Question

我正在尝试为org.springframework.validation.FieldError创建一个自定义编组器，这样我就可以避免在我的JSON响应中添加无关且可能敏感的数据，其中包括MyCommandObject.errors。

但是我的FieldError marshaller根本不工作，这就是我在initS方法下的BootStrap.groovy中所拥有的。

    def fieldErrorMarshaller = {
        log.info("field error marshaller $it")
        def returnArray = [:]

        returnArray['field'] = it.field
        returnArray['message'] = it.message

        return returnArray
    }

    JSON.registerObjectMarshaller(FieldError, fieldErrorMarshaller)

我没有看到任何明显的错误或marshaller日志记录。知道这里可能出现什么问题吗？

Answer 1

Grails注册了一个处理所有错误的ValidationErrorsMarshaller实例，因此你的FieldError marshaller永远不会被调用。

//convertAnother is not called for each error. That's the reason of your custom marshalled not been called.
for (Object o : errors.getAllErrors()) {
    if (o instanceof FieldError) {
        FieldError fe = (FieldError) o;
        writer.object();
        json.property("object", fe.getObjectName());
        json.property("field", fe.getField());
        json.property("rejected-value", fe.getRejectedValue());
        Locale locale = LocaleContextHolder.getLocale();
        if (applicationContext != null) {
            json.property("message", applicationContext.getMessage(fe, locale));
        }
        else {
        ...

查看ConvertersGrailsPlugin（插件的描述符），这被注册为Spring Bean，因此您可以创建另一个bean并使用相同的名称注册，覆盖marshalObject()以满足您的需求（不是测试过，可能需要更多代码）。

class MyErrorsMarshaller implements ObjectMarshaller<JSON>, ApplicationContextAware {
    ApplicationContext applicationContext;

    public boolean supports(Object object) {
        return object instanceof Errors;
    }

    public void marshalObject(Object object, JSON json) throws ConverterException {
    ...
    }

}

<强> resources.groovy

jsonErrorsMarshaller(MyErrorsMarshaller)

errorsJsonMarshallerRegisterer(ObjectMarshallerRegisterer) {
    marshaller = { MyErrorsMarshaller om -> }
    converterClass = grails.converters.JSON
}

ValidationErrorsMarshaller的参考。

ConvertersGrailsPlugin的参考。

Answer 2

对于任何好奇的人来说，这是我最后根据SérgioMichels的回答在Bootstrap.groovy写的验证器

def validationErrorsMarshaller = {
    return it.getAllErrors().collect {
        if (it instanceof FieldError) {
            Locale locale = LocaleContextHolder.getLocale();
            def msg = messageSource.getMessage(it, locale)

            return [ field: it.getField(), message: msg ]
        }
    }
}

JSON.registerObjectMarshaller(ValidationErrors, validationErrorsMarshaller)

我能够通过使用messageSource从原始的Java marshaller中简化这一点，这是通过将def messageSource添加到BootStrap类来注入的。

Answer 3

//usage in grails controller
render domainObject.errors as JSON

//resources.groovy
jsonErrorsMarshaller(MyErrorsMarshaller)
errorsJsonMarshallerRegisterer(ObjectMarshallerRegisterer) {
    marshaller = { MyErrorsMarshaller om -> }
    converterClass = grails.converters.JSON
}

//grails.converters.JSON marshaller class
import grails.converters.JSON
import grails.validation.ValidationErrors
import org.codehaus.groovy.grails.web.converters.exceptions.ConverterException
import org.codehaus.groovy.grails.web.converters.marshaller.ObjectMarshaller
import org.codehaus.groovy.grails.web.json.JSONWriter
import org.springframework.context.ApplicationContext
import org.springframework.context.ApplicationContextAware
import org.springframework.context.i18n.LocaleContextHolder
import org.springframework.validation.Errors
import org.springframework.validation.FieldError
import org.springframework.validation.ObjectError


class MyErrorsMarshaller implements ObjectMarshaller<JSON>, ApplicationContextAware {
    ApplicationContext applicationContext;

    public boolean supports(Object object) {
        return object instanceof Errors;
    }

    public void marshalObject(Object object, JSON json) throws ConverterException {
        JSONWriter writer = json.getWriter();
        try {
            List<ObjectError> errors = ((ValidationErrors)object).getAllErrors()
            writer.object();
            writer.key("errors").array();
            Locale locale = LocaleContextHolder.getLocale();
            for(FieldError error : errors){
                FieldError fe = (FieldError) error;
                writer.object();
                writer.key("field").value(fe.getField()).key("message").value(applicationContext.getMessage(fe, locale));
                writer.endObject();
            }
            writer.endArray();
            writer.endObject();
        } catch (ConverterException ce) {
            throw ce;
        } catch (Exception e) {
            e.printStackTrace()
            throw new ConverterException( "Error converting Bean with class " + object.getClass().getName(), e);
        }
    }
}

FieldErrors的Grails JSON编组程序

3 个答案: