Spring Boot 3.0 新特性 - 问题详情和错误响应

1.问题详细说明[RFC 7807]

HTTP/1.1 403 Forbidden
Content-Type: application/problem+json
Content-Language: en

{
	"status": 403,
	"type": "https://bankname.com/common-problems/low-balance",
	"title": "You not have enough balance",
	"detail": "Your current balance is 30 and you are transterring 50",
	"instance": "/account-transfer-service"
}

关键信息如下:

• status: 服务器生成的HTTP状态代码。
• type: 标识问题类型以及如何解决问题的URL。默认值 value is – about:blank.
• title: 问题的简短说明。
• detail: 问题的详细说明.
• instance: 发生此问题的服务的URL。默认值是当前请求URL。

2.Spring框架中的支持

2.1.问题详情

ProblemDetail pd = ProblemDetail.forStatusAndDetail(HttpStatus.NOT_FOUND, "message");
pd.setType(URI.create("http://my-app-host.com/errors/not-found"));
pd.setTitle("Record Not Found");

pd.setProperty("property-key", "property-value");

2.2.错误响应

2.3.错误响应异常

ProblemDetail pd = ProblemDetail.forStatusAndDetail(HttpStatus.INTERNAL_SERVER_ERROR, "Null Pointer Exception");
pd.setType(URI.create("http://my-app-host.com/errors/npe"));
pd.setTitle("Null Pointer Exception");

throw new ErrorResponseException(HttpStatus.INTERNAL_SERVER_ERROR, pd, npe);

2.4.ResponseEntityExceptionHandler

@ControllerAdvice
public class GlobalExceptionHandler extends ResponseEntityExceptionHandler {
	
	@ExceptionHandler(CustomException.class)
  public ProblemDetail handleCustomException(CustomException ex, WebRequest request) {

    ProblemDetail pd = //build object..
    return pd;
  }
}

我们可以从任何@ExceptionHandler或任何@RequestMapping方法返回ProblemDetail或ErrorResponse以呈现RFC 7807响应。

3.使用ResponseEntity发送ProblemDetail

@Value("${hostname}")
private String hostname;

@GetMapping(path = "/employees/v2/{id}")
public ResponseEntity getEmployeeById_V2(@PathVariable("id") Long id) {
  if (id < 100) {
    return ResponseEntity.ok(new Employee(id, "lokesh", "gupta", "admin@leftso.com"));
  } else {
    ProblemDetail pd = ProblemDetail
        .forStatusAndDetail(HttpStatus.NOT_FOUND, "Employee id '" + id + "' does no exist");
    pd.setType(URI.create("http://my-app-host.com/errors/not-found"));
    pd.setTitle("Record Not Found");
    pd.setProperty("hostname", hostname);
    return ResponseEntity.status(404).body(pd);
  }
}

{
    "detail": "Employee id '101' does no exist",
    "hostname": "localhost",
    "instance": "/employees/v2/101",
    "status": 404,
    "title": "Record Not Found",
    "type": "http://my-app-host.com/errors/not-found"
}

4.从REST控制器引发ErrorResponseException

@GetMapping(path = "/v3/{id}")
public ResponseEntity getEmployeeById_V3(@PathVariable("id") Long id) {
  try {
  	//somthing抛出了此异常
    throw new NullPointerException("Something was expected but it was null");
  }
  catch (NullPointerException npe) {
    ProblemDetail pd = ProblemDetail
        .forStatusAndDetail(HttpStatus.INTERNAL_SERVER_ERROR,
            "Null Pointer Exception");
    pd.setType(URI.create("http://my-app-host.com/errors/npe"));
    pd.setTitle("Null Pointer Exception");
    pd.setProperty("hostname", hostname);
    throw new ErrorResponseException(HttpStatus.NOT_FOUND, pd, npe);
  }
}

5.将ProblemDetail添加到自定义异常

public class RecordNotFoundException extends RuntimeException {
  private final String message;
  public RecordNotFoundException(String message) {
    this.message = message;
  }
}

我们从代码中的几个地方抛出这些异常。

@GetMapping(path = "/v1/{id}")
public ResponseEntity getEmployeeById_V1(@PathVariable("id") Long id) {
  if (id < 100) {
    return ResponseEntity.ok(...);
  } else {
    throw new RecordNotFoundException("Employee id '" + id + "' does no exist");
  }
}

@ControllerAdvice
public class GlobalExceptionHandler extends ResponseEntityExceptionHandler {
  @Value("${hostname}")
  private String hostname;
  @ExceptionHandler(RecordNotFoundException.class)
  public ProblemDetail handleRecordNotFoundException(RecordNotFoundException ex, WebRequest request) {
    ProblemDetail body = ProblemDetail
        .forStatusAndDetail(HttpStatusCode.valueOf(404),ex.getLocalizedMessage());
    body.setType(URI.create("http://my-app-host.com/errors/not-found"));
    body.setTitle("Record Not Found");
    body.setProperty("hostname", hostname);
    return body;
  }
}

6. 在单元测试中验证ProblemDetail响应

@Test
public void testAddEmployee_V2_FailsWhen_IncorrectId() {
  try {
    this.restTemplate.getForObject("/employees/v2/101", Employee.class);
  } catch (RestClientResponseException ex) {
    ProblemDetail pd = ex.getResponseBodyAs(ProblemDetail.class);
    assertEquals("Employee id '101' does no exist", pd.getDetail());
    assertEquals(404, pd.getStatus());
    assertEquals("Record Not Found", pd.getTitle());
    assertEquals(URI.create("http://my-app-host.com/errors/not-found"), pd.getType());
    assertEquals("localhost", pd.getProperties().get("hostname"));
  }
}

@Test
void testAddEmployeeUsingWebFlux_V2_FailsWhen_IncorrectId() {
  this.webClient.get().uri("/employees/v2/101")
      .retrieve()
      .bodyToMono(String.class)
      .doOnNext(System.out::println)
      .onErrorResume(WebClientResponseException.class, ex -> {
        ProblemDetail pd = ex.getResponseBodyAs(ProblemDetail.class);
        //assertions...
        return Mono.empty();
      })
      .block();
}

执行v3接口测试

 @Test
  public void testAddEmployee_V3_FailsWhen_IncorrectId() {
    try {
      this.restTemplate.getForObject("/employees/v3/101", Employee.class);
    } catch (RestClientResponseException ex) {
      ProblemDetail pd = ex.getResponseBodyAs(ProblemDetail.class);
      System.out.println(format(ex.getStatusCode(), ex.getResponseHeaders(), pd));
    }
  }

以上测试执行结果参考

7. 总结

标签： Spring Boot 3.0新特性 Spring 6 新特性 Spring Boot 3.0错误响应 Spring Boot 3.0

地址：https://www.leftso.com/article/1116.html