how to implement asynchronous tracking of the webclient in WebFlux.

[kin122]

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  hi ，Mr Wu.
  We want to implement asynchronous tracking of the webclient in WebFlux.
  So we try to modify the WebFluxWebClientInterceptor in spring-webflux-5.x-webclient-plugin.
  The code is as follows:

public void beforeMethod(EnhancedInstance objInst, Method method, Object[] allArguments, Class<?>[] argumentsTypes, MethodInvocationContext context) throws Throwable {
        if (allArguments[0] == null) {
            //illegal args,can't trace ignore
            return;
        }
       // ################# here are the code we injected###########################
        LOGGER.info("getSkyWalkingDynamicField-------------{}", objInst.getSkyWalkingDynamicField());
        for (int i = 0; i < allArguments.length; i++) {
            LOGGER.info("----allArguments[{}]-----{}---------", i, allArguments[i]);
        }
        ClientRequest request = (ClientRequest) allArguments[0];
        final ContextCarrier contextCarrier = new ContextCarrier();

        URI uri = request.url();
        final String requestURIString = getRequestURIString(uri);
        final String operationName = requestURIString;
        final String remotePeer = getIPAndPort(uri);
        AbstractSpan span = ContextManager.createExitSpan(operationName, contextCarrier, remotePeer);

        //set components name
        span.setComponent(ComponentsDefine.SPRING_WEBCLIENT);
        Tags.URL.set(span, uri.toString());
        Tags.HTTP.METHOD.set(span, request.method().toString());
        SpanLayer.asHttp(span);

        if (request instanceof EnhancedInstance) {
            ((EnhancedInstance) request).setSkyWalkingDynamicField(contextCarrier);
        }

        //user async interface
        span.prepareForAsync();
        ContextManager.stopSpan();

        context.setContext(span);
    }

We would like to use objInst.getSkyWalkingDynamicField() to get the traceid, but always get null.

May I ask if this method is feasible to get the traceid of the webclient ?
Or give me some suggestion，please.

[wu-sheng]

I don't know what is objInst.getSkyWalkingDynamicField() to get traceid. All values in it are set by the plugin itself. From the codes, it is used for contextCarrier.
Our doc is very clear, your question doesn't make sense.