  void testRequestResponseSize(bool with_trailers) {
    NiceMock<Http::MockRequestEncoder> encoder;
    Http::ResponseDecoder* response_decoder = nullptr;

    EXPECT_CALL(cm_.thread_local_cluster_.conn_pool_, newStream(_, _))
        .WillOnce(Invoke(
            [&](Http::ResponseDecoder& decoder,
                Http::ConnectionPool::Callbacks& callbacks) -> Http::ConnectionPool::Cancellable* {
              response_decoder = &decoder;
              callbacks.onPoolReady(encoder, cm_.thread_local_cluster_.conn_pool_.host_,
                                    upstream_stream_info_, Http::Protocol::Http10);
              return nullptr;
            }));

    cm_.thread_local_cluster_.cluster_.info_->upstream_config_ =
        absl::make_optional<envoy::config::core::v3::TypedExtensionConfig>();
    envoy::extensions::upstreams::http::generic::v3::GenericConnectionPoolProto generic_config;
    cm_.thread_local_cluster_.cluster_.info_->upstream_config_.value()
        .mutable_typed_config()
        ->PackFrom(generic_config);
    callbacks_.route_->route_entry_.connect_config_ =
        absl::make_optional<RouteEntry::ConnectConfig>();

    EXPECT_CALL(cm_.thread_local_cluster_, httpConnPool(_, _, _));

    Http::TestRequestHeaderMapImpl headers;
    HttpTestUtility::addDefaultHeaders(headers);
    headers.setMethod("POST");

    EXPECT_CALL(
        cm_.thread_local_cluster_.cluster_.info_->request_response_size_stats_store_,
        deliverHistogramToSinks(Property(&Stats::Metric::name, "upstream_rq_headers_size"), 74ull));
    router_.decodeHeaders(headers, false);

    EXPECT_CALL(callbacks_.dispatcher_, createTimer_);
    EXPECT_CALL(
        cm_.thread_local_cluster_.cluster_.info_->request_response_size_stats_store_,
        deliverHistogramToSinks(Property(&Stats::Metric::name, "upstream_rq_body_size"), 5ull));
    Buffer::InstancePtr body_data(new Buffer::OwnedImpl("hello"));
    EXPECT_EQ(Http::FilterDataStatus::StopIterationNoBuffer,
              router_.decodeData(*body_data, !with_trailers));

    if (with_trailers) {
      Http::TestRequestTrailerMapImpl trailers{{"some", "trailer"}};
      router_.decodeTrailers(trailers);
    }

    EXPECT_CALL(
        cm_.thread_local_cluster_.cluster_.info_->request_response_size_stats_store_,
        deliverHistogramToSinks(Property(&Stats::Metric::name, "upstream_rs_headers_size"), 10ull));
    Http::ResponseHeaderMapPtr response_headers(
        new Http::TestResponseHeaderMapImpl{{":status", "200"}});
    // NOLINTNEXTLINE: Silence null pointer access warning
    response_decoder->decodeHeaders(std::move(response_headers), false);

    EXPECT_CALL(
        cm_.thread_local_cluster_.cluster_.info_->request_response_size_stats_store_,
        deliverHistogramToSinks(Property(&Stats::Metric::name, "upstream_rs_body_size"), 7ull));
    Buffer::OwnedImpl response_data("goodbye");
    // NOLINTNEXTLINE: Silence null pointer access warning
    response_decoder->decodeData(response_data, !with_trailers);

    if (with_trailers) {
      Http::ResponseTrailerMapPtr response_trailers(
          new Http::TestResponseTrailerMapImpl{{"some-trailer", "13"}});
      // NOLINTNEXTLINE: Silence null pointer access warning
      response_decoder->decodeTrailers(std::move(response_trailers));
    }

    router_.onDestroy();
  }
  void testRequestResponseSize(bool with_trailers) {
    NiceMock<Http::MockRequestEncoder> encoder;
    Http::ResponseDecoder* response_decoder = nullptr;

    EXPECT_CALL(cm_.thread_local_cluster_.conn_pool_, newStream(_, _))
        .WillOnce(Invoke(
            [&](Http::ResponseDecoder& decoder,
                Http::ConnectionPool::Callbacks& callbacks) -> Http::ConnectionPool::Cancellable* {
              response_decoder = &decoder;
              callbacks.onPoolReady(encoder, cm_.thread_local_cluster_.conn_pool_.host_,
                                    upstream_stream_info_, Http::Protocol::Http10);
              return nullptr;
            }));

    cm_.thread_local_cluster_.cluster_.info_->upstream_config_ =
        absl::make_optional<envoy::config::core::v3::TypedExtensionConfig>();
    envoy::extensions::upstreams::http::generic::v3::GenericConnectionPoolProto generic_config;
    cm_.thread_local_cluster_.cluster_.info_->upstream_config_.value()
        .mutable_typed_config()
        ->PackFrom(generic_config);
    callbacks_.route_->route_entry_.connect_config_ =
        absl::make_optional<RouteEntry::ConnectConfig>();

    EXPECT_CALL(cm_.thread_local_cluster_, httpConnPool(_, _, _));

    Http::TestRequestHeaderMapImpl headers;
    HttpTestUtility::addDefaultHeaders(headers);
    headers.setMethod("POST");

    EXPECT_CALL(
        cm_.thread_local_cluster_.cluster_.info_->request_response_size_stats_store_,
        deliverHistogramToSinks(Property(&Stats::Metric::name, "upstream_rq_headers_size"), 74ull));
    router_.decodeHeaders(headers, false);

    EXPECT_CALL(callbacks_.dispatcher_, createTimer_);
    EXPECT_CALL(
        cm_.thread_local_cluster_.cluster_.info_->request_response_size_stats_store_,
        deliverHistogramToSinks(Property(&Stats::Metric::name, "upstream_rq_body_size"), 5ull));
    Buffer::InstancePtr body_data(new Buffer::OwnedImpl("hello"));
    EXPECT_EQ(Http::FilterDataStatus::StopIterationNoBuffer,
              router_.decodeData(*body_data, !with_trailers));

    if (with_trailers) {
      Http::TestRequestTrailerMapImpl trailers{{"some", "trailer"}};
      router_.decodeTrailers(trailers);
    }

    EXPECT_CALL(
        cm_.thread_local_cluster_.cluster_.info_->request_response_size_stats_store_,
        deliverHistogramToSinks(Property(&Stats::Metric::name, "upstream_rs_headers_size"), 10ull));
    Http::ResponseHeaderMapPtr response_headers(
        new Http::TestResponseHeaderMapImpl{{":status", "200"}});
     
    response_decoder->decodeHeaders(std::move(response_headers), false);

    EXPECT_CALL(
        cm_.thread_local_cluster_.cluster_.info_->request_response_size_stats_store_,
        deliverHistogramToSinks(Property(&Stats::Metric::name, "upstream_rs_body_size"), 7ull));
    Buffer::OwnedImpl response_data("goodbye");
     
    response_decoder->decodeData(response_data, !with_trailers);

    if (with_trailers) {
      Http::ResponseTrailerMapPtr response_trailers(
          new Http::TestResponseTrailerMapImpl{{"some-trailer", "13"}});
       
      response_decoder->decodeTrailers(std::move(response_trailers));
    }

    router_.onDestroy();
  }