How to use the @opencensus/core.MessageEventType.RECEIVED function in @opencensus/core

return path[0] === '/' ? path : '/' + path
                }).join('')
            }
            rootSpan.addAttribute(HttpPlugin.ATTRIBUTE_HTTP_ROUTE, route)
            rootSpan.addAttribute(
                HttpPlugin.ATTRIBUTE_HTTP_USER_AGENT, userAgent)

            rootSpan.addAttribute(
                HttpPlugin.ATTRIBUTE_HTTP_STATUS_CODE,
                response.statusCode.toString())

            rootSpan.setStatus(HttpPlugin.convertTraceStatus(response.statusCode))

            // Message Event ID is not defined
            rootSpan.addMessageEvent(
                MessageEventType.RECEIVED, uuid.v4().split('-').join(''))

            rootSpan.end()
            return returned
          }

err.code.toString()
          );
        }
        rootSpan.addAttribute(GrpcPlugin.ATTRIBUTE_GRPC_ERROR_NAME, err.name);
        rootSpan.addAttribute(
          GrpcPlugin.ATTRIBUTE_GRPC_ERROR_MESSAGE,
          err.message
        );
      } else {
        rootSpan.setStatus(CanonicalCode.OK);
        rootSpan.addAttribute(
          GrpcPlugin.ATTRIBUTE_GRPC_STATUS_CODE,
          grpcTypes.status.OK.toString()
        );
      }
      rootSpan.addMessageEvent(MessageEventType.RECEIVED, 1);

      // record stats
      const parentTagCtx =
        GrpcPlugin.getTagContext(call.metadata) || new TagMap();
      parentTagCtx.set(
        serverStats.GRPC_SERVER_METHOD,
        { value: rootSpan.name },
        UNLIMITED_PROPAGATION_MD
      );
      const req = call.hasOwnProperty('request') ? call.request : {};
      GrpcPlugin.recordStats(
        rootSpan.kind,
        parentTagCtx,
        value,
        req,
        Date.now() - startTime

rootSpan.addAttribute(
                Http2Plugin.ATTRIBUTE_HTTP_HOST, `${headers[':authority']}`)
            rootSpan.addAttribute(
                Http2Plugin.ATTRIBUTE_HTTP_METHOD, `${headers[':method']}`)
            rootSpan.addAttribute(
                Http2Plugin.ATTRIBUTE_HTTP_PATH, `${headers[':path']}`)
            rootSpan.addAttribute(
                Http2Plugin.ATTRIBUTE_HTTP_ROUTE, `${headers[':path']}`)
            rootSpan.addAttribute(
                Http2Plugin.ATTRIBUTE_HTTP_USER_AGENT, userAgent)
            rootSpan.addAttribute(
                Http2Plugin.ATTRIBUTE_HTTP_STATUS_CODE, `${statusCode}`)
            rootSpan.setStatus(Http2Plugin.convertTraceStatus(statusCode))

            rootSpan.addMessageEvent(
                MessageEventType.RECEIVED, uuid.v4().split('-').join(''))

            rootSpan.end()
            return returned
          }
          return original.apply(this, arguments)

`${headers[':path']}`
            );
            rootSpan.addAttribute(
              Http2Plugin.ATTRIBUTE_HTTP_ROUTE,
              `${headers[':path']}`
            );
            rootSpan.addAttribute(
              Http2Plugin.ATTRIBUTE_HTTP_USER_AGENT,
              userAgent
            );
            rootSpan.addAttribute(
              Http2Plugin.ATTRIBUTE_HTTP_STATUS_CODE,
              `${statusCode}`
            );
            rootSpan.setStatus(Http2Plugin.parseResponseStatus(statusCode));
            rootSpan.addMessageEvent(MessageEventType.RECEIVED, 1);

            rootSpan.end();
            return returned;
          };

const adaptMessageEventType = (
  type: MessageEventType
): opencensus.proto.trace.v1.Span.TimeEvent.MessageEvent.Type => {
  switch (type) {
    case MessageEventType.SENT: {
      return opencensus.proto.trace.v1.Span.TimeEvent.MessageEvent.Type.SENT;
    }
    case MessageEventType.RECEIVED: {
      return opencensus.proto.trace.v1.Span.TimeEvent.MessageEvent.Type
        .RECEIVED;
    }
    default: {
      return opencensus.proto.trace.v1.Span.TimeEvent.MessageEvent.Type
        .TYPE_UNSPECIFIED;
    }
  }
};

}
            if (userAgent) {
              rootSpan.addAttribute(
                HttpPlugin.ATTRIBUTE_HTTP_USER_AGENT,
                userAgent
              );
            }
            rootSpan.addAttribute(
              HttpPlugin.ATTRIBUTE_HTTP_STATUS_CODE,
              response.statusCode.toString()
            );

            rootSpan.setStatus(
              HttpPlugin.parseResponseStatus(response.statusCode)
            );
            rootSpan.addMessageEvent(MessageEventType.RECEIVED, 1);

            if (plugin.options.applyCustomAttributesOnSpan) {
              plugin.options.applyCustomAttributesOnSpan(
                rootSpan,
                request,
                response
              );
            }

            tags.set(
              stats.HTTP_SERVER_METHOD,
              { value: method },
              UNLIMITED_PROPAGATION_MD
            );
            tags.set(
              stats.HTTP_SERVER_STATUS,