I want to print all request paths, post request parameters, etc. in micronuat, but when I use a filter to implement it, getBody always outputs empty. Is there any other way to achieve this function?

[chengna106]

I want to print all request paths, post request parameters, etc. in micronuat, but when I use a filter to implement it, getBody always outputs empty. Is there any other way to achieve this function?

[vonZeppelin]

Did you try setting log level of the org.slf4j.simpleLogger.log.io.micronaut.http logger to trace?

[chengna106]

That way can only print out the URL path information, but cannot print out the information of the post request

[nkwiatkowski]

Hi, In Micronaut 1, it was possible to print request path, body, headers, parameters with a simple request filter.
With Micronaut 2, it's a bit more tricky : you won't have access to the body in a request filter before the publisher is release by the controller. So I made a Netty pipeline to log requests information:

@Getter
@Setter
public class RequestToLog {

  private String uri;
  private String method;
  private String body;

}

@Slf4j
public class RequestLogger extends ChannelDuplexHandler {

  private static final int LAST_ITERATION = 2;
  public static final String REQUEST_LOGGER = "requestLogger";

  private final AtomicInteger iteration = new AtomicInteger(0);
  private final RequestToLog requestToLog = new RequestToLog();
  private List<String> blackList;
  private int maxBodyLength;

  public RequestLogger(List<String> blackList, int maxBodyLength) {
    this.blackList = blackList;
    this.maxBodyLength = maxBodyLength;
  }

  @Override
  public void channelRead(
      final ChannelHandlerContext context,
      final Object message) {
    if (context.name().equals(REQUEST_LOGGER)) {
      try {
        iteration.incrementAndGet();
        if (message instanceof DefaultHttpRequest) {
          requestToLog.setMethod(((DefaultHttpRequest) message).method().name());
          requestToLog.setUri(((DefaultHttpRequest) message).uri());
        }
        if (message instanceof DefaultLastHttpContent) {
          requestToLog.setBody(((DefaultLastHttpContent) message).content().toString(StandardCharsets.UTF_8));
        }
        if (LAST_ITERATION == iteration.get()){
          logRequest();
        }
      } catch (RuntimeException e) {
        log.trace("Unable to log request", e);
      }
    }

    context.fireChannelRead(message);
  }

  private void logRequest() {
    String uri = requestToLog.getUri();
    if (!excludeUrl(uri)) {
      StringBuilder sb = new StringBuilder();
      sb.append("METHOD : ");
      sb.append(requestToLog.getMethod());
      sb.append("; REQUEST BODY : uri=");
      sb.append(uri);
      sb.append(";");
      String body = requestToLog.getBody();
      if (StringUtils.isNotBlank(body)) {
        sb.append("payload=");
        sb.append(StringUtils.abbreviate(body, maxBodyLength));
      }
      log.info(sb.toString());
    }
  }

  private boolean excludeUrl(String uri) {
    return getUrlToExclude().stream().anyMatch(uri::matches);
  }

  public List<String> getUrlToExclude() {
    if (blackList == null) {
      blackList = new ArrayList<>();
    }
    return blackList;
  }

}

@Singleton
@Requires(property = "request.log.enable", value = "true")
public class LogRequestPipelineCustomizer
    implements BeanCreatedEventListener<ChannelPipelineCustomizer> {


  @Value("${request.log.blacklist}")
  private List<String> urlToExclude;

  @Value("${request.log.debug.body.max-length:`2048`}")
  private int debugBodyMaxLength;

  @Override
  public ChannelPipelineCustomizer onCreated(BeanCreatedEvent<ChannelPipelineCustomizer> event) {
    ChannelPipelineCustomizer customizer = event.getBean();

    if (customizer.isServerChannel()) {
      customizer.doOnConnect(pipeline -> {
        if(pipeline.context(REQUEST_LOGGER) == null) { // avoid dupe (may happen in complicated scenarios)
          pipeline.addAfter(
                  ChannelPipelineCustomizer.HANDLER_HTTP_SERVER_CODEC,
                  REQUEST_LOGGER,
                  new RequestLogger(urlToExclude, debugBodyMaxLength)
          );
        }
        return pipeline;
      });
    } else {
      customizer.doOnConnect(pipeline -> {
        if(pipeline.context(REQUEST_LOGGER) == null) { // avoid dupe (may happen in complicated scenarios)
          pipeline.addAfter(
                  ChannelPipelineCustomizer.HANDLER_HTTP_CLIENT_CODEC,
                  REQUEST_LOGGER,
                  new RequestLogger(urlToExclude, debugBodyMaxLength)
          );
        }
        return pipeline;
      });
    }
    return customizer;
  }
}