCode.SYSTEM_PATH_NOEXIST, "路径不存在");

    }


    /**
     * 获取返回的中文说明
     *
     * @param resultCode 返回码
     * @return 中文名称
     */
    public static String getMsg(String resultCode) {
        if (returnCodeMap.containsKey(resultCode)) {
            return returnCodeMap.get(resultCode);
        } else {
            return "";
        }
    }
}

ReturnCodeUtil这个类定义类根据返回码获取对应的中文名的方法,实际应用中,可以把固定的返回码存储到数据库中或者配置文件中。

LoginController

@RestController
@RequestMapping("/")
public class LoginControler {
    @Autowired
    private UserService userService;
    @Autowired
    private RedisUtil redisUtil;

    /**
     * 用户登录
     */
    @PostMapping("/checkLogin")
    public JsonResult checkLogin(HttpServletRequest request, @RequestBody LoginDto loginDto) {
        User user = userService.getByUsername(loginDto.getUsername());
        if (user != null && user.getPasssword().equals(loginDto.getPassword())) {
            //登录成功
            String accessToken = UUID.randomUUID().toString();
            //放入redis
            redisUtil.set(RedisKey.ACCESS_TOKEN + accessToken, user, 30 * 60);
            Map<String, String> map = new HashMap<>();
            map.put("accessToken", accessToken);
            JsonResult jsonResult = new JsonResult(true, GlobalReturnCode.OPERA_SUCCESS, accessToken);
            return jsonResult;
        } else {
            JsonResult jsonResult = new JsonResult(false, "20102");
            return jsonResult;
        }
    }
}

这里面是登录后获取accessToken的代码,统一返回JsonResult。
要说明一点,可以利用@PostMapping来指定该请求只接收post,简化了以前的RequestMapping设置。用户账号或密码错误,返回

用户登录成功,返回accessToken


登录成功.png

账号或密码错误.png

NewsController

@RestController
@RequestMapping("/news")
public class NewsController {
    @Autowired
    private NewsService newsService;

    @PostMapping("/add")
    public JsonResult add(HttpServletRequest request, @RequestBody News news) {
        int flag = newsService.add(news);
        if (flag == 1) {
            return new JsonResult(true, GlobalReturnCode.SAVE_SUCCESS);
        } else {
            return new JsonResult(false, GlobalReturnCode.OPERA_FAILURE);
        }
    }

    @PostMapping("/update")
    public JsonResult update(HttpServletRequest request, @RequestBody News news) {
        int flag = newsService.update(news);
        if (flag == 1) {
            return new JsonResult(true, GlobalReturnCode.SAVE_SUCCESS);
        } else {
            return new JsonResult(false, GlobalReturnCode.OPERA_FAILURE);
        }
    }

    @PostMapping("/delete")
    public JsonResult delete(HttpServletRequest request, @RequestBody Map<String, String> map) {
        int flag = newsService.delete(Integer.parseInt(map.get("id")));
        if (flag == 1) {
            return new JsonResult(true, GlobalReturnCode.SAVE_SUCCESS);
        } else {
            return new JsonResult(false, GlobalReturnCode.OPERA_FAILURE);
        }
    }

    @PostMapping("/list")
    public JsonResult list(HttpServletRequest request) {
        List<News> list = newsService.list();
        return new JsonResult(true, GlobalReturnCode.OPERA_SUCCESS, list);
    }

    @PostMapping("/get")
    public JsonResult get(HttpServletRequest request, @RequestBody Map<String, String> map) {
        News news = newsService.get(Integer.parseInt(map.get("id")));
        return new JsonResult(true, GlobalReturnCode.OPERA_SUCCESS, news);
    }
}
新增news.png
根据id获取news.png

这里面比较简单,需要注意的一点就是,传参数即使只包括一个字段,也需要用@RequestBody来接收

整个controller就开发完了,是不是相当简单,后续的就是对接口调用做一些全局控制了。

源码下载

本例子详细源码

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