从 Spring Boot 自定义验证器返回不同的 HTTP 状态码

Question

我正在使用spring-boot version:2.0.5

分级：

buildscript {
    ext {
        springBootVersion = '2.0.5.RELEASE'
    }
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
    }
}

apply plugin: 'java'
apply plugin: 'eclipse'
apply plugin: 'org.springframework.boot'
apply plugin: 'io.spring.dependency-management'

group = 'io.reflectoring'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = 11

repositories {
    mavenCentral()
}

dependencies {
    implementation('org.springframework.boot:spring-boot-starter-data-jpa')
    implementation('org.springframework.boot:spring-boot-starter-validation')
    implementation('org.springframework.boot:spring-boot-starter-web')
    runtimeOnly('com.h2database:h2')
    testImplementation('org.springframework.boot:spring-boot-starter-test')
    testImplementation('org.junit.jupiter:junit-jupiter-engine:5.0.1')

    // these dependencies are needed when running with Java 11, since they
    // are no longer part of the JDK
    implementation('javax.xml.bind:jaxb-api:2.3.1')
    implementation('org.javassist:javassist:3.23.1-GA')
}

test{
    useJUnitPlatform()
}

控制器

@RestController
class ValidateRequestBodyController {

  @PostMapping("/validateBody")
  ResponseEntity<String> validateBody(@Valid @RequestBody Input input) {
    return ResponseEntity.ok("valid");
  }

}

验证器类

class InputWithCustomValidator {

  @IpAddress
  private String ipAddress;
  
  // ...

}


class IpAddressValidator implements ConstraintValidator<IpAddress, String> {

  @Override
  public boolean isValid(String value, ConstraintValidatorContext context) {
    Pattern pattern = 
      Pattern.compile("^([0-9]{1,3})\\.([0-9]{1,3})\\.([0-9]{1,3})\\.([0-9]{1,3})$");
    Matcher matcher = pattern.matcher(value);
    //step 1
    if (!matcher.matches()) {
        return 400;
      }
    //Step 2
      if (ipAddress already in DB) {
        return 409; //conflict with other IP address
      }
      //Also I need to return different exception based on diff validations

  }
}

控制器建议

@ExceptionHandler(ValidationException.class)
public ResponseEntity<ErrorResponse> handle(ValidationException e) {
    return ResponseEntity
            .status(HttpStatus.BAD_REQUEST)
            .body(e.getMessage());
}

    @ExceptionHandler(MethodArgumentNotValidException.class)
public ResponseEntity<ErrorResponse> handleMethodArgumentNotValidException(MethodArgumentNotValidException e) {
    return ResponseEntity
            .status(HttpStatus.BAD_REQUEST)
            .body(e.getMessage());
}

如果我从验证器中抛出 customException，那么即使我有相应的 controllerAdvice，我也会收到以下错误消息，

{
  "code": "invalid_request"
    "description": "HV000028: Unexpected exception during isValid call."
}

总是，我收到 400 Bad request，因为我有一个总是返回 400 的 controllerAdvice。

我想在这里实现的是，是否有可能返回带有状态代码的 customException，或者是否有可能从验证器返回不同的状态代码？我在 StackOverflow 中看到了类似的帖子，但没有答案。我还查看了其他帖子，但我发现它没有用。

Answer 1

当前行为

• 当验证器代码抛出异常（不扩展 ConstraintDeclarationException）而不是返回 false 时，javax.validation 将异常包装在 ValidationException 中。这是验证器框架的行为，而不是 Spring 框架的问题。

• 当验证器代码抛出扩展 ConstraintDeclarationException 的异常而不是返回 false 时，javax.validation 框架会传播它。

• 如果验证器返回 false 而不是抛出异常，Spring 会将所有验证错误转换为 global errors 或 field errors 并将它们包装在 MethodArgumentNotValidException 中并抛出它。

问题

• 第二个选项有字段错误和全局错误，自定义状态码只能通过检查字段名和错误码返回。因此这是不可行的，因为可以使用该注释添加许多字段。
• 在第一个选项中，验证器中引发的自定义异常被包装在 ValidationException 中，因此无法使用特定于异常的处理程序。

可能的解决方案

• 解包不扩展ConstraintDeclarationException的特定异常并映射它

    @ExceptionHandler(ValidationException.class)
    public ResponseEntity handle(ValidationException e) {
        Throwable cause = e.getCause();
        if (cause instanceof InvalidIpException) {
            return ResponseEntity
                    .status(HttpStatus.BAD_REQUEST)//may be different code
                    .body(cause.getMessage());
        }
        if (cause instanceof InuseIpException) {
            return ResponseEntity
                    .status(HttpStatus.BAD_REQUEST)//may be different code
                    .body(cause.getMessage());
        }
        return ResponseEntity
                .status(HttpStatus.BAD_REQUEST)
                .body(e.getMessage());
    }

• 使您的特定例外扩展ConstraintDeclarationException，然后为其设置特定的处理程序。

    public class InvalidIpException extends 
                                    ConstraintDeclarationException {

    @ExceptionHandler(InvalidIpException.class)
    public ResponseEntity handle(InvalidIpException e) {
     ...
    }

参考代码

• https://github.com/hibernate/hibernate-validator/blob/master/engine/src/main/java/org/hibernate/validator/internal/engine/constraintvalidation/ConstraintTree.java#L183

Answer 2

在模型包下为Error创建一个类

@NoArgsConstructor
@Geeter
@Setter
public class ErrorMessage
{
    private int errorCode;
    private String errorMsg;
    private String documentation;

     public ErrorMessage(int errorCode,String errorMsg,String documentation)
       {
          this.errorCode=errorCode;
          this.errorMsg=errorMsg;
          this.documentation=documentation;
       }
}

在异常包下创建自定义验证异常类

public class CustomValidationException extends RuntimeException
{
          public CustomValidationException(String msg)
         {
              super(msg);
         }
}

在同一个（异常）包下创建ExceptionHandler类

@RestControllerAdvice
public class CustomValidationExceptionHandler
{
   @ExceptionHandler
   public ResponseEntity toResponse(CustomValidationException ex)
   {
        ErrorMessage errorMessage=new 
       ErrorMessage(400,ex.getMessage,"www.stackoverflow.com");
      return new ResponseEntity<ErrorMessage>(errorMessage,HttpStatus.BAD_REQUES);
   }

}

Answer 3

在完全理解问题后，以下内容将为您提供所需的内容。您可以根据需要在层次结构中添加任意数量的异常作为 IpValidationException 的子类，并根据您的业务/技术用例保留自定义 HTTP 状态代码。

public abstract class IpValidationException extends ValidationException {
    private HttpStatus status;
    private String message;

    public IpValidationException(HttpStatus status, String message) {
        this.status = status;
        this.message = message;
    }

    public HttpStatus getStatus() {
        return status;
    }

    public String getMessage() {
        return message;
    }
}

public class InvalidIpException extends IpValidationException {
    public InvalidIpException(HttpStatus status, String message) {
        super(HttpStatus.BAD_REQUEST, "Invalid IP address");
    }
}

public class InuseIpException extends IpValidationException {
    public InuseIpException(HttpStatus status, String message) {
        super(HttpStatus.CONFLICT, "IP address already in use");
    }
}

public class IpAddressValidator implements ConstraintValidator<IpAddress, String> {

    @Override
    public boolean isValid(String value, ConstraintValidatorContext context) {
        Pattern pattern =
                Pattern.compile("^([0-9]{1,3})\\.([0-9]{1,3})\\.([0-9]{1,3})\\.([0-9]{1,3})$");
        Matcher matcher = pattern.matcher(value);
        //step 1
        if (!matcher.matches()) {
            throw new InvalidIpException();
        }
        //Step 2
        if (ipAddress already in DB) {
            throw new InuseIpException(); //conflict with other IP address
        }
        //Add more checks with more exception as you need.

    }
}

// This is how your exception handler should look like
@ExceptionHandler(IpValidationException.class)
public ResponseEntity<ErrorResponse> handle(IpValidationException e) {
    return ResponseEntity
            .status(e.getStatus())
            .body(e.getMessage());
}

希望这会有所帮助！