[PH2][Refactor] Creating call_tracer_wrapper.h . (grpc#37786)

[PH2][Refactor] Creating call_tracer_wrapper.h and cc and moving code as-is into it. The content of the functions or classes has not changed.
In the next few iterations, more code will come into this file.

Closes grpc#37786

COPYBARA_INTEGRATE_REVIEW=grpc#37786 from tanvi-jagtap:ph2_internal_h_split_01 31af14a
PiperOrigin-RevId: 680861154

BUILD

@@ -4763,6 +4763,7 @@ grpc_cc_library(
     name = "grpc_transport_chttp2",
     srcs = [
         "//src/core:ext/transport/chttp2/transport/bin_decoder.cc",
+        "//src/core:ext/transport/chttp2/transport/call_tracer_wrapper.cc",
         "//src/core:ext/transport/chttp2/transport/chttp2_transport.cc",
         "//src/core:ext/transport/chttp2/transport/frame_data.cc",
         "//src/core:ext/transport/chttp2/transport/frame_goaway.cc",
@@ -4776,6 +4777,7 @@ grpc_cc_library(
     ],
     hdrs = [
         "//src/core:ext/transport/chttp2/transport/bin_decoder.h",
+        "//src/core:ext/transport/chttp2/transport/call_tracer_wrapper.h",
         "//src/core:ext/transport/chttp2/transport/chttp2_transport.h",
         "//src/core:ext/transport/chttp2/transport/frame_data.h",
         "//src/core:ext/transport/chttp2/transport/frame_goaway.h",

src/core/ext/transport/chttp2/transport/call_tracer_wrapper.cc

@@ -0,0 +1,53 @@
+//
+//
+// Copyright 2024 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#include "src/core/ext/transport/chttp2/transport/call_tracer_wrapper.h"
+
+#include "src/core/ext/transport/chttp2/transport/internal.h"
+
+namespace grpc_core {
+
+void Chttp2CallTracerWrapper::RecordIncomingBytes(
+    const CallTracerInterface::TransportByteSize& transport_byte_size) {
+  // Update legacy API.
+  stream_->stats.incoming.framing_bytes += transport_byte_size.framing_bytes;
+  stream_->stats.incoming.data_bytes += transport_byte_size.data_bytes;
+  stream_->stats.incoming.header_bytes += transport_byte_size.header_bytes;
+  // Update new API.
+  if (!IsCallTracerInTransportEnabled()) return;
+  auto* call_tracer = stream_->arena->GetContext<CallTracerInterface>();
+  if (call_tracer != nullptr) {
+    call_tracer->RecordIncomingBytes(transport_byte_size);
+  }
+}
+
+void Chttp2CallTracerWrapper::RecordOutgoingBytes(
+    const CallTracerInterface::TransportByteSize& transport_byte_size) {
+  // Update legacy API.
+  stream_->stats.outgoing.framing_bytes += transport_byte_size.framing_bytes;
+  stream_->stats.outgoing.data_bytes += transport_byte_size.data_bytes;
+  stream_->stats.outgoing.header_bytes +=
+      transport_byte_size.header_bytes;  // Update new API.
+  if (!IsCallTracerInTransportEnabled()) return;
+  auto* call_tracer = stream_->arena->GetContext<CallTracerInterface>();
+  if (call_tracer != nullptr) {
+    call_tracer->RecordOutgoingBytes(transport_byte_size);
+  }
+}
+
+}  // namespace grpc_core

src/core/ext/transport/chttp2/transport/call_tracer_wrapper.h

@@ -0,0 +1,72 @@
+//
+//
+// Copyright 2024 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+
+#ifndef GRPC_SRC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_CALL_TRACER_WRAPPER_H
+#define GRPC_SRC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_CALL_TRACER_WRAPPER_H
+
+#include "src/core/lib/transport/transport.h"
+#include "src/core/telemetry/call_tracer.h"
+
+struct grpc_chttp2_stream;
+
+namespace grpc_core {
+
+// A CallTracer wrapper that updates both the legacy and new APIs for
+// transport byte sizes.
+// TODO(ctiller): This can go away as part of removing the
+// grpc_transport_stream_stats struct.
+class Chttp2CallTracerWrapper final : public CallTracerInterface {
+ public:
+  explicit Chttp2CallTracerWrapper(grpc_chttp2_stream* stream)
+      : stream_(stream) {}
+
+  void RecordIncomingBytes(
+      const TransportByteSize& transport_byte_size) override;
+  void RecordOutgoingBytes(
+      const TransportByteSize& transport_byte_size) override;
+
+  // Everything else is a no-op.
+  void RecordSendInitialMetadata(
+      grpc_metadata_batch* /*send_initial_metadata*/) override {}
+  void RecordSendTrailingMetadata(
+      grpc_metadata_batch* /*send_trailing_metadata*/) override {}
+  void RecordSendMessage(const SliceBuffer& /*send_message*/) override {}
+  void RecordSendCompressedMessage(
+      const SliceBuffer& /*send_compressed_message*/) override {}
+  void RecordReceivedInitialMetadata(
+      grpc_metadata_batch* /*recv_initial_metadata*/) override {}
+  void RecordReceivedMessage(const SliceBuffer& /*recv_message*/) override {}
+  void RecordReceivedDecompressedMessage(
+      const SliceBuffer& /*recv_decompressed_message*/) override {}
+  void RecordCancel(grpc_error_handle /*cancel_error*/) override {}
+  std::shared_ptr<TcpTracerInterface> StartNewTcpTrace() override {
+    return nullptr;
+  }
+  void RecordAnnotation(absl::string_view /*annotation*/) override {}
+  void RecordAnnotation(const Annotation& /*annotation*/) override {}
+  std::string TraceId() override { return ""; }
+  std::string SpanId() override { return ""; }
+  bool IsSampled() override { return false; }
+
+ private:
+  grpc_chttp2_stream* stream_;
+};
+
+}  // namespace grpc_core
+
+#endif  // GRPC_SRC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_CALL_TRACER_WRAPPER_H

src/core/ext/transport/chttp2/transport/chttp2_transport.cc

@@ -56,6 +56,7 @@
 #include <grpc/support/port_platform.h>
 #include <grpc/support/time.h>
 
+#include "src/core/ext/transport/chttp2/transport/call_tracer_wrapper.h"
 #include "src/core/ext/transport/chttp2/transport/context_list_entry.h"
 #include "src/core/ext/transport/chttp2/transport/flow_control.h"
 #include "src/core/ext/transport/chttp2/transport/frame_data.h"
@@ -361,34 +362,6 @@ std::string HttpAnnotation::ToString() const {
   return s;
 }
 
-void Chttp2CallTracerWrapper::RecordIncomingBytes(
-    const CallTracerInterface::TransportByteSize& transport_byte_size) {
-  // Update legacy API.
-  stream_->stats.incoming.framing_bytes += transport_byte_size.framing_bytes;
-  stream_->stats.incoming.data_bytes += transport_byte_size.data_bytes;
-  stream_->stats.incoming.header_bytes += transport_byte_size.header_bytes;
-  // Update new API.
-  if (!IsCallTracerInTransportEnabled()) return;
-  auto* call_tracer = stream_->arena->GetContext<CallTracerInterface>();
-  if (call_tracer != nullptr) {
-    call_tracer->RecordIncomingBytes(transport_byte_size);
-  }
-}
-
-void Chttp2CallTracerWrapper::RecordOutgoingBytes(
-    const CallTracerInterface::TransportByteSize& transport_byte_size) {
-  // Update legacy API.
-  stream_->stats.outgoing.framing_bytes += transport_byte_size.framing_bytes;
-  stream_->stats.outgoing.data_bytes += transport_byte_size.data_bytes;
-  stream_->stats.outgoing.header_bytes +=
-      transport_byte_size.header_bytes;  // Update new API.
-  if (!IsCallTracerInTransportEnabled()) return;
-  auto* call_tracer = stream_->arena->GetContext<CallTracerInterface>();
-  if (call_tracer != nullptr) {
-    call_tracer->RecordOutgoingBytes(transport_byte_size);
-  }
-}
-
 }  // namespace grpc_core
 
 //

src/core/ext/transport/chttp2/transport/frame_data.cc

@@ -27,6 +27,7 @@
 #include <grpc/slice_buffer.h>
 #include <grpc/support/port_platform.h>
 
+#include "src/core/ext/transport/chttp2/transport/call_tracer_wrapper.h"
 #include "src/core/ext/transport/chttp2/transport/internal.h"
 #include "src/core/lib/experiments/experiments.h"
 #include "src/core/lib/slice/slice.h"

src/core/ext/transport/chttp2/transport/frame_rst_stream.cc

@@ -30,6 +30,7 @@
 #include <grpc/slice_buffer.h>
 #include <grpc/support/port_platform.h>
 
+#include "src/core/ext/transport/chttp2/transport/call_tracer_wrapper.h"
 #include "src/core/ext/transport/chttp2/transport/internal.h"
 #include "src/core/ext/transport/chttp2/transport/legacy_frame.h"
 #include "src/core/ext/transport/chttp2/transport/ping_callbacks.h"

src/core/ext/transport/chttp2/transport/frame_window_update.cc

@@ -27,6 +27,7 @@
 
 #include <grpc/support/port_platform.h>
 
+#include "src/core/ext/transport/chttp2/transport/call_tracer_wrapper.h"
 #include "src/core/ext/transport/chttp2/transport/flow_control.h"
 #include "src/core/ext/transport/chttp2/transport/internal.h"
 #include "src/core/ext/transport/chttp2/transport/stream_lists.h"