spring-cloud - 使用 Feign RequestInterceptor 无法访问的安全上下文

Question

目标是使用 RequestInterceptor 从安全上下文中附加一些数据，但问题是调用 SecurityContextHolder.getContext().getAuthentication()即使它不为null，也总是返回null(我相信100％)。

据我了解，这是因为拦截器已创建并正在其他线程中运行。

我该如何解决这个问题并从安全上下文中获取实际数据？

我的服务:

@FeignClient(value = "api", configuration = { FeignConfig.class })
public interface DocumentService {

    @RequestMapping(value = "/list", method = RequestMethod.GET)
     DocumentListOperation list();
 }

我的 FeignConfig 类:

@Bean
public RequestInterceptor requestInterceptor() {
    return new HeaderInterceptor(userService);
}

public class HeaderInterceptor implements RequestInterceptor {

    private UserService userService;

    public HeaderInterceptor(UserService userService) {
        this.userService = userService;
    }

    @Override
    public void apply(RequestTemplate requestTemplate) {
        Authentication a = SecurityContextHolder.getContext().getAuthentication()

        requestTemplate.header("authentication", a.toString());
    }
}

Answer 1

我设法弄明白了，感谢我找到的文章 here

首先你需要初始化 HystrixRequestContext HystrixRequestContext.initializeContext(); .

您必须创建自己的 Context 来存储您需要传递给 Hystrix 子线程的信息。

这是示例:

public class UserHystrixRequestContext {

    private static final HystrixRequestVariableDefault<User> userContextVariable = new HystrixRequestVariableDefault<>();

    private UserHystrixRequestContext() {}

    public static HystrixRequestVariableDefault<User> getInstance() {
        return userContextVariable;
    }
}

您必须注册新的并发策略来包装 Callable 接口(interface)

@Component
public class CustomHystrixConcurrencyStrategy extends HystrixConcurrencyStrategy {

    public CustomHystrixConcurrencyStrategy() {
        HystrixPlugins.getInstance().registerConcurrencyStrategy(this);
    }

    @Override
    public <T> Callable<T> wrapCallable(Callable<T> callable) {
        return new HystrixContextWrapper<T>(callable);
    }

    public static class HystrixContextWrapper<V> implements Callable<V> {

        private HystrixRequestContext hystrixRequestContext;
        private Callable<V> delegate;

        public HystrixContextWrapper(Callable<V> delegate) {
        this.hystrixRequestContext = HystrixRequestContext.getContextForCurrentThread();
            this.delegate = delegate;
        }

        @Override
        public V call() throws Exception {
            HystrixRequestContext existingState = HystrixRequestContext.getContextForCurrentThread();
            try {
                HystrixRequestContext.setContextOnCurrentThread(this.hystrixRequestContext);
                return this.delegate.call();
            } finally {
                HystrixRequestContext.setContextOnCurrentThread(existingState);
            }
        }
    }
}

所以在调用 Callable 对象之前，我们将新线程的上下文设置为父上下文。

完成后，您应该能够在 Hystrix 子线程中访问新定义的上下文
User = UserHystrixRequestContext.getInstance().get();
希望这会帮助某人。