Spring Boot统一REST API接口响应格式和异常处理

雨点打透心脏的1/2处 2023-07-17 15:45 11阅读 0赞

### 文章目录 ###

*  Spring Boot统一REST API接口响应格式和异常处理
 *   *  前言
     *  定义统一的接口响应格式
     *  接口调用成功时返回统一的接口响应格式
     *  发生异常时返回统一的接口响应格式
     *  参考文档

# Spring Boot统一REST API接口响应格式和异常处理 #

> 本文已过时。  
> 请参见新的示例代码：[https://github.com/cookcodeblog/spring-boot-examples/tree/master/spring-boot-rest/src/main/java/cn/xdevops/springboot/examples/bookstore][https_github.com_cookcodeblog_spring-boot-examples_tree_master_spring-boot-rest_src_main_java_cn_xdevops_springboot_examples_bookstore]

## 前言 ##

在REST API接口中，非常有必要统一接口响应格式。

示例：

{ 
      "code": 0,
      "message": "OK",
      "data": { 
      }
    }

*  code为结果编码，一般0表示成功，其它表示失败
 *  message为结果描述或错误信息
 *  data为业务数据，可以为空

## 定义统一的接口响应格式 ##

定义ApiResponse类来作为统一的接口响应对象。

@Data
    @Builder
    @Slf4j
    public class ApiResponse<T> implements Serializable { 
    
        private static final long serialVersionUID = 1L;
    
        private int code;
    
        private String message;
    
        private T data;
    
        public static <T> ApiResponse success(T data) { 
            ApiResponse response = ApiResponse.builder().code(ReturnCode.SUCCESS.getCode()).message(ReturnCode.SUCCESS.getMessage()).data(data).build();
            log.info("Success API Response: {}", response.toString());
            return response;
        }
    
        public static ApiResponse success() { 
            return success(null);
        }
    
        public static <T> ApiResponse fail(int code, String message) { 
            ApiResponse response = ApiResponse.builder().code(code).message(message).build();
            log.error("Failed API Response: {}", response.toString());
            return response;
        }
    
        public static <T> ApiResponse fail(ReturnCode returnCode) { 
            return fail(returnCode.getCode(), returnCode.getMessage());
        }
    
        public static <T> ApiResponse fail() { 
            return fail(ReturnCode.FAILED);
        }
    
        public static <T> ApiResponse fail(String message) { 
            return fail(ReturnCode.FAILED.getCode(), message);
        }
    }

定义ReturnCode枚举类来存储系统的错误代码和相应的错误信息：

@Getter
    @AllArgsConstructor
    public enum ReturnCode { 
        SUCCESS(0, "OK"),
        FAILED(-1, "Failed");
    
        private final int code;
        private final String message;
    }

后续增加系统错误代码时，只需要将新的错误代码和相应的错误信息添加到该枚举类中。

## 接口调用成功时返回统一的接口响应格式 ##

在REST API接口调用时，通过ApiResponse.success()方法返回统一的接口响应格式。

@RestController
    public class UserController { 
    
        @Autowired
        private UserMapper userMapper;
    
        @PostMapping("/user")
        public ApiResponse addUser(@RequestBody User user) { 
            userMapper.insertSelective(user);
            return ApiResponse.success();
        }
    
        @GetMapping("/user/{id}")
        public ApiResponse getUser(@PathVariable("id") String id) { 
            return ApiResponse.success(userMapper.selectByPrimaryKey(Long.valueOf(id)));
        }
    }

## 发生异常时返回统一的接口响应格式 ##

一般是先自定义一个RuntimeException类，该类中包含错误代码和相应的错误信息。

@Getter
    public class ServiceException extends  RuntimeException { 
        private int code;
    
        public ServiceException(int code, String message) { 
            super(message);
            this.code = code;
        }
    
        public ServiceException(ReturnCode returnCode) { 
            super(returnCode.getMessage());
            this.code = returnCode.getCode();
        }
    }

再定义一个Controller异常处理器来捕获Controller抛出的该RuntimeException，再通过ApiResponse.fail()方法返回统一的接口响应格式。

@Slf4j
    @ControllerAdvice
    public class ControllerExceptionHandler { 
    
        @ExceptionHandler(ServiceException.class)
        @ResponseBody
        public ApiResponse handleServiceException(ServiceException e) { 
            log.error(e.getMessage(), e);
            return ApiResponse.fail(e.getCode(), e.getMessage());
        }
    
        @ExceptionHandler(BindException.class)
        @ResponseBody
        public AjaxResult handleBindException(BindException e)
        { 
            log.error(e.getMessage(), e);
            String message = e.getAllErrors().get(0).getDefaultMessage();
            return ApiResponse.fail(message);
        }
    
        @ExceptionHandler(Exception.class)
        @ResponseBody
        public AjaxResult handleException(Exception e)
        { 
            log.error(e.getMessage(), e);
            return ApiResponse.fail(e.getMessage());
        }
    
        @ExceptionHandler(RuntimeException.class)
        @ResponseBody
        public AjaxResult handleRuntimeException(RuntimeException e)
        { 
            log.error(e.getMessage(), e);
            return ApiResponse.fail(e.getMessage());
        }
    }

## 参考文档 ##

*  [Error Handling for REST with Spring][]
 *  [@ControllerAdvice + @ExceptionHandler 全局处理 Controller 层异常][ControllerAdvice _ _ExceptionHandler _ Controller]
 *  [Understanding Spring’s @ControllerAdvice][Understanding Spring_s _ControllerAdvice]

[https_github.com_cookcodeblog_spring-boot-examples_tree_master_spring-boot-rest_src_main_java_cn_xdevops_springboot_examples_bookstore]: https://github.com/cookcodeblog/spring-boot-examples/tree/master/spring-boot-rest/src/main/java/cn/xdevops/springboot/examples/bookstore
[Error Handling for REST with Spring]: https://www.baeldung.com/exception-handling-for-rest-with-spring
[ControllerAdvice _ _ExceptionHandler _ Controller]: https://blog.csdn.net/kinginblue/article/details/70186586
[Understanding Spring_s _ControllerAdvice]: https://medium.com/@jovannypcg/understanding-springs-controlleradvice-cd96a364033f