标题：Copying Current Request Information Into Feign Interceptor With Hystrix Enabled

原文地址：

https://arnoldgalovics.com/feign-interceptor-hystrix/

问题

平时我们打开了Hystrix的时候，Interceptor无效了。

怎么搞？

怎么搞呢？

这个作者给出了他的修改：

@Component
public class RequestContextHolderHystrixConcurrencyStrategy extends HystrixConcurrencyStrategy {
    private HystrixConcurrencyStrategy delegate;

    public RequestContextHolderHystrixConcurrencyStrategy() {
        this.delegate = HystrixPlugins.getInstance().getConcurrencyStrategy();
        HystrixCommandExecutionHook commandExecutionHook = HystrixPlugins.getInstance().getCommandExecutionHook();
        HystrixEventNotifier eventNotifier = HystrixPlugins.getInstance().getEventNotifier();
        HystrixMetricsPublisher metricsPublisher = HystrixPlugins.getInstance().getMetricsPublisher();
        HystrixPropertiesStrategy propertiesStrategy = HystrixPlugins.getInstance().getPropertiesStrategy();
        HystrixPlugins.reset();
        HystrixPlugins.getInstance().registerConcurrencyStrategy(this);
        HystrixPlugins.getInstance().registerCommandExecutionHook(commandExecutionHook);
        HystrixPlugins.getInstance().registerEventNotifier(eventNotifier);
        HystrixPlugins.getInstance().registerMetricsPublisher(metricsPublisher);
        HystrixPlugins.getInstance().registerPropertiesStrategy(propertiesStrategy);
    }

    @Override
    public BlockingQueue<Runnable> getBlockingQueue(int maxQueueSize) {
        return delegate != null ? delegate.getBlockingQueue(maxQueueSize) : super.getBlockingQueue(maxQueueSize);
    }

    @Override
    public <T> HystrixRequestVariable<T> getRequestVariable(HystrixRequestVariableLifecycle<T> rv) {
        return delegate != null ? delegate.getRequestVariable(rv) : super.getRequestVariable(rv);
    }

    @Override
    public ThreadPoolExecutor getThreadPool(HystrixThreadPoolKey threadPoolKey, HystrixProperty<Integer> corePoolSize,
                                            HystrixProperty<Integer> maximumPoolSize, HystrixProperty<Integer> keepAliveTime, TimeUnit unit,
                                            BlockingQueue<Runnable> workQueue) {
        return delegate != null ? delegate.getThreadPool(threadPoolKey, corePoolSize, maximumPoolSize, keepAliveTime, unit, workQueue)
                : super.getThreadPool(threadPoolKey, corePoolSize, maximumPoolSize, keepAliveTime, unit, workQueue);
    }

    @Override
    public ThreadPoolExecutor getThreadPool(HystrixThreadPoolKey threadPoolKey, HystrixThreadPoolProperties threadPoolProperties) {
        return delegate != null ? delegate.getThreadPool(threadPoolKey, threadPoolProperties) : super.getThreadPool(threadPoolKey, threadPoolProperties);
    }

    @Override
    public <T> Callable<T> wrapCallable(Callable<T> callable) {
        RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
        RequestContextHolderCallable<T> delegatingCallable = new RequestContextHolderCallable<>(callable, requestAttributes);
        return delegate != null ? delegate.wrapCallable(delegatingCallable) : super.wrapCallable(delegatingCallable);
    }
}

RequestContextHolder.java

public class RequestContextHolderCallable<V> implements Callable<V> {
    private final Callable<V> delegate;
    private final RequestAttributes originalRequestAttributes;

    public RequestContextHolderCallable(Callable<V> delegate, RequestAttributes originalRequestAttributes) {
        this.delegate = delegate;
        this.originalRequestAttributes = originalRequestAttributes;
    }

    @Override
    public V call() throws Exception {
        RequestAttributes currentRequestAttributes = RequestContextHolder.getRequestAttributes();
        try {
            RequestContextHolder.setRequestAttributes(originalRequestAttributes);
            return delegate.call();
        } finally {
            RequestContextHolder.setRequestAttributes(currentRequestAttributes);
        }
    }
}

原文请参考上方地址