From 6288aa3fbbeeed14fdaa97bf62bee0953943ad53 Mon Sep 17 00:00:00 2001
From: Heba Alazzeh <hebaalazzeh@google.com>
Date: Wed, 5 Aug 2026 04:50:30 +0000
Subject: [PATCH 1/7] fix(api-core): use truthiness check in setup_request_id
 to support proto-plus messages

---
 packages/google-api-core/google/api_core/gapic_v1/requests.py | 2 +-
 packages/google-api-core/tests/unit/gapic/test_requests.py    | 4 ----
 2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/packages/google-api-core/google/api_core/gapic_v1/requests.py b/packages/google-api-core/google/api_core/gapic_v1/requests.py
index 76f5e916716d..8ce97c9cffa7 100644
--- a/packages/google-api-core/google/api_core/gapic_v1/requests.py
+++ b/packages/google-api-core/google/api_core/gapic_v1/requests.py
@@ -65,7 +65,7 @@ def setup_request_id(
                 setattr(request, field_name, str(uuid.uuid4()))
         except (AttributeError, ValueError):
             # Proto-plus messages or other objects
-            if getattr(request, field_name, None) is None:
+            if not getattr(request, field_name, None):
                 setattr(request, field_name, str(uuid.uuid4()))
     else:
         if not getattr(request, field_name, None):
diff --git a/packages/google-api-core/tests/unit/gapic/test_requests.py b/packages/google-api-core/tests/unit/gapic/test_requests.py
index a69bff5e16d7..71c7ce6d5225 100644
--- a/packages/google-api-core/tests/unit/gapic/test_requests.py
+++ b/packages/google-api-core/tests/unit/gapic/test_requests.py
@@ -53,7 +53,6 @@ def HasField(self, key):
         # MockRequest cases
         (MockRequest(), True, "uuid"),
         (MockRequest(request_id="already_set"), True, "already_set"),
-        (MockRequest(request_id=""), True, ""),
         (MockRequest(request_id=""), False, "uuid"),
         (MockRequest(request_id="already_set"), False, "already_set"),
         # MockProtoRequest cases
@@ -65,7 +64,6 @@ def HasField(self, key):
         ({}, True, "uuid"),
         ({"request_id": None}, True, "uuid"),
         ({"request_id": "already_set"}, True, "already_set"),
-        ({"request_id": ""}, True, ""),
         ({"request_id": ""}, False, "uuid"),
         ({"request_id": None}, False, "uuid"),
         ({"request_id": "already_set"}, False, "already_set"),
@@ -75,7 +73,6 @@ def HasField(self, key):
     ids=[
         "proto3_optional_not_in_request",
         "proto3_optional_already_in_request",
-        "proto3_optional_explicit_empty",
         "non_proto3_optional_empty",
         "non_proto3_optional_already_set",
         "proto3_optional_not_in_request_proto",
@@ -84,7 +81,6 @@ def HasField(self, key):
         "dict_proto3_optional_not_in_request",
         "dict_proto3_optional_value_none",
         "dict_proto3_optional_already_in_request",
-        "dict_proto3_optional_explicit_empty",
         "dict_non_proto3_optional_empty",
         "dict_non_proto3_optional_value_none",
         "dict_non_proto3_optional_already_set",

From 18914477715fec2ca138602a82e2e2fb6323e001 Mon Sep 17 00:00:00 2001
From: Heba Alazzeh <hebaalazzeh@google.com>
Date: Wed, 5 Aug 2026 18:11:41 +0000
Subject: [PATCH 2/7] update goldens & inspect proto-plus underlying protobuf
 for request_id auto-population

---
 .../%name_%version/%sub/_compat.py.j2         | 50 ++++++++++---------
 .../%name_%version/%sub/test_compat.py.j2     | 34 +++++++++++++
 .../storagebatchoperations_v1/_compat.py      | 48 ++++++++++--------
 .../storagebatchoperations_v1/test_compat.py  | 34 +++++++++++++
 .../google/api_core/gapic_v1/requests.py      | 50 +++++++++++--------
 .../tests/unit/gapic/test_requests.py         | 29 +++++++++++
 6 files changed, 179 insertions(+), 66 deletions(-)

diff --git a/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2 b/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2
index fba8615921af..0b5fab8360d8 100644
--- a/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2
+++ b/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2
@@ -24,10 +24,6 @@ from typing import Any, Dict, List, Optional, Tuple
 from typing import Union
 {% endif %}
 
-{% if has_auto_populated_fields %}
-import google.protobuf.message
-
-{% endif %}
 from google.api_core import path_template
 from google.api_core.universe import EmptyUniverseError
 from google.auth.exceptions import MutualTLSChannelError
@@ -170,7 +166,7 @@ def get_universe_domain(
 {% if has_auto_populated_fields %}
 
 def setup_request_id(
-    request: Union[google.protobuf.message.Message, dict, None],
+    request: Union[Any, dict, None],
     field_name: str,
     is_proto3_optional: bool,
 ) -> None:
@@ -184,7 +180,7 @@ def setup_request_id(
     resources).
 
     Args:
-        request (Union[google.protobuf.message.Message, dict]): The
+        request (Union[Any, dict, None]): The
             request object.
         field_name (str): The name of the field to populate.
         is_proto3_optional (bool): Whether the field is proto3 optional.
@@ -192,26 +188,34 @@ def setup_request_id(
     if request is None:
         return
 
+    should_populate = False
     if isinstance(request, dict):
         if is_proto3_optional:
-            if field_name not in request or request[field_name] is None:
-                request[field_name] = str(uuid.uuid4())
-        elif not request.get(field_name):
-            request[field_name] = str(uuid.uuid4())
-        return
-
-    if is_proto3_optional:
-        try:
-            # Pure protobuf messages
-            if not request.HasField(field_name):
-                setattr(request, field_name, str(uuid.uuid4()))
-        except (AttributeError, ValueError):
-            # Proto-plus messages or other objects
-            if not getattr(request, field_name, None):
-                setattr(request, field_name, str(uuid.uuid4()))
+            should_populate = field_name not in request or request[field_name] is None
+        else:
+            should_populate = not request.get(field_name)
     else:
-        if not getattr(request, field_name, None):
-            setattr(request, field_name, str(uuid.uuid4()))
+        is_proto_plus = hasattr(request, "_pb") and hasattr(request._pb, "HasField")
+        if is_proto3_optional:
+            if is_proto_plus:
+                try:
+                    should_populate = not request._pb.HasField(field_name)
+                except ValueError:
+                    should_populate = getattr(request, field_name, None) is None
+            else:
+                try:
+                    should_populate = not request.HasField(field_name)
+                except (AttributeError, ValueError):
+                    should_populate = getattr(request, field_name, None) is None
+        else:
+            should_populate = not getattr(request, field_name, None)
+
+    if should_populate:
+        generated_id = str(uuid.uuid4())
+        if isinstance(request, dict):
+            request[field_name] = generated_id
+        else:
+            setattr(request, field_name, generated_id)
 
 {% endif %}
 
diff --git a/packages/gapic-generator/gapic/templates/tests/unit/gapic/%name_%version/%sub/test_compat.py.j2 b/packages/gapic-generator/gapic/templates/tests/unit/gapic/%name_%version/%sub/test_compat.py.j2
index 8a923aeeef83..189502640377 100644
--- a/packages/gapic-generator/gapic/templates/tests/unit/gapic/%name_%version/%sub/test_compat.py.j2
+++ b/packages/gapic-generator/gapic/templates/tests/unit/gapic/%name_%version/%sub/test_compat.py.j2
@@ -261,6 +261,16 @@ class MockProtoRequest:
         return hasattr(self, key)
 
 
+class MockProtoPlusRequest:
+    def __init__(self, **kwargs):
+        self._pb = MockProtoRequest(**kwargs)
+        for k, v in kwargs.items():
+            setattr(self, k, v)
+
+    def __contains__(self, key):
+        return hasattr(self, key)
+
+
 class MockValueErrorRequest:
     def HasField(self, key):
         raise ValueError("Mismatched field")
@@ -268,6 +278,16 @@ class MockValueErrorRequest:
     def __contains__(self, key):
         return hasattr(self, key)
 
+
+class MockProtoPlusValueErrorRequest:
+    def __init__(self, **kwargs):
+        self._pb = MockValueErrorRequest()
+        for k, v in kwargs.items():
+            setattr(self, k, v)
+
+    def __contains__(self, key):
+        return hasattr(self, key)
+
 UUID_REGEX = r"[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}"
 
 @pytest.mark.parametrize(
@@ -275,14 +295,21 @@ UUID_REGEX = r"[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{1
     [
         (MockRequest(), True, "uuid"),
         (MockRequest(request_id="already_set"), True, "already_set"),
+        (MockRequest(request_id=""), True, ""),
         (MockRequest(request_id=""), False, "uuid"),
         (MockRequest(request_id="already_set"), False, "already_set"),
         (MockProtoRequest(), True, "uuid"),
         (MockProtoRequest(request_id="already_set"), True, "already_set"),
+        (MockProtoRequest(request_id=""), True, ""),
+        (MockProtoPlusRequest(), True, "uuid"),
+        (MockProtoPlusRequest(request_id="already_set"), True, "already_set"),
+        (MockProtoPlusRequest(request_id=""), True, ""),
         (MockValueErrorRequest(), True, "uuid"),
+        (MockProtoPlusValueErrorRequest(), True, "uuid"),
         ({}, True, "uuid"),
         ({"request_id": None}, True, "uuid"),
         ({"request_id": "already_set"}, True, "already_set"),
+        ({"request_id": ""}, True, ""),
         ({"request_id": ""}, False, "uuid"),
         ({"request_id": None}, False, "uuid"),
         ({"request_id": "already_set"}, False, "already_set"),
@@ -291,14 +318,21 @@ UUID_REGEX = r"[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{1
     ids=[
         "proto3_optional_not_in_request",
         "proto3_optional_already_in_request",
+        "proto3_optional_explicit_empty",
         "non_proto3_optional_empty",
         "non_proto3_optional_already_set",
         "proto3_optional_not_in_request_proto",
         "proto3_optional_already_in_request_proto",
+        "proto3_optional_explicit_empty_proto",
+        "proto3_optional_not_in_request_proto_plus",
+        "proto3_optional_already_in_request_proto_plus",
+        "proto3_optional_explicit_empty_proto_plus",
         "value_error_fallback",
+        "proto3_optional_value_error_fallback_proto_plus",
         "dict_proto3_optional_not_in_request",
         "dict_proto3_optional_value_none",
         "dict_proto3_optional_already_in_request",
+        "dict_proto3_optional_explicit_empty",
         "dict_non_proto3_optional_empty",
         "dict_non_proto3_optional_value_none",
         "dict_non_proto3_optional_already_set",
diff --git a/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py b/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py
index ffa58f4f04eb..0df7c0d7859c 100755
--- a/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py
+++ b/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py
@@ -22,8 +22,6 @@
 from typing import Any, Dict, List, Optional, Tuple
 from typing import Union
 
-import google.protobuf.message
-
 from google.api_core import path_template
 from google.api_core.universe import EmptyUniverseError
 from google.auth.exceptions import MutualTLSChannelError
@@ -165,7 +163,7 @@ def get_universe_domain(
 
 
 def setup_request_id(
-    request: Union[google.protobuf.message.Message, dict, None],
+    request: Union[Any, dict, None],
     field_name: str,
     is_proto3_optional: bool,
 ) -> None:
@@ -179,7 +177,7 @@ def setup_request_id(
     resources).
 
     Args:
-        request (Union[google.protobuf.message.Message, dict]): The
+        request (Union[Any, dict, None]): The
             request object.
         field_name (str): The name of the field to populate.
         is_proto3_optional (bool): Whether the field is proto3 optional.
@@ -187,26 +185,34 @@ def setup_request_id(
     if request is None:
         return
 
+    should_populate = False
     if isinstance(request, dict):
         if is_proto3_optional:
-            if field_name not in request or request[field_name] is None:
-                request[field_name] = str(uuid.uuid4())
-        elif not request.get(field_name):
-            request[field_name] = str(uuid.uuid4())
-        return
-
-    if is_proto3_optional:
-        try:
-            # Pure protobuf messages
-            if not request.HasField(field_name):
-                setattr(request, field_name, str(uuid.uuid4()))
-        except (AttributeError, ValueError):
-            # Proto-plus messages or other objects
-            if not getattr(request, field_name, None):
-                setattr(request, field_name, str(uuid.uuid4()))
+            should_populate = field_name not in request or request[field_name] is None
+        else:
+            should_populate = not request.get(field_name)
     else:
-        if not getattr(request, field_name, None):
-            setattr(request, field_name, str(uuid.uuid4()))
+        is_proto_plus = hasattr(request, "_pb") and hasattr(request._pb, "HasField")
+        if is_proto3_optional:
+            if is_proto_plus:
+                try:
+                    should_populate = not request._pb.HasField(field_name)
+                except ValueError:
+                    should_populate = getattr(request, field_name, None) is None
+            else:
+                try:
+                    should_populate = not request.HasField(field_name)
+                except (AttributeError, ValueError):
+                    should_populate = getattr(request, field_name, None) is None
+        else:
+            should_populate = not getattr(request, field_name, None)
+
+    if should_populate:
+        generated_id = str(uuid.uuid4())
+        if isinstance(request, dict):
+            request[field_name] = generated_id
+        else:
+            setattr(request, field_name, generated_id)
 
 
 def transcode_request(
diff --git a/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/tests/unit/gapic/storagebatchoperations_v1/test_compat.py b/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/tests/unit/gapic/storagebatchoperations_v1/test_compat.py
index 0fb9cbb72fd5..339e328027fd 100755
--- a/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/tests/unit/gapic/storagebatchoperations_v1/test_compat.py
+++ b/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/tests/unit/gapic/storagebatchoperations_v1/test_compat.py
@@ -260,6 +260,16 @@ def HasField(self, key):
         return hasattr(self, key)
 
 
+class MockProtoPlusRequest:
+    def __init__(self, **kwargs):
+        self._pb = MockProtoRequest(**kwargs)
+        for k, v in kwargs.items():
+            setattr(self, k, v)
+
+    def __contains__(self, key):
+        return hasattr(self, key)
+
+
 class MockValueErrorRequest:
     def HasField(self, key):
         raise ValueError("Mismatched field")
@@ -267,6 +277,16 @@ def HasField(self, key):
     def __contains__(self, key):
         return hasattr(self, key)
 
+
+class MockProtoPlusValueErrorRequest:
+    def __init__(self, **kwargs):
+        self._pb = MockValueErrorRequest()
+        for k, v in kwargs.items():
+            setattr(self, k, v)
+
+    def __contains__(self, key):
+        return hasattr(self, key)
+
 UUID_REGEX = r"[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}"
 
 @pytest.mark.parametrize(
@@ -274,14 +294,21 @@ def __contains__(self, key):
     [
         (MockRequest(), True, "uuid"),
         (MockRequest(request_id="already_set"), True, "already_set"),
+        (MockRequest(request_id=""), True, ""),
         (MockRequest(request_id=""), False, "uuid"),
         (MockRequest(request_id="already_set"), False, "already_set"),
         (MockProtoRequest(), True, "uuid"),
         (MockProtoRequest(request_id="already_set"), True, "already_set"),
+        (MockProtoRequest(request_id=""), True, ""),
+        (MockProtoPlusRequest(), True, "uuid"),
+        (MockProtoPlusRequest(request_id="already_set"), True, "already_set"),
+        (MockProtoPlusRequest(request_id=""), True, ""),
         (MockValueErrorRequest(), True, "uuid"),
+        (MockProtoPlusValueErrorRequest(), True, "uuid"),
         ({}, True, "uuid"),
         ({"request_id": None}, True, "uuid"),
         ({"request_id": "already_set"}, True, "already_set"),
+        ({"request_id": ""}, True, ""),
         ({"request_id": ""}, False, "uuid"),
         ({"request_id": None}, False, "uuid"),
         ({"request_id": "already_set"}, False, "already_set"),
@@ -290,14 +317,21 @@ def __contains__(self, key):
     ids=[
         "proto3_optional_not_in_request",
         "proto3_optional_already_in_request",
+        "proto3_optional_explicit_empty",
         "non_proto3_optional_empty",
         "non_proto3_optional_already_set",
         "proto3_optional_not_in_request_proto",
         "proto3_optional_already_in_request_proto",
+        "proto3_optional_explicit_empty_proto",
+        "proto3_optional_not_in_request_proto_plus",
+        "proto3_optional_already_in_request_proto_plus",
+        "proto3_optional_explicit_empty_proto_plus",
         "value_error_fallback",
+        "proto3_optional_value_error_fallback_proto_plus",
         "dict_proto3_optional_not_in_request",
         "dict_proto3_optional_value_none",
         "dict_proto3_optional_already_in_request",
+        "dict_proto3_optional_explicit_empty",
         "dict_non_proto3_optional_empty",
         "dict_non_proto3_optional_value_none",
         "dict_non_proto3_optional_already_set",
diff --git a/packages/google-api-core/google/api_core/gapic_v1/requests.py b/packages/google-api-core/google/api_core/gapic_v1/requests.py
index 8ce97c9cffa7..378910932975 100644
--- a/packages/google-api-core/google/api_core/gapic_v1/requests.py
+++ b/packages/google-api-core/google/api_core/gapic_v1/requests.py
@@ -22,13 +22,11 @@
 """
 
 import uuid
-from typing import Union
-
-import google.protobuf.message
+from typing import Any, Union
 
 
 def setup_request_id(
-    request: Union[google.protobuf.message.Message, dict, None],
+    request: Union[Any, dict, None],
     field_name: str,
     is_proto3_optional: bool,
 ) -> None:
@@ -42,7 +40,7 @@ def setup_request_id(
     resources).
 
     Args:
-        request (Union[google.protobuf.message.Message, dict]): The
+        request (Union[Any, dict, None]): The
             request object.
         field_name (str): The name of the field to populate.
         is_proto3_optional (bool): Whether the field is proto3 optional.
@@ -50,23 +48,31 @@ def setup_request_id(
     if request is None:
         return
 
+    should_populate = False
     if isinstance(request, dict):
         if is_proto3_optional:
-            if field_name not in request or request[field_name] is None:
-                request[field_name] = str(uuid.uuid4())
-        elif not request.get(field_name):
-            request[field_name] = str(uuid.uuid4())
-        return
-
-    if is_proto3_optional:
-        try:
-            # Pure protobuf messages
-            if not request.HasField(field_name):
-                setattr(request, field_name, str(uuid.uuid4()))
-        except (AttributeError, ValueError):
-            # Proto-plus messages or other objects
-            if not getattr(request, field_name, None):
-                setattr(request, field_name, str(uuid.uuid4()))
+            should_populate = field_name not in request or request[field_name] is None
+        else:
+            should_populate = not request.get(field_name)
     else:
-        if not getattr(request, field_name, None):
-            setattr(request, field_name, str(uuid.uuid4()))
+        is_proto_plus = hasattr(request, "_pb") and hasattr(request._pb, "HasField")
+        if is_proto3_optional:
+            if is_proto_plus:
+                try:
+                    should_populate = not request._pb.HasField(field_name)
+                except ValueError:
+                    should_populate = getattr(request, field_name, None) is None
+            else:
+                try:
+                    should_populate = not request.HasField(field_name)
+                except (AttributeError, ValueError):
+                    should_populate = getattr(request, field_name, None) is None
+        else:
+            should_populate = not getattr(request, field_name, None)
+
+    if should_populate:
+        generated_id = str(uuid.uuid4())
+        if isinstance(request, dict):
+            request[field_name] = generated_id
+        else:
+            setattr(request, field_name, generated_id)
diff --git a/packages/google-api-core/tests/unit/gapic/test_requests.py b/packages/google-api-core/tests/unit/gapic/test_requests.py
index 71c7ce6d5225..d5e0957786ef 100644
--- a/packages/google-api-core/tests/unit/gapic/test_requests.py
+++ b/packages/google-api-core/tests/unit/gapic/test_requests.py
@@ -37,11 +37,25 @@ def HasField(self, key):
         return hasattr(self, key)
 
 
+class MockProtoPlusRequest:
+    def __init__(self, **kwargs):
+        self._pb = MockProtoRequest(**kwargs)
+        for k, v in kwargs.items():
+            setattr(self, k, v)
+
+
 class MockValueErrorRequest:
     def HasField(self, key):
         raise ValueError("Mismatched field")
 
 
+class MockProtoPlusValueErrorRequest:
+    def __init__(self, **kwargs):
+        self._pb = MockValueErrorRequest()
+        for k, v in kwargs.items():
+            setattr(self, k, v)
+
+
 # --- Parameterized Test ---
 
 UUID_REGEX = r"[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}"
@@ -53,17 +67,25 @@ def HasField(self, key):
         # MockRequest cases
         (MockRequest(), True, "uuid"),
         (MockRequest(request_id="already_set"), True, "already_set"),
+        (MockRequest(request_id=""), True, ""),
         (MockRequest(request_id=""), False, "uuid"),
         (MockRequest(request_id="already_set"), False, "already_set"),
         # MockProtoRequest cases
         (MockProtoRequest(), True, "uuid"),
         (MockProtoRequest(request_id="already_set"), True, "already_set"),
+        (MockProtoRequest(request_id=""), True, ""),
+        # MockProtoPlusRequest cases
+        (MockProtoPlusRequest(), True, "uuid"),
+        (MockProtoPlusRequest(request_id="already_set"), True, "already_set"),
+        (MockProtoPlusRequest(request_id=""), True, ""),
         # ValueError case
         (MockValueErrorRequest(), True, "uuid"),
+        (MockProtoPlusValueErrorRequest(), True, "uuid"),
         # Dict cases
         ({}, True, "uuid"),
         ({"request_id": None}, True, "uuid"),
         ({"request_id": "already_set"}, True, "already_set"),
+        ({"request_id": ""}, True, ""),
         ({"request_id": ""}, False, "uuid"),
         ({"request_id": None}, False, "uuid"),
         ({"request_id": "already_set"}, False, "already_set"),
@@ -73,14 +95,21 @@ def HasField(self, key):
     ids=[
         "proto3_optional_not_in_request",
         "proto3_optional_already_in_request",
+        "proto3_optional_explicit_empty",
         "non_proto3_optional_empty",
         "non_proto3_optional_already_set",
         "proto3_optional_not_in_request_proto",
         "proto3_optional_already_in_request_proto",
+        "proto3_optional_explicit_empty_proto",
+        "proto3_optional_not_in_request_proto_plus",
+        "proto3_optional_already_in_request_proto_plus",
+        "proto3_optional_explicit_empty_proto_plus",
         "value_error_fallback",
+        "proto3_optional_value_error_fallback_proto_plus",
         "dict_proto3_optional_not_in_request",
         "dict_proto3_optional_value_none",
         "dict_proto3_optional_already_in_request",
+        "dict_proto3_optional_explicit_empty",
         "dict_non_proto3_optional_empty",
         "dict_non_proto3_optional_value_none",
         "dict_non_proto3_optional_already_set",

From 7daaa1940df255a1f63e63887f923fbbb038442c Mon Sep 17 00:00:00 2001
From: Heba Alazzeh <hebaalazzeh@google.com>
Date: Wed, 5 Aug 2026 20:40:57 +0000
Subject: [PATCH 3/7] update goldens

---
 .../%name_%version/%sub/_compat.py.j2           | 17 +++++++++++++++++
 .../cloud/storagebatchoperations_v1/_compat.py  | 17 +++++++++++++++++
 .../google/api_core/gapic_v1/requests.py        | 17 +++++++++++++++++
 3 files changed, 51 insertions(+)

diff --git a/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2 b/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2
index 0b5fab8360d8..3be859b4b689 100644
--- a/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2
+++ b/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2
@@ -188,28 +188,45 @@ def setup_request_id(
     if request is None:
         return
 
+    # 1. Evaluate whether the field is considered "unset" and needs population.
+    #
+    # According to AIP-4235, optional request ID fields must be populated
+    # if and only if they have explicit presence (`is_proto3_optional=True`)
+    # and were not set by the user (i.e. unset). Explicitly provided empty
+    # strings ('') must be preserved when `is_proto3_optional=True`.
     should_populate = False
     if isinstance(request, dict):
         if is_proto3_optional:
+            # AIP-4235: For dictionaries with optional fields, only populate
+            # if the key is missing or the value is explicitly None.
             should_populate = field_name not in request or request[field_name] is None
         else:
+            # For non-optional dict fields, populate on any missing or falsy value.
             should_populate = not request.get(field_name)
     else:
+        # Check if this is a proto-plus wrapper object containing an underlying
+        # protobuf message (`._pb`).
         is_proto_plus = hasattr(request, "_pb") and hasattr(request._pb, "HasField")
         if is_proto3_optional:
             if is_proto_plus:
                 try:
+                    # Ask the underlying protobuf message if the field was explicitly set.
                     should_populate = not request._pb.HasField(field_name)
                 except ValueError:
+                    # Fallback for non-optional fields or non-presence primitives.
                     should_populate = getattr(request, field_name, None) is None
             else:
                 try:
+                    # For pure protobuf messages, use HasField directly.
                     should_populate = not request.HasField(field_name)
                 except (AttributeError, ValueError):
+                    # For standard Python objects or mocks, only populate if strictly None.
                     should_populate = getattr(request, field_name, None) is None
         else:
+            # For non-optional fields on objects, populate on any falsy value (None or "").
             should_populate = not getattr(request, field_name, None)
 
+    # 2. Consolidate mutation to a single, clean DRY block.
     if should_populate:
         generated_id = str(uuid.uuid4())
         if isinstance(request, dict):
diff --git a/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py b/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py
index 0df7c0d7859c..47cb364e6668 100755
--- a/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py
+++ b/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py
@@ -185,28 +185,45 @@ def setup_request_id(
     if request is None:
         return
 
+    # 1. Evaluate whether the field is considered "unset" and needs population.
+    #
+    # According to AIP-4235, optional request ID fields must be populated
+    # if and only if they have explicit presence (`is_proto3_optional=True`)
+    # and were not set by the user (i.e. unset). Explicitly provided empty
+    # strings ('') must be preserved when `is_proto3_optional=True`.
     should_populate = False
     if isinstance(request, dict):
         if is_proto3_optional:
+            # AIP-4235: For dictionaries with optional fields, only populate
+            # if the key is missing or the value is explicitly None.
             should_populate = field_name not in request or request[field_name] is None
         else:
+            # For non-optional dict fields, populate on any missing or falsy value.
             should_populate = not request.get(field_name)
     else:
+        # Check if this is a proto-plus wrapper object containing an underlying
+        # protobuf message (`._pb`).
         is_proto_plus = hasattr(request, "_pb") and hasattr(request._pb, "HasField")
         if is_proto3_optional:
             if is_proto_plus:
                 try:
+                    # Ask the underlying protobuf message if the field was explicitly set.
                     should_populate = not request._pb.HasField(field_name)
                 except ValueError:
+                    # Fallback for non-optional fields or non-presence primitives.
                     should_populate = getattr(request, field_name, None) is None
             else:
                 try:
+                    # For pure protobuf messages, use HasField directly.
                     should_populate = not request.HasField(field_name)
                 except (AttributeError, ValueError):
+                    # For standard Python objects or mocks, only populate if strictly None.
                     should_populate = getattr(request, field_name, None) is None
         else:
+            # For non-optional fields on objects, populate on any falsy value (None or "").
             should_populate = not getattr(request, field_name, None)
 
+    # 2. Consolidate mutation to a single, clean DRY block.
     if should_populate:
         generated_id = str(uuid.uuid4())
         if isinstance(request, dict):
diff --git a/packages/google-api-core/google/api_core/gapic_v1/requests.py b/packages/google-api-core/google/api_core/gapic_v1/requests.py
index 378910932975..f6611b719655 100644
--- a/packages/google-api-core/google/api_core/gapic_v1/requests.py
+++ b/packages/google-api-core/google/api_core/gapic_v1/requests.py
@@ -48,28 +48,45 @@ def setup_request_id(
     if request is None:
         return
 
+    # 1. Evaluate whether the field is considered "unset" and needs population.
+    #
+    # According to AIP-4235, optional request ID fields must be populated
+    # if and only if they have explicit presence (`is_proto3_optional=True`)
+    # and were not set by the user (i.e. unset). Explicitly provided empty
+    # strings ('') must be preserved when `is_proto3_optional=True`.
     should_populate = False
     if isinstance(request, dict):
         if is_proto3_optional:
+            # AIP-4235: For dictionaries with optional fields, only populate
+            # if the key is missing or the value is explicitly None.
             should_populate = field_name not in request or request[field_name] is None
         else:
+            # For non-optional dict fields, populate on any missing or falsy value.
             should_populate = not request.get(field_name)
     else:
+        # Check if this is a proto-plus wrapper object containing an underlying
+        # protobuf message (`._pb`).
         is_proto_plus = hasattr(request, "_pb") and hasattr(request._pb, "HasField")
         if is_proto3_optional:
             if is_proto_plus:
                 try:
+                    # Ask the underlying protobuf message if the field was explicitly set.
                     should_populate = not request._pb.HasField(field_name)
                 except ValueError:
+                    # Fallback for non-optional fields or non-presence primitives.
                     should_populate = getattr(request, field_name, None) is None
             else:
                 try:
+                    # For pure protobuf messages, use HasField directly.
                     should_populate = not request.HasField(field_name)
                 except (AttributeError, ValueError):
+                    # For standard Python objects or mocks, only populate if strictly None.
                     should_populate = getattr(request, field_name, None) is None
         else:
+            # For non-optional fields on objects, populate on any falsy value (None or "").
             should_populate = not getattr(request, field_name, None)
 
+    # 2. Consolidate mutation to a single, clean DRY block.
     if should_populate:
         generated_id = str(uuid.uuid4())
         if isinstance(request, dict):

From 6e9daa53c1565bed953e7e2992cc8a6ae2186cdb Mon Sep 17 00:00:00 2001
From: Heba Alazzeh <hebaalazzeh@google.com>
Date: Wed, 5 Aug 2026 21:04:49 +0000
Subject: [PATCH 4/7] update goldens

---
 .../%name_%version/%sub/_compat.py.j2         | 57 +++++++++++-------
 .../storagebatchoperations_v1/_compat.py      | 57 +++++++++++-------
 .../google/api_core/gapic_v1/requests.py      | 58 ++++++++++++-------
 3 files changed, 109 insertions(+), 63 deletions(-)

diff --git a/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2 b/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2
index 3be859b4b689..0422be9491ba 100644
--- a/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2
+++ b/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2
@@ -17,11 +17,15 @@ import os
 import json
 {% if has_auto_populated_fields %}
 import uuid
+import google.protobuf.message
 {% endif %}
 
 from typing import Any, Dict, List, Optional, Tuple
 {% if has_auto_populated_fields %}
-from typing import Union
+from typing import TYPE_CHECKING, Union
+
+if TYPE_CHECKING:  # pragma: NO COVER
+    import proto  # type: ignore[import-untyped]
 {% endif %}
 
 from google.api_core import path_template
@@ -166,7 +170,7 @@ def get_universe_domain(
 {% if has_auto_populated_fields %}
 
 def setup_request_id(
-    request: Union[Any, dict, None],
+    request: Union[google.protobuf.message.Message, "proto.Message", dict, None],
     field_name: str,
     is_proto3_optional: bool,
 ) -> None:
@@ -180,15 +184,19 @@ def setup_request_id(
     resources).
 
     Args:
-        request (Union[Any, dict, None]): The
-            request object.
-        field_name (str): The name of the field to populate.
-        is_proto3_optional (bool): Whether the field is proto3 optional.
+        request (Union[google.protobuf.message.Message, proto.Message, dict, None]): The
+            request object or dictionary.
+        field_name (str): The name of the field to populate (e.g., "request_id").
+        is_proto3_optional (bool): Whether the field supports explicit presence
+            (defined with `optional` in proto3 syntax). When True, empty strings ("")
+            are preserved as explicit user input per AIP-4235, and UUID auto-population
+            occurs only if the field is unset. When False, any empty or falsy value is
+            populated with a UUID.
     """
     if request is None:
         return
 
-    # 1. Evaluate whether the field is considered "unset" and needs population.
+    # Evaluate whether the field is considered "unset" and needs auto-population.
     #
     # According to AIP-4235, optional request ID fields must be populated
     # if and only if they have explicit presence (`is_proto3_optional=True`)
@@ -197,36 +205,43 @@ def setup_request_id(
     should_populate = False
     if isinstance(request, dict):
         if is_proto3_optional:
-            # AIP-4235: For dictionaries with optional fields, only populate
-            # if the key is missing or the value is explicitly None.
+            # Case 1a: Dictionary request with explicit presence (`is_proto3_optional=True`).
+            # Per AIP-4235, auto-populate only if the key is completely missing from
+            # the dictionary or its value is explicitly set to None.
+            # An explicit empty string ('') must NOT be overwritten.
             should_populate = field_name not in request or request[field_name] is None
         else:
-            # For non-optional dict fields, populate on any missing or falsy value.
+            # Case 1b: Dictionary request without explicit presence (`is_proto3_optional=False`).
+            # Auto-populate if the key is missing, None, or falsy (e.g., empty string '').
             should_populate = not request.get(field_name)
     else:
-        # Check if this is a proto-plus wrapper object containing an underlying
-        # protobuf message (`._pb`).
-        is_proto_plus = hasattr(request, "_pb") and hasattr(request._pb, "HasField")
+        # Case 2: Object request (proto-plus wrapper, pure protobuf message, or mock/dict-like object).
+        pb_msg = getattr(request, "_pb", None)
+        is_proto_plus = pb_msg is not None and hasattr(pb_msg, "HasField")
         if is_proto3_optional:
-            if is_proto_plus:
+            if is_proto_plus and pb_msg is not None:
+                # Case 2a: Proto-plus message with explicit presence.
+                # `proto.Message` instances wrap an underlying C++/Python protobuf message in `._pb`.
+                # We check `pb_msg.HasField(field_name)` to determine if the field was set by the user.
                 try:
-                    # Ask the underlying protobuf message if the field was explicitly set.
-                    should_populate = not request._pb.HasField(field_name)
+                    should_populate = not pb_msg.HasField(field_name)
                 except ValueError:
-                    # Fallback for non-optional fields or non-presence primitives.
+                    # `HasField` raises ValueError if the field does not support presence (e.g., non-optional field).
+                    # Fall back to checking if the attribute value is explicitly None.
                     should_populate = getattr(request, field_name, None) is None
             else:
+                # Case 2b: Pure protobuf message or custom object with explicit presence.
                 try:
-                    # For pure protobuf messages, use HasField directly.
                     should_populate = not request.HasField(field_name)
                 except (AttributeError, ValueError):
-                    # For standard Python objects or mocks, only populate if strictly None.
+                    # Fall back for objects/mocks that do not implement `HasField` or where `HasField` fails.
                     should_populate = getattr(request, field_name, None) is None
         else:
-            # For non-optional fields on objects, populate on any falsy value (None or "").
+            # Case 2c: Object request without explicit presence (`is_proto3_optional=False`).
+            # Auto-populate if the field value is falsy (None or empty string '').
             should_populate = not getattr(request, field_name, None)
 
-    # 2. Consolidate mutation to a single, clean DRY block.
+    # Consolidate mutation to a single, clean DRY block.
     if should_populate:
         generated_id = str(uuid.uuid4())
         if isinstance(request, dict):
diff --git a/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py b/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py
index 47cb364e6668..ad9a16eacf3b 100755
--- a/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py
+++ b/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py
@@ -18,9 +18,13 @@
 import os
 import json
 import uuid
+import google.protobuf.message
 
 from typing import Any, Dict, List, Optional, Tuple
-from typing import Union
+from typing import TYPE_CHECKING, Union
+
+if TYPE_CHECKING:  # pragma: NO COVER
+    import proto  # type: ignore[import-untyped]
 
 from google.api_core import path_template
 from google.api_core.universe import EmptyUniverseError
@@ -163,7 +167,7 @@ def get_universe_domain(
 
 
 def setup_request_id(
-    request: Union[Any, dict, None],
+    request: Union[google.protobuf.message.Message, "proto.Message", dict, None],
     field_name: str,
     is_proto3_optional: bool,
 ) -> None:
@@ -177,15 +181,19 @@ def setup_request_id(
     resources).
 
     Args:
-        request (Union[Any, dict, None]): The
-            request object.
-        field_name (str): The name of the field to populate.
-        is_proto3_optional (bool): Whether the field is proto3 optional.
+        request (Union[google.protobuf.message.Message, proto.Message, dict, None]): The
+            request object or dictionary.
+        field_name (str): The name of the field to populate (e.g., "request_id").
+        is_proto3_optional (bool): Whether the field supports explicit presence
+            (defined with `optional` in proto3 syntax). When True, empty strings ("")
+            are preserved as explicit user input per AIP-4235, and UUID auto-population
+            occurs only if the field is unset. When False, any empty or falsy value is
+            populated with a UUID.
     """
     if request is None:
         return
 
-    # 1. Evaluate whether the field is considered "unset" and needs population.
+    # Evaluate whether the field is considered "unset" and needs auto-population.
     #
     # According to AIP-4235, optional request ID fields must be populated
     # if and only if they have explicit presence (`is_proto3_optional=True`)
@@ -194,36 +202,43 @@ def setup_request_id(
     should_populate = False
     if isinstance(request, dict):
         if is_proto3_optional:
-            # AIP-4235: For dictionaries with optional fields, only populate
-            # if the key is missing or the value is explicitly None.
+            # Case 1a: Dictionary request with explicit presence (`is_proto3_optional=True`).
+            # Per AIP-4235, auto-populate only if the key is completely missing from
+            # the dictionary or its value is explicitly set to None.
+            # An explicit empty string ('') must NOT be overwritten.
             should_populate = field_name not in request or request[field_name] is None
         else:
-            # For non-optional dict fields, populate on any missing or falsy value.
+            # Case 1b: Dictionary request without explicit presence (`is_proto3_optional=False`).
+            # Auto-populate if the key is missing, None, or falsy (e.g., empty string '').
             should_populate = not request.get(field_name)
     else:
-        # Check if this is a proto-plus wrapper object containing an underlying
-        # protobuf message (`._pb`).
-        is_proto_plus = hasattr(request, "_pb") and hasattr(request._pb, "HasField")
+        # Case 2: Object request (proto-plus wrapper, pure protobuf message, or mock/dict-like object).
+        pb_msg = getattr(request, "_pb", None)
+        is_proto_plus = pb_msg is not None and hasattr(pb_msg, "HasField")
         if is_proto3_optional:
-            if is_proto_plus:
+            if is_proto_plus and pb_msg is not None:
+                # Case 2a: Proto-plus message with explicit presence.
+                # `proto.Message` instances wrap an underlying C++/Python protobuf message in `._pb`.
+                # We check `pb_msg.HasField(field_name)` to determine if the field was set by the user.
                 try:
-                    # Ask the underlying protobuf message if the field was explicitly set.
-                    should_populate = not request._pb.HasField(field_name)
+                    should_populate = not pb_msg.HasField(field_name)
                 except ValueError:
-                    # Fallback for non-optional fields or non-presence primitives.
+                    # `HasField` raises ValueError if the field does not support presence (e.g., non-optional field).
+                    # Fall back to checking if the attribute value is explicitly None.
                     should_populate = getattr(request, field_name, None) is None
             else:
+                # Case 2b: Pure protobuf message or custom object with explicit presence.
                 try:
-                    # For pure protobuf messages, use HasField directly.
                     should_populate = not request.HasField(field_name)
                 except (AttributeError, ValueError):
-                    # For standard Python objects or mocks, only populate if strictly None.
+                    # Fall back for objects/mocks that do not implement `HasField` or where `HasField` fails.
                     should_populate = getattr(request, field_name, None) is None
         else:
-            # For non-optional fields on objects, populate on any falsy value (None or "").
+            # Case 2c: Object request without explicit presence (`is_proto3_optional=False`).
+            # Auto-populate if the field value is falsy (None or empty string '').
             should_populate = not getattr(request, field_name, None)
 
-    # 2. Consolidate mutation to a single, clean DRY block.
+    # Consolidate mutation to a single, clean DRY block.
     if should_populate:
         generated_id = str(uuid.uuid4())
         if isinstance(request, dict):
diff --git a/packages/google-api-core/google/api_core/gapic_v1/requests.py b/packages/google-api-core/google/api_core/gapic_v1/requests.py
index f6611b719655..146a809609d3 100644
--- a/packages/google-api-core/google/api_core/gapic_v1/requests.py
+++ b/packages/google-api-core/google/api_core/gapic_v1/requests.py
@@ -22,11 +22,16 @@
 """
 
 import uuid
-from typing import Any, Union
+from typing import TYPE_CHECKING, Any, Union
+
+import google.protobuf.message
+
+if TYPE_CHECKING:  # pragma: NO COVER
+    import proto  # type: ignore[import-untyped]
 
 
 def setup_request_id(
-    request: Union[Any, dict, None],
+    request: Union[google.protobuf.message.Message, "proto.Message", dict, None],
     field_name: str,
     is_proto3_optional: bool,
 ) -> None:
@@ -40,15 +45,19 @@ def setup_request_id(
     resources).
 
     Args:
-        request (Union[Any, dict, None]): The
-            request object.
-        field_name (str): The name of the field to populate.
-        is_proto3_optional (bool): Whether the field is proto3 optional.
+        request (Union[google.protobuf.message.Message, proto.Message, dict, None]): The
+            request object or dictionary.
+        field_name (str): The name of the field to populate (e.g., "request_id").
+        is_proto3_optional (bool): Whether the field supports explicit presence
+            (defined with `optional` in proto3 syntax). When True, empty strings ("")
+            are preserved as explicit user input per AIP-4235, and UUID auto-population
+            occurs only if the field is unset. When False, any empty or falsy value is
+            populated with a UUID.
     """
     if request is None:
         return
 
-    # 1. Evaluate whether the field is considered "unset" and needs population.
+    # Evaluate whether the field is considered "unset" and needs auto-population.
     #
     # According to AIP-4235, optional request ID fields must be populated
     # if and only if they have explicit presence (`is_proto3_optional=True`)
@@ -57,36 +66,43 @@ def setup_request_id(
     should_populate = False
     if isinstance(request, dict):
         if is_proto3_optional:
-            # AIP-4235: For dictionaries with optional fields, only populate
-            # if the key is missing or the value is explicitly None.
+            # Case 1a: Dictionary request with explicit presence (`is_proto3_optional=True`).
+            # Per AIP-4235, auto-populate only if the key is completely missing from
+            # the dictionary or its value is explicitly set to None.
+            # An explicit empty string ('') must NOT be overwritten.
             should_populate = field_name not in request or request[field_name] is None
         else:
-            # For non-optional dict fields, populate on any missing or falsy value.
+            # Case 1b: Dictionary request without explicit presence (`is_proto3_optional=False`).
+            # Auto-populate if the key is missing, None, or falsy (e.g., empty string '').
             should_populate = not request.get(field_name)
     else:
-        # Check if this is a proto-plus wrapper object containing an underlying
-        # protobuf message (`._pb`).
-        is_proto_plus = hasattr(request, "_pb") and hasattr(request._pb, "HasField")
+        # Case 2: Object request (proto-plus wrapper, pure protobuf message, or mock/dict-like object).
+        pb_msg = getattr(request, "_pb", None)
+        is_proto_plus = pb_msg is not None and hasattr(pb_msg, "HasField")
         if is_proto3_optional:
-            if is_proto_plus:
+            if is_proto_plus and pb_msg is not None:
+                # Case 2a: Proto-plus message with explicit presence.
+                # `proto.Message` instances wrap an underlying C++/Python protobuf message in `._pb`.
+                # We check `pb_msg.HasField(field_name)` to determine if the field was set by the user.
                 try:
-                    # Ask the underlying protobuf message if the field was explicitly set.
-                    should_populate = not request._pb.HasField(field_name)
+                    should_populate = not pb_msg.HasField(field_name)
                 except ValueError:
-                    # Fallback for non-optional fields or non-presence primitives.
+                    # `HasField` raises ValueError if the field does not support presence (e.g., non-optional field).
+                    # Fall back to checking if the attribute value is explicitly None.
                     should_populate = getattr(request, field_name, None) is None
             else:
+                # Case 2b: Pure protobuf message or custom object with explicit presence.
                 try:
-                    # For pure protobuf messages, use HasField directly.
                     should_populate = not request.HasField(field_name)
                 except (AttributeError, ValueError):
-                    # For standard Python objects or mocks, only populate if strictly None.
+                    # Fall back for objects/mocks that do not implement `HasField` or where `HasField` fails.
                     should_populate = getattr(request, field_name, None) is None
         else:
-            # For non-optional fields on objects, populate on any falsy value (None or "").
+            # Case 2c: Object request without explicit presence (`is_proto3_optional=False`).
+            # Auto-populate if the field value is falsy (None or empty string '').
             should_populate = not getattr(request, field_name, None)
 
-    # 2. Consolidate mutation to a single, clean DRY block.
+    # Consolidate mutation to a single, clean DRY block.
     if should_populate:
         generated_id = str(uuid.uuid4())
         if isinstance(request, dict):

From c6bae7bbdfefba2e9056f29e1c766bd74079b916 Mon Sep 17 00:00:00 2001
From: Heba Alazzeh <hebaalazzeh@google.com>
Date: Wed, 5 Aug 2026 21:14:17 +0000
Subject: [PATCH 5/7] remove unsued import

---
 packages/google-api-core/google/api_core/gapic_v1/requests.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/google-api-core/google/api_core/gapic_v1/requests.py b/packages/google-api-core/google/api_core/gapic_v1/requests.py
index 146a809609d3..eedabfa56842 100644
--- a/packages/google-api-core/google/api_core/gapic_v1/requests.py
+++ b/packages/google-api-core/google/api_core/gapic_v1/requests.py
@@ -22,7 +22,7 @@
 """
 
 import uuid
-from typing import TYPE_CHECKING, Any, Union
+from typing import TYPE_CHECKING, Union
 
 import google.protobuf.message
 

From 526ff10569cd6debec78eb903c3fa675e6063bf6 Mon Sep 17 00:00:00 2001
From: Heba Alazzeh <hebaalazzeh@google.com>
Date: Wed, 5 Aug 2026 23:42:41 +0000
Subject: [PATCH 6/7] update goldens

---
 .../%name_%version/%sub/_compat.py.j2         | 34 ++++++-------------
 .../%name_%version/%sub/test_compat.py.j2     | 12 -------
 .../storagebatchoperations_v1/_compat.py      | 34 ++++++-------------
 .../storagebatchoperations_v1/test_compat.py  | 12 -------
 .../google/api_core/gapic_v1/requests.py      | 34 ++++++-------------
 5 files changed, 33 insertions(+), 93 deletions(-)

diff --git a/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2 b/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2
index 0422be9491ba..8b81732192d7 100644
--- a/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2
+++ b/packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/_compat.py.j2
@@ -215,33 +215,21 @@ def setup_request_id(
             # Auto-populate if the key is missing, None, or falsy (e.g., empty string '').
             should_populate = not request.get(field_name)
     else:
-        # Case 2: Object request (proto-plus wrapper, pure protobuf message, or mock/dict-like object).
-        pb_msg = getattr(request, "_pb", None)
-        is_proto_plus = pb_msg is not None and hasattr(pb_msg, "HasField")
+        # Case 2: Object request (proto-plus wrapper or pure protobuf message).
         if is_proto3_optional:
-            if is_proto_plus and pb_msg is not None:
-                # Case 2a: Proto-plus message with explicit presence.
-                # `proto.Message` instances wrap an underlying C++/Python protobuf message in `._pb`.
-                # We check `pb_msg.HasField(field_name)` to determine if the field was set by the user.
-                try:
-                    should_populate = not pb_msg.HasField(field_name)
-                except ValueError:
-                    # `HasField` raises ValueError if the field does not support presence (e.g., non-optional field).
-                    # Fall back to checking if the attribute value is explicitly None.
-                    should_populate = getattr(request, field_name, None) is None
-            else:
-                # Case 2b: Pure protobuf message or custom object with explicit presence.
-                try:
-                    should_populate = not request.HasField(field_name)
-                except (AttributeError, ValueError):
-                    # Fall back for objects/mocks that do not implement `HasField` or where `HasField` fails.
-                    should_populate = getattr(request, field_name, None) is None
+            # Extract the protobuf from proto-plus if wrapped.
+            pure_pb: google.protobuf.message.Message = getattr(request, "_pb", request)
+            try:
+                should_populate = not pure_pb.HasField(field_name)
+            except (AttributeError, ValueError):
+                # Fall back if `HasField` fails or is unsupported.
+                should_populate = getattr(pure_pb, field_name, None) is None
         else:
-            # Case 2c: Object request without explicit presence (`is_proto3_optional=False`).
+            # Case 2b: Object request without explicit presence (`is_proto3_optional=False`).
             # Auto-populate if the field value is falsy (None or empty string '').
-            should_populate = not getattr(request, field_name, None)
+            should_populate = not bool(getattr(request, field_name, False))
 
-    # Consolidate mutation to a single, clean DRY block.
+    # If the field was found to be empty, set random id
     if should_populate:
         generated_id = str(uuid.uuid4())
         if isinstance(request, dict):
diff --git a/packages/gapic-generator/gapic/templates/tests/unit/gapic/%name_%version/%sub/test_compat.py.j2 b/packages/gapic-generator/gapic/templates/tests/unit/gapic/%name_%version/%sub/test_compat.py.j2
index 189502640377..d972c5d812d5 100644
--- a/packages/gapic-generator/gapic/templates/tests/unit/gapic/%name_%version/%sub/test_compat.py.j2
+++ b/packages/gapic-generator/gapic/templates/tests/unit/gapic/%name_%version/%sub/test_compat.py.j2
@@ -248,9 +248,6 @@ class MockRequest:
         for k, v in kwargs.items():
             setattr(self, k, v)
 
-    def __contains__(self, key):
-        return hasattr(self, key)
-
 
 class MockProtoRequest:
     def __init__(self, **kwargs):
@@ -267,17 +264,11 @@ class MockProtoPlusRequest:
         for k, v in kwargs.items():
             setattr(self, k, v)
 
-    def __contains__(self, key):
-        return hasattr(self, key)
-
 
 class MockValueErrorRequest:
     def HasField(self, key):
         raise ValueError("Mismatched field")
 
-    def __contains__(self, key):
-        return hasattr(self, key)
-
 
 class MockProtoPlusValueErrorRequest:
     def __init__(self, **kwargs):
@@ -285,9 +276,6 @@ class MockProtoPlusValueErrorRequest:
         for k, v in kwargs.items():
             setattr(self, k, v)
 
-    def __contains__(self, key):
-        return hasattr(self, key)
-
 UUID_REGEX = r"[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}"
 
 @pytest.mark.parametrize(
diff --git a/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py b/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py
index ad9a16eacf3b..7f7a2a0a1cf6 100755
--- a/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py
+++ b/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/_compat.py
@@ -212,33 +212,21 @@ def setup_request_id(
             # Auto-populate if the key is missing, None, or falsy (e.g., empty string '').
             should_populate = not request.get(field_name)
     else:
-        # Case 2: Object request (proto-plus wrapper, pure protobuf message, or mock/dict-like object).
-        pb_msg = getattr(request, "_pb", None)
-        is_proto_plus = pb_msg is not None and hasattr(pb_msg, "HasField")
+        # Case 2: Object request (proto-plus wrapper or pure protobuf message).
         if is_proto3_optional:
-            if is_proto_plus and pb_msg is not None:
-                # Case 2a: Proto-plus message with explicit presence.
-                # `proto.Message` instances wrap an underlying C++/Python protobuf message in `._pb`.
-                # We check `pb_msg.HasField(field_name)` to determine if the field was set by the user.
-                try:
-                    should_populate = not pb_msg.HasField(field_name)
-                except ValueError:
-                    # `HasField` raises ValueError if the field does not support presence (e.g., non-optional field).
-                    # Fall back to checking if the attribute value is explicitly None.
-                    should_populate = getattr(request, field_name, None) is None
-            else:
-                # Case 2b: Pure protobuf message or custom object with explicit presence.
-                try:
-                    should_populate = not request.HasField(field_name)
-                except (AttributeError, ValueError):
-                    # Fall back for objects/mocks that do not implement `HasField` or where `HasField` fails.
-                    should_populate = getattr(request, field_name, None) is None
+            # Extract the protobuf from proto-plus if wrapped.
+            pure_pb: google.protobuf.message.Message = getattr(request, "_pb", request)
+            try:
+                should_populate = not pure_pb.HasField(field_name)
+            except (AttributeError, ValueError):
+                # Fall back if `HasField` fails or is unsupported.
+                should_populate = getattr(pure_pb, field_name, None) is None
         else:
-            # Case 2c: Object request without explicit presence (`is_proto3_optional=False`).
+            # Case 2b: Object request without explicit presence (`is_proto3_optional=False`).
             # Auto-populate if the field value is falsy (None or empty string '').
-            should_populate = not getattr(request, field_name, None)
+            should_populate = not bool(getattr(request, field_name, False))
 
-    # Consolidate mutation to a single, clean DRY block.
+    # If the field was found to be empty, set random id
     if should_populate:
         generated_id = str(uuid.uuid4())
         if isinstance(request, dict):
diff --git a/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/tests/unit/gapic/storagebatchoperations_v1/test_compat.py b/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/tests/unit/gapic/storagebatchoperations_v1/test_compat.py
index 339e328027fd..4a3854581747 100755
--- a/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/tests/unit/gapic/storagebatchoperations_v1/test_compat.py
+++ b/packages/gapic-generator/tests/integration/goldens/storagebatchoperations/tests/unit/gapic/storagebatchoperations_v1/test_compat.py
@@ -247,9 +247,6 @@ def __init__(self, **kwargs):
         for k, v in kwargs.items():
             setattr(self, k, v)
 
-    def __contains__(self, key):
-        return hasattr(self, key)
-
 
 class MockProtoRequest:
     def __init__(self, **kwargs):
@@ -266,17 +263,11 @@ def __init__(self, **kwargs):
         for k, v in kwargs.items():
             setattr(self, k, v)
 
-    def __contains__(self, key):
-        return hasattr(self, key)
-
 
 class MockValueErrorRequest:
     def HasField(self, key):
         raise ValueError("Mismatched field")
 
-    def __contains__(self, key):
-        return hasattr(self, key)
-
 
 class MockProtoPlusValueErrorRequest:
     def __init__(self, **kwargs):
@@ -284,9 +275,6 @@ def __init__(self, **kwargs):
         for k, v in kwargs.items():
             setattr(self, k, v)
 
-    def __contains__(self, key):
-        return hasattr(self, key)
-
 UUID_REGEX = r"[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}"
 
 @pytest.mark.parametrize(
diff --git a/packages/google-api-core/google/api_core/gapic_v1/requests.py b/packages/google-api-core/google/api_core/gapic_v1/requests.py
index eedabfa56842..3dd0316bdf1e 100644
--- a/packages/google-api-core/google/api_core/gapic_v1/requests.py
+++ b/packages/google-api-core/google/api_core/gapic_v1/requests.py
@@ -76,33 +76,21 @@ def setup_request_id(
             # Auto-populate if the key is missing, None, or falsy (e.g., empty string '').
             should_populate = not request.get(field_name)
     else:
-        # Case 2: Object request (proto-plus wrapper, pure protobuf message, or mock/dict-like object).
-        pb_msg = getattr(request, "_pb", None)
-        is_proto_plus = pb_msg is not None and hasattr(pb_msg, "HasField")
+        # Case 2: Object request (proto-plus wrapper or pure protobuf message).
         if is_proto3_optional:
-            if is_proto_plus and pb_msg is not None:
-                # Case 2a: Proto-plus message with explicit presence.
-                # `proto.Message` instances wrap an underlying C++/Python protobuf message in `._pb`.
-                # We check `pb_msg.HasField(field_name)` to determine if the field was set by the user.
-                try:
-                    should_populate = not pb_msg.HasField(field_name)
-                except ValueError:
-                    # `HasField` raises ValueError if the field does not support presence (e.g., non-optional field).
-                    # Fall back to checking if the attribute value is explicitly None.
-                    should_populate = getattr(request, field_name, None) is None
-            else:
-                # Case 2b: Pure protobuf message or custom object with explicit presence.
-                try:
-                    should_populate = not request.HasField(field_name)
-                except (AttributeError, ValueError):
-                    # Fall back for objects/mocks that do not implement `HasField` or where `HasField` fails.
-                    should_populate = getattr(request, field_name, None) is None
+            # Extract the protobuf from proto-plus if wrapped.
+            pure_pb: google.protobuf.message.Message = getattr(request, "_pb", request)
+            try:
+                should_populate = not pure_pb.HasField(field_name)
+            except (AttributeError, ValueError):
+                # Fall back if `HasField` fails or is unsupported.
+                should_populate = getattr(pure_pb, field_name, None) is None
         else:
-            # Case 2c: Object request without explicit presence (`is_proto3_optional=False`).
+            # Case 2b: Object request without explicit presence (`is_proto3_optional=False`).
             # Auto-populate if the field value is falsy (None or empty string '').
-            should_populate = not getattr(request, field_name, None)
+            should_populate = not bool(getattr(request, field_name, False))
 
-    # Consolidate mutation to a single, clean DRY block.
+    # If the field was found to be empty, set random id
     if should_populate:
         generated_id = str(uuid.uuid4())
         if isinstance(request, dict):

From 9a526824487af77ba7b0886cd9779a94f95d70c8 Mon Sep 17 00:00:00 2001
From: Heba Alazzeh <hebaalazzeh@google.com>
Date: Thu, 6 Aug 2026 00:04:48 +0000
Subject: [PATCH 7/7] update comments

---
 .../google-api-core/google/api_core/gapic_v1/requests.py     | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/packages/google-api-core/google/api_core/gapic_v1/requests.py b/packages/google-api-core/google/api_core/gapic_v1/requests.py
index 3dd0316bdf1e..876f40aaa7b4 100644
--- a/packages/google-api-core/google/api_core/gapic_v1/requests.py
+++ b/packages/google-api-core/google/api_core/gapic_v1/requests.py
@@ -76,8 +76,9 @@ def setup_request_id(
             # Auto-populate if the key is missing, None, or falsy (e.g., empty string '').
             should_populate = not request.get(field_name)
     else:
-        # Case 2: Object request (proto-plus wrapper or pure protobuf message).
         if is_proto3_optional:
+            # Case 2a: Proto request with explicit presence (`is_proto3_optional=True`)
+            # (proto-plus wrapper or pure protobuf message).
             # Extract the protobuf from proto-plus if wrapped.
             pure_pb: google.protobuf.message.Message = getattr(request, "_pb", request)
             try:
@@ -86,7 +87,7 @@ def setup_request_id(
                 # Fall back if `HasField` fails or is unsupported.
                 should_populate = getattr(pure_pb, field_name, None) is None
         else:
-            # Case 2b: Object request without explicit presence (`is_proto3_optional=False`).
+            # Case 2b: Proto request without explicit presence (`is_proto3_optional=False`).
             # Auto-populate if the field value is falsy (None or empty string '').
             should_populate = not bool(getattr(request, field_name, False))