=============
后端_登录退出
=============

1 添加账户实体类

/src/main/java/com/weihome/barblog/entity/Account.java：

/**
 * 账户实体类
 */
@Data
public class Account implements Serializable {
    @NotBlank(message = "昵称不能为空")
    private String username;

    @NotBlank(message = "密码不能为空")
    private String password;
}

2 添加账户控制器类

/**
 * 账户控制器类
 */
@RestController
public class AccountController {
    @Autowired
    UserService userService;

    @Autowired
    JwtUtils jwtUtils;

    /**
     * 登录
     */
    @PostMapping("/login")
    public Result login(
        @Validated @RequestBody Account account,
        HttpServletResponse response) {

        // 根据用户名从数据库中读取用户信息
        User user = userService.getOne(
            new QueryWrapper<User>().eq("username",
                account.getUsername()));
        Assert.notNull(user, "用户不存在");

        // 验证密码(MD5摘要)
        if(!user.getPassword().equals(
            SecureUtil.md5(account.getPassword())))
            return Result.error("密码不正确");

        // 根据用户ID生成令牌并加入到响应头中
        String token = jwtUtils.generateToken(user.getId());
        response.setHeader("Authorization", token);
        response.setHeader("Access-control-Expose-Headers",
            "Authorization");

        // 响应成功
        return Result.ok(MapUtil.builder()
            .put("id", user.getId())
            .put("username", user.getUsername())
            .put("avatar", user.getAvatar())
            .put("email", user.getEmail())
            .map());
    }

    /**
     * 退出
     */
    @RequiresAuthentication
    @GetMapping("/logout")
    public Result logout() {
        SecurityUtils.getSubject().logout();
        return Result.ok(null);
    }
}

3 添加针对Assert断言的无效参数异常处理

/src/main/java/com/weihome/barblog/common/GlobalExcepitonHandler.java：

...
public class GlobalExcepitonHandler {
    ...
    /**
     * 无效参数异常
     */
    @ResponseStatus(HttpStatus.BAD_REQUEST) // 400
    @ExceptionHandler(value = IllegalArgumentException.class)
    public Result handler(IllegalArgumentException e) {
        log.error("无效参数异常", e);
        return Result.error(e.getMessage());
    }
    ...
}

4 运行测试

执行BarblogApplication.main()...

Postman:
    POST
        localhost:8081/login
    Body
        raw/JSON
{
    "username": "kitty",
    "password": "123456"
}
----------------------------
{
    "code": 400,
    "message": "用户不存在",
    "data": null
}

Postman:
    POST
        localhost:8081/login
    Body
        raw/JSON
{
    "username": "bear",
    "password": "123456"
}
----------------------------
{
    "code": 400,
    "message": "密码不正确",
    "data": null
}

Postman:
    POST
        localhost:8081/login
    Body
        raw/JSON
{
    "username": "bear",
    "password": "111111"
}
----------------------------
{
    "code": 200,
    "message": "操作成功",
    "data": {
        "id": 1,
        "avatar": "bear.png",
        "email": "johnmin74@hotmail.com",
        "username": "bear"
    }
}
Headers
    ...
    Authorization: eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzUxMiJ9.eyJzdWIiOiIxIiwiaWF0IjoxNjQ4MDkwMzEzLCJleHAiOjE2NDg2OTUxMTN9.mKL47JVwZlajifw9p8y9hD-X_60ib-t_zARHGsG8CGGD_wBCJCIrLhqO8ldYhWxeI_WNkdJGvCyvSC6z3Mdv8w
    ...            ^
                   |
               令牌字符串

Postman:
    GET
        localhost:8081/user/index
    Headers
        Authorization: eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzUxMiJ9.eyJzdWIiOiIxIiwiaWF0IjoxNjQ4MDkwMzEzLCJleHAiOjE2NDg2OTUxMTN9.mKL47JVwZlajifw9p8y9hD-X_60ib-t_zARHGsG8CGGD_wBCJCIrLhqO8ldYhWxeI_WNkdJGvCyvSC6z3Mdv8w
----------------------------
{
    "code": 200,
    "message": "操作成功",
    "data": {
        "id": 1,
        "username": "bear",
        "avatar": "bear.png",
        "email": "johnmin74@hotmail.com",
        "password": "96e79218965eb72c92a549dd5a330112",
        "status": 0,
        "created": "2022-03-22T12:00:00",
        "lastLogin": null
    }
}

Postman:
    GET
        localhost:8081/logout
    Headers
        Authorization: eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzUxMiJ9.eyJzdWIiOiIxIiwiaWF0IjoxNjQ4MDkwMzEzLCJleHAiOjE2NDg2OTUxMTN9.mKL47JVwZlajifw9p8y9hD-X_60ib-t_zARHGsG8CGGD_wBCJCIrLhqO8ldYhWxeI_WNkdJGvCyvSC6z3Mdv8w
----------------------------
{
    "code": 200,
    "message": "操作成功",
    "data": null
}

删除Cookie。

Postman:
    GET
        localhost:8081/user/index
----------------------------
{
    "code": 401,
    "message": "The current Subject is not authenticated.  Access denied.",
    "data": null
}