pybind11_protobuf:

`LOG(WARNING)` `FALL BACK TO PROTOBUF SERIALIZE/PARSE` based on `ExtensionsWithUnknownFieldsPolicy`.

Low-level change in preparation for PyCLIF-pybind11 rollout.

PiperOrigin-RevId: 604380353

Author: rwgk

pybind11_protobuf/BUILD

@@ -87,9 +87,6 @@ cc_library(
     name = "check_unknown_fields",
     srcs = ["check_unknown_fields.cc"],
     hdrs = ["check_unknown_fields.h"],
-    visibility = [
-        "//visibility:private",
-    ],
     deps = [
         "@com_google_absl//absl/container:flat_hash_map",
         "@com_google_absl//absl/container:flat_hash_set",

pybind11_protobuf/check_unknown_fields.cc

@@ -183,7 +183,7 @@ void AllowUnknownFieldsFor(absl::string_view top_message_descriptor_full_name,
 
 std::optional<std::string> CheckRecursively(
     const ::google::protobuf::python::PyProto_API* py_proto_api,
-    const ::google::protobuf::Message* message, bool build_error_message_if_any) {
+    const ::google::protobuf::Message* message) {
   const auto* root_descriptor = message->GetDescriptor();
   HasUnknownFields search{py_proto_api, root_descriptor};
   if (!search.FindUnknownFieldsRecursive(message, 0u)) {
@@ -193,9 +193,6 @@ std::optional<std::string> CheckRecursively(
                                              search.FieldFQN())) != 0) {
     return std::nullopt;
   }
-  if (!build_error_message_if_any) {
-    return "";  // This indicates that an unknown field was found.
-  }
   return search.BuildErrorMessage();
 }
 

pybind11_protobuf/check_unknown_fields.h

@@ -47,7 +47,7 @@ void AllowUnknownFieldsFor(absl::string_view top_message_descriptor_full_name,
 
 std::optional<std::string> CheckRecursively(
     const ::google::protobuf::python::PyProto_API* py_proto_api,
-    const ::google::protobuf::Message* top_message, bool build_error_message_if_any);
+    const ::google::protobuf::Message* top_message);
 
 }  // namespace pybind11_protobuf::check_unknown_fields
 

pybind11_protobuf/proto_cast_util.cc

@@ -9,6 +9,7 @@
 #include <iostream>
 #include <memory>
 #include <string>
+#include <unordered_set>
 #include <utility>
 #include <vector>
 
@@ -828,14 +829,18 @@ py::handle GenericProtoCast(Message* src, py::return_value_policy policy,
 
   std::optional<std::string> unknown_field_message =
       check_unknown_fields::CheckRecursively(
-          GlobalState::instance()->py_proto_api(), src,
-          check_unknown_fields::ExtensionsWithUnknownFieldsPolicy::
-              UnknownFieldsAreDisallowed());
+          GlobalState::instance()->py_proto_api(), src);
   if (unknown_field_message) {
-    if (!unknown_field_message->empty()) {
+    if (check_unknown_fields::ExtensionsWithUnknownFieldsPolicy::
+            UnknownFieldsAreDisallowed()) {
       throw py::value_error(*unknown_field_message);
     }
-    // Fall back to serialize/parse.
+    // Emit one LOG(WARNING) per unique unknown_field_message:
+    static auto fall_back_log_shown = new std::unordered_set<std::string>();
+    if (fall_back_log_shown->insert(*unknown_field_message).second) {
+      LOG(WARNING) << "FALL BACK TO PROTOBUF SERIALIZE/PARSE: "
+                   << *unknown_field_message;
+    }
     return GenericPyProtoCast(src, policy, parent, is_const);
   }
 

pybind11_protobuf/tests/BUILD

@@ -161,6 +161,16 @@ pybind_extension(
     ],
 )
 
+EXTENSION_TEST_DEPS_COMMON = [
+    ":extension_in_other_file_in_deps_py_pb2",
+    ":extension_in_other_file_py_pb2",
+    ":extension_nest_repeated_py_pb2",
+    ":extension_py_pb2",
+    ":test_py_pb2",  # fixdeps: keep - Direct dependency needed in open-source version, see https://github.com/grpc/grpc/issues/22811
+    "@com_google_absl_py//absl/testing:absltest",
+    "@com_google_absl_py//absl/testing:parameterized",
+]
+
 py_test(
     name = "extension_test",
     srcs = ["extension_test.py"],
@@ -170,14 +180,20 @@ py_test(
     ],
     python_version = "PY3",
     srcs_version = "PY3",
-    deps = [
-        ":extension_in_other_file_in_deps_py_pb2",
-        ":extension_in_other_file_py_pb2",
-        ":extension_nest_repeated_py_pb2",
-        ":extension_py_pb2",
-        ":test_py_pb2",  # fixdeps: keep - Direct dependency needed in open-source version, see https://github.com/grpc/grpc/issues/22811
-        "@com_google_absl_py//absl/testing:absltest",
-        "@com_google_absl_py//absl/testing:parameterized",
+    deps = EXTENSION_TEST_DEPS_COMMON + ["@com_google_protobuf//:protobuf_python"],
+)
+
+py_test(
+    name = "extension_disallow_unknown_fields_test",
+    srcs = ["extension_test.py"],
+    data = [
+        ":extension_module.so",
+        ":proto_enum_module.so",
+    ],
+    main = "extension_test.py",
+    python_version = "PY3",
+    srcs_version = "PY3",
+    deps = EXTENSION_TEST_DEPS_COMMON + [
         "@com_google_protobuf//:protobuf_python",
     ],
 )

pybind11_protobuf/tests/extension_module.cc

@@ -48,6 +48,11 @@ void DefReserialize(py::module_& m, const char* py_name) {
 PYBIND11_MODULE(extension_module, m) {
   pybind11_protobuf::ImportNativeProtoCasters();
 
+  m.def("extensions_with_unknown_fields_are_disallowed", []() {
+    return pybind11_protobuf::check_unknown_fields::
+        ExtensionsWithUnknownFieldsPolicy::UnknownFieldsAreDisallowed();
+  });
+
   m.def("get_base_message", []() -> BaseMessage { return {}; });
 
   m.def(

pybind11_protobuf/tests/extension_test.py

@@ -20,6 +20,13 @@
 from pybind11_protobuf.tests import extension_pb2
 
 
+def unknown_field_exception_is_expected():
+  return (
+      api_implementation.Type() == 'cpp'
+      and m.extensions_with_unknown_fields_are_disallowed()
+  )
+
+
 def get_py_message(value=5,
                    in_other_file_in_deps_value=None,
                    in_other_file_value=None):
@@ -103,7 +110,7 @@ def test_extension_in_other_file_roundtrip(self):
 
   def test_reserialize_base_message(self):
     a = get_py_message(in_other_file_value=63)
-    if api_implementation.Type() == 'cpp':
+    if unknown_field_exception_is_expected():
       with self.assertRaises(ValueError) as ctx:
         m.reserialize_base_message(a)
       self.assertStartsWith(
@@ -127,7 +134,7 @@ def test_reserialize_nest_level2(self):
     a = extension_pb2.NestLevel2(
         nest_lvl1=extension_pb2.NestLevel1(
             base_msg=get_py_message(in_other_file_value=52)))
-    if api_implementation.Type() == 'cpp':
+    if unknown_field_exception_is_expected():
       with self.assertRaises(ValueError) as ctx:
         m.reserialize_nest_level2(a)
       self.assertStartsWith(
@@ -154,7 +161,7 @@ def test_reserialize_nest_repeated(self):
         get_py_message(in_other_file_value=74),
         get_py_message(in_other_file_value=85)
     ])
-    if api_implementation.Type() == 'cpp':
+    if unknown_field_exception_is_expected():
       with self.assertRaises(ValueError) as ctx:
         m.reserialize_nest_repeated(a)
       self.assertStartsWith(