ContentPreviewingService logs are inserted after custom logs

[sedax90]

I've added some decorators to my ServerBuilder:

        sb.decorator(LoggingService.newDecorator());

        // Add request/response preview data to logs
        sb.decorator(ContentPreviewingService.newDecorator(Integer.MAX_VALUE));

        // Add trace ID to every request/response
        sb.decorator(TraceIdDecorator::new);

        return sb.build();

With these decorators I would expect log output like this:

REQUEST LOG
MY CUSTOM LOGS...
RESPONSE LOG

but the output that i optain is:

MY CUSTOM LOGS...
REQUEST LOG
RESPONSE LOG

and request/response do not contain the traceId value that I added as a custom decorator (while all the others do).

How can I get the logs to be written in the correct order?

[ikhoon]

request/response do not contain the traceId value that I added as a custom decorator (while all the others do).

Did you set the trace ID using MDC? If so, I recommend using RequestScopedMdc as requests in Armeria are served asynchronously in an event loop.

How can I get the logs to be written in the correct order?

The request and response logs are written together, so it is difficult to inject add MY CUSTOM LOGS using a decorator.

armeria/core/src/main/java/com/linecorp/armeria/internal/common/logging/LoggingUtils.java

Lines 41 to 50 in ed16bf6

	logWriter.logRequest(requestLog);
	} catch (Throwable t) {
	logException(ctx, "request", t);
	}
	}
	if (requestLog.responseCause() != null ||
	requestLog.responseHeaders().status().isServerError() ||
	!isTransientService(ctx)) {
	try {
	logWriter.logResponse(requestLog);

One possible workaround is implementing a custom LogWriter and composing it with the default LogWriter using .andThen().

LogWriter logWriter = LogWriter.of().andThen(new LogWriter() {
    @Override
    public void logRequest(RequestOnlyLog log) {
        logger.info("MY CUSTOM LOGS...");
    }

    @Override
    public void logResponse(RequestLog log) {
        // DO NOTHING
    }
});
LoggingService.builder()
              .logWriter(logWriter)
              .newDecorator();

[sedax90]

thanks for your response, TraceID is added like this:

public class TraceIdDecorator extends SimpleDecoratingHttpService {

    public TraceIdDecorator(HttpService delegate) {
        super(delegate);
    }

    @Override
    public HttpResponse serve(ServiceRequestContext ctx, HttpRequest req) throws Exception {
        final String traceId = UUID.randomUUID().toString();

        // Salva il traceId nel contesto della richiesta
        ctx.setAttr(AttributeKey.valueOf("traceId"), traceId);

        // Aggiungi il traceId nei log
        MDC.put("traceId", traceId);

        // Esegui la richiesta
        HttpResponse response = unwrap().serve(ctx, req);

        // Rimuovi il traceId dal MDC alla fine della richiesta
        response.whenComplete().thenRun(() -> MDC.remove("traceId"));

        // Propaga il traceId nella response
        return response.mapHeaders(headers -> headers.toBuilder().set("X-Trace-ID", traceId).build());
    }
}

an my custom logs are not added via decorator but directly in my services, so inside my post/get/etc methods... and before the return