将异常从 CXF 拦截器传播到异常映射器

Question

我有一个流程，在 CXF 客户端上我有 jaxrs-in-interceptor、provider 和 exception mapper。在我的例子中，我通过拦截器捕获了来自客户端的不良响应，然后我想中止 cxf 总线链并抛出错误。不幸的是我做不到，因为在每种情况下，拦截器抛出的异常都只被记录下来，但主要错误（错误的 json 格式）被传播到异常映射器。我想避免异常映射器，但我不知道如何。我正在使用 WebClient 来实现这样的拦截器：

@Component
public class MyInterceptor extends AbstractPhaseInterceptor<Message> {

    public MyInterceptor() {
        super(POST_STREAM);
    }

    @Override
    public void handleMessage(Message message) throws Fault {
        if (message != null) {
                //message.getExchange().setOneWay(true);
                //message.getExchange().put(Exception.class, new MyException());
                //message.getInterceptorChain().abort();
                //message.setContent(Exception.class, new MyException());
                //Endpoint ep = message.getExchange().get(Endpoint.class);
                //message.getInterceptorChain().abort();
                //if (ep.getInFaultObserver() != null) {
                //    ep.getInFaultObserver().onMessage(message);
                //}
                //throw new WebApplicationException( new MyException());

                //message.setContent(Response.class, response);
                throw new Fault(new MyException());
            }
        }

我读到我应该实施 jaxrs-filter，因为拦截器抛出的异常不会传播到异常映射器。由于 WebClient 的实现，在 java 中有什么方法可以做到这一点吗？

S client = create(url, clazz, list(jsonProvider(), providers));
WebClient.getConfig(client).getInInterceptors().add(new MyInterceptor());

我也试过在拦截器上使用不同的阶段，但也没用。

Answer 1

我一直在研究和测试你的问题。问题是 CXF 拦截器抛出的异常逃脱了 JAX-RS 流（CXF 团队的see the answer）

从拦截器生成的 Fault 可以在拦截器本身实现 handleFault 时被捕获

 public void handleFault(Message message) {
       Exception e = message.getContent(Exception.class);
 }

或者实施 FaultListener 并在 CXF 总线上注册它

WebClient.getConfig(client).getBus().getProperties().put("org.apache.cxf.logging.FaultListener",new MyFaultListener());

public class MyFaultListener implements FaultListener{
    public boolean faultOccurred(final Exception exception,final String description,final Message message) {
        //return false to avoid warning of default CXF logging interceptor
        return false;
    }
}

但是你不能return拦截器的自定义响应或向客户端响应故障。

我发现实现所需行为的解决方法包括将 Response 替换为自定义对象，该对象可以由您通常的方法调用处理，例如 exceptionMapper 参见 CXF/ JAX-RS : Return Custom response from interceptor

Into Interceptor.handleMessage 检查您需要的条件并创建具有自定义状态和实体的 Response。在此之后，停止链

public class MyInterceptor extends AbstractPhaseInterceptor<Message> {

    public MyInterceptor() {
        super(Phase.POST_STREAM);
    }

    @Override
    public void handleMessage(Message message) throws Fault {
        if (message != null) {
            //check the condition to raise the error 
            //build the custom Response replacing service call
            Response response = Response
                    .status(Response.Status.BAD_REQUEST)
                    .entity("custom error")
                    .build();
            message.getExchange().put(Response.class, response);

            //abort interceptor chain in you want to stop processing or throw a Fault (catched by handleFault)
            //message.getInterceptorChain().abort();
            //throw new Fault (new MyException());

        }

    public void handleFault(Message messageParam) {
    }
}

在创建 JAXRS 客户端时添加 ResponseExceptionMapper 作为提供者

providers.add(new ResponseExceptionMapper<WebApplicationException>() {

    @Override
    public WebApplicationException fromResponse(Response r) {
        return new WebApplicationException(r);
    }

});

YourService proxy = JAXRSClientFactory.create(url, clazz,providers);
Client client = WebClient.client(proxy);
WebClient.getConfig(client).getInInterceptors().add(new MyInterceptor());

在此之后，如果完成拦截器检查，对 proxy.yourService() 的调用将引发 WebApplicationException。您可以按需要的方式捕捉或重新抛出

try{
    proxy.yourService();
}catch (WebApplicationException e){
}

希望对您有所帮助

Answer 2

我完全同意之前的回答。我的实现看起来像：

@Component
public class ServiceFailureInterceptor extends AbstractPhaseInterceptor<Message> {

    private static final Logger LOG = LoggerFactory.getLogger(ServiceFailureInterceptor.class);

    public ServiceFailureInterceptor() {
        super(PRE_STREAM);
    }

    @Override
    public void handleMessage(Message message) {
        if (message != null) {
            int responseCode = (int) message.get(Message.RESPONSE_CODE);
                LogicException logicException = ErrorMapper.HTTP_STATUS_CODE_MAPPER.get(responseCode);
                InputStream is = b2stream(MapperUtils.json().toBytes(logicException));

                // clear old message & exchange
                Exchange exchange = message.getExchange();
                for (Class<?> contentFormat : message.getContentFormats()) {
                    message.setContent(contentFormat, null);
                }

                resetOrigInterceptorChain(message);
                resetFault(exchange);

                message.setContent(InputStream.class, is);
                Message outMessage = createOutMessage(exchange, is);
                prepareMessage(outMessage);
                prepareMessage(message);
        }
    }

    private void prepareMessage(Message message) {
        message.put(Message.REQUESTOR_ROLE, true);
        message.put(HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_JSON);
    }


    private Message createOutMessage(Exchange exchange, InputStream logicException) {
        Endpoint ep = exchange.get(Endpoint.class);
        Message outMessage = ep != null ? ep.getBinding().createMessage() : new MessageImpl();
        outMessage.setContent(InputStream.class, logicException);
        exchange.setOutMessage(outMessage);
        outMessage.setExchange(exchange);
        return outMessage;
    }

    private void resetFault(Exchange exchange) {
        exchange.put(Exception.class, null);
    }

    private void resetOrigInterceptorChain(Message message) {
        InterceptorChain chain = message.getInterceptorChain();
        if (chain != null) {
            for (Interceptor<?> interceptor : chain) {
                chain.remove(interceptor);
            }
            chain.reset();
        }
    }
}

手动设置此异常后，我将转到 ExceptionMapper 实现，其中使用我的 LogicException 并构建异常响应。当通过 WebClient 声明为提供程序时，我无法避免异常映射器，因此我决定使用它并稍后重新映射异常。

将异常从 CXF 拦截器传播到异常映射器

Propagate exception from CXF interceptor to exception mapper

java

web-services

cxf

jax-rs

interceptor