Spring Rest ErrorHandling @ControllerAdvice / @Valid

Question

I\'m having trouble when Using @ControllerAdvice and @Valid annotations together in a REST controller.

I have a rest controller dec

Answer 1

In addition to this I had another problem on recursive validation.

The generated classes were missing a @valid annotation on the other XmlElements.

The reason for this is related to the fact that I was wrongly using the namespaces:

The plugin is configured to use a particular namespace

<arg>-XJsr303Annotations:targetNamespace=http://www.foo.com/bar</arg>

So the XSD need to have this as target namespace (e.g.):

<?xml version="1.0"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
    targetNamespace="http://www.foo.com/bar"
    xmlns:foo="http://www.foo.com/bar" >

    <xs:complexType name="XmlPassword">
        <xs:sequence>
            <xs:element name="password" type="xs:string" />
            <xs:element name="encryption" type="xs:string" />
        </xs:sequence>
    </xs:complexType>

    <xs:complexType name="XmlToken">
        <xs:sequence>
            <xs:element name="password" type="foo:XmlPassword" />
        </xs:sequence>
    </xs:complexType>

</xs:schema>

Kind regards Antonio

Answer 2

Better format of return message:

@ControllerAdvice
public class MyControllerAdvice extends ResponseEntityExceptionHandler {

@Override
protected ResponseEntity<Object> handleMethodArgumentNotValid(
        MethodArgumentNotValidException ex,
        HttpHeaders headers,
        HttpStatus status,
        WebRequest request) {
    BindingResult result = ex.getBindingResult();
    List<FieldErrorVM> fieldErrors = result.getFieldErrors().stream()
            .map(f -> new FieldErrorVM(f.getObjectName(), f.getField(), f.getCode()))
            .collect(Collectors.toList());

    return handleExceptionInternal(ex, "Method argument not valid, fieldErrors:" + fieldErrors ,new HttpHeaders(), HttpStatus.BAD_REQUEST, request);
    }

}

Answer 3

You are on the right track, but you need to override the handleMethodArgumentNotValid() instead of the handleException() method, e.g.

@ControllerAdvice
public class RestErrorHandler extends ResponseEntityExceptionHandler {

    @Override
    protected ResponseEntity<Object> handleMethodArgumentNotValid(
            MethodArgumentNotValidException exception,
            HttpHeaders headers,
            HttpStatus status,
            WebRequest request) {

        LOG.error(exception);
        String bodyOfResponse = exception.getMessage();
        return new ResponseEntity(errorMessage, headers, status);
    }
}

From the JavaDoc of MethodArgumentNotValidException:

Exception to be thrown when validation on an argument annotated with @Valid fails.

In other words, a MethodArgumentNotValidException is thrown when the validation fails. It is handled by the handleMethodArgumentNotValid() method provided by the ResponseEntityExceptionHandler, that needs to be overridden if you would like a custom implementation.