Why NettyRoutingFilterInterceptor not need to stop span?How to implement traceid not to duplicate

[GuiSong01]

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• What do you want to know?
  NettyRoutingFilterInterceptor code in apm-spring-cloud-gateway-2.1.x-plugin.

public class NettyRoutingFilterInterceptor implements InstanceMethodsAroundInterceptor {
    @Override
    public void beforeMethod(EnhancedInstance objInst, Method method, Object[] allArguments, Class<?>[] argumentsTypes,
                             MethodInterceptResult result) throws Throwable {
        ServerWebExchange exchange = (ServerWebExchange) allArguments[0];
        EnhancedInstance enhancedInstance = getInstance(exchange);

        AbstractSpan span = ContextManager.createLocalSpan("SpringCloudGateway/RoutingFilter");
        if (enhancedInstance != null && enhancedInstance.getSkyWalkingDynamicField() != null) {
            ContextManager.continued((ContextSnapshot) enhancedInstance.getSkyWalkingDynamicField());
        }
        span.setComponent(SPRING_CLOUD_GATEWAY);
    }

    public static EnhancedInstance getInstance(Object o) {
        EnhancedInstance instance = null;
        if (o instanceof DefaultServerWebExchange) {
            instance = (EnhancedInstance) o;
        } else if (o instanceof ServerWebExchangeDecorator) {
            ServerWebExchange delegate = ((ServerWebExchangeDecorator) o).getDelegate();
            return getInstance(delegate);
        }
        return instance;
    }

    @Override
    public Object afterMethod(EnhancedInstance objInst, Method method, Object[] allArguments, Class<?>[] argumentsTypes,
                              Object ret) throws Throwable {
        return ret;
    }

    @Override
    public void handleMethodException(EnhancedInstance objInst, Method method, Object[] allArguments,
                                      Class<?>[] argumentsTypes, Throwable t) {
        ContextManager.activeSpan().log(t);
    }
}

afterMethod function do nothing, how to clear trace context in CONTEXT ThreadLocal.

[wu-sheng]

@GuiSong01 I pinged the original author @ascrutae. But you should know, the community usually wouldn't explain codes.

[GuiSong01]

ok,thx