spring Webclient and custom logger, how to keep context?

Question

I call a REST api using Webclient

i am using a customized netty HTTPClient with a loggingHandler that I use to log my call. (I got it from here WebClient - how to get request body?)

@Slf4j
@Component
public class LoggingCustomizer implements WebClientCustomizer {

    @Override public void customize(WebClient.Builder webClientBuilder) {
        HttpClient httpClient = HttpClient.create()
            .doOnRequest((httpClientRequest, connection) -> connection.addHandlerFirst(new LoggingHandler()));
        webClientBuilder.clientConnector(new ReactorClientHttpConnector(httpClient));
    }

    private static class LoggingHandler extends ChannelDuplexHandler {

        @Override public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception {
            if (msg instanceof FullHttpRequest request) {
                log.debug("DOWNSTREAM  REQUEST: METHOD: {}, URI: {}, BODY: {}, HEADERS: {}",
                    request.method(), request.uri(), request.content().toString(defaultCharset()), request.headers());
            } else if (msg instanceof HttpRequest request) {
                log.debug("DOWNSTREAM  REQUEST: METHOD: {}, URI: {}, HEADERS: {}",
                    request.method(), request.uri(), request.headers());
            } else if (msg instanceof FullHttpMessage message) {
                log.debug("DOWNSTREAM  REQUEST: BODY: {}",
                    message.content().toString(defaultCharset()));
            }
            super.write(ctx, msg, promise);
        }

        @Override public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
            if (msg instanceof FullHttpResponse response) {
                log.debug("DOWNSTREAM RESPONSE: STATUS: {}, BODY: {}, HEADERS: {}",
                    response.status().code(), response.content().toString(defaultCharset()), response.headers());
            } else if (msg instanceof HttpResponse response) {
                log.debug("DOWNSTREAM RESPONSE: STATUS: {}, HEADERS: {}",
                    response.status().code(), response.headers());
            } else if (!(msg instanceof LastHttpContent) && msg instanceof HttpContent httpContent) {
                log.debug("DOWNSTREAM RESPONSE: BODY: {}",
                    httpContent.content().toString(defaultCharset()));
            }
            super.channelRead(ctx, msg);
        }
    }

}

but i need to get My correlation_Id from the treadContext to the logger.

i have tried using a webClient with a contextwrite to copy the context so that it could be accessible in the thread.

                
                ...
                .retrieve()
                .onStatus(HttpStatus::is4xxClientError, response -> ...)
                .onStatus(HttpStatus::is5xxServerError, response -> ...)
                .bodyToMono(...))
                .contextWrite(context -> Context.of(MDC.getCopyOfContextMap()))
                .doFinally(signalType -> MDC.clear())
                .block()
                ;

but i cannot get it in the logginghandler, i have nothing in threadContext or MDC

            var context2 = MDC.getMap();
            var context = ThreadContext.getContext();
            var response = (HttpResponse) msg;

Am I doing something wrong?

spring Webclient and custom logger, how to keep context?

0 Answers0