ByteBuddy, Modify Sleuth SpanCustomizer using javaagent bytebuddy - spring-boot

Question

Have a question about modifying Sleuth SpanCustomizer, I want to customize the span name and add additional span tag.
My final goal is want to implement a class like the following code to achieve the span tag/name modification, Should I just use bytebuddy to apply this piece of class into the agent OR detect and intercept SpanCustomizer Class to do the modification?
Any advice would be helpful, Thank you!
-------------------- Final goal implement this class --------------------
#Configuration
public class TracingConfig{
#Bean(name = { HttpClientRequestParser.NAME, HttpServerRequestParser.NAME })
HttpRequestParser sleuthHttpServerRequestParser() {
return (req, context, span) -> {
HttpRequestParser.DEFAULT.parse(req, context, span);
span.tag("upstream_cluster", getUpstreamCluster(req));
span.name(getOperationName(req));
};
}
#Bean(name = { HttpClientResponseParser.NAME, HttpServerResponseParser.NAME })
HttpResponseParser sleuthHttpServerResponseParser(){
return (resp, context, span) -> {
HttpResponseParser.DEFAULT.parse(resp, context, span);
span.tag("http.status_code", Integer.toString(resp.statusCode()));
span.name(getOperationName(resp.request()));
};
}
}
My current implementation is as follows:
-------------------- Premain --------------------
public static void premain(String agentArgs, Instrumentation inst) throws Exception {
AgentBuilder.Transformer transformerHttp = new AgentBuilder.Transformer() {
#Override
public DynamicType.Builder<?> transform(DynamicType.Builder<?> builder, TypeDescription typeDescription, ClassLoader classLoader, JavaModule module) {
return builder
.method(ElementMatchers.<MethodDescription>any())
.intercept(MethodDelegation.to(MyHttpAdvice.class));
}
};
AgentBuilder agentBuilder = new AgentBuilder.Default();
agentBuilder = agentBuilder.type(ElementMatchers.hasSuperType(ElementMatchers.named("javax.servlet.http.HttpServletRequest"))
.or(ElementMatchers.named("org.springframework.http.client.ClientHttpResponse"))
.or(ElementMatchers.named("org.springframework.web.reactive.function.client.ClientRequest"))
.or(ElementMatchers.named("org.springframework.web.reactive.function.client.ClientResponse"))
.or(ElementMatchers.named("org.springframework.web.reactive.function.client.WebClient"))
.or(ElementMatchers.named("javax.servlet.http.HttpServletRequest")))
.transform(transformerHttp);
agentBuilder.installOn(inst);
}
-------------------- My Http Advice --------------------
public class MyHttpAdvice {
#RuntimeType
public static Object intercept(#Origin Method method,
#AllArguments Object[] allArguments,
#SuperCall Callable<?> callable) throws Exception {
long start = System.currentTimeMillis();
for (Object allArgument : allArguments) {
if (allArgument instanceof SpanCustomizer) {
SpanCustomizer req = (SpanCustomizer) allArgument;
req.tag("test1", "test2");
req.name("test3");
System.out.println("intercept http request span customizer ------- " + req.toString());
}
return callable.call();
}
}
}
}