From 0ebbe414bf3beb3c9224a6b28dbdbe3df509f6ae Mon Sep 17 00:00:00 2001
From: Anthonios Partheniou <partheniou@google.com>
Date: Tue, 7 Mar 2023 11:34:37 +0000
Subject: [PATCH 01/14] fix: remove trailing underscore in transcoding

---
 google/api_core/path_template.py | 17 ++++++++++++++++-
 tests/unit/test_path_template.py |  7 +++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/google/api_core/path_template.py b/google/api_core/path_template.py
index b8ebb2af..c8933acd 100644
--- a/google/api_core/path_template.py
+++ b/google/api_core/path_template.py
@@ -308,9 +308,24 @@ def transcode(http_options, message=None, **request_kwargs):
             else:
                 try:
                     if message:
-                        request["body"] = getattr(leftovers, body)
+                        try:
+                            request["body"] = getattr(leftovers, body)
+                        except AttributeError as e:
+                            # gapic-generator-python appends underscores to field names
+                            # that collide with python keywords.
+                            # `_` is stripped away as it is not possible to
+                            # natively define a field with a trailing underscore in protobuf.
+                            # See related issue
+                            # https://github.com/googleapis/python-api-core/issues/227
+                            if hasattr(leftovers, body + "_"):
+                                request["body"] = getattr(leftovers, body + "_")
+                            else:
+                                raise e
                         delete_field(leftovers, body)
                     else:
+                        # gapic-generator-python appends underscores to field names
+                        # that collide with python keywords.
+                        leftovers = {key.rstrip('_') : val for key, val in leftovers.items()}
                         request["body"] = leftovers.pop(body)
                 except (KeyError, AttributeError):
                     continue
diff --git a/tests/unit/test_path_template.py b/tests/unit/test_path_template.py
index 808b36f3..431f0463 100644
--- a/tests/unit/test_path_template.py
+++ b/tests/unit/test_path_template.py
@@ -413,6 +413,13 @@ def test_transcode_with_wildcard(
             {"data": {"id": 1, "info": "some info"}, "foo": "bar"},
             ["post", "/v1/no/template", {"id": 1, "info": "some info"}, {"foo": "bar"}],
         ],
+        # Single field body with trailing underscore
+        [
+            [["post", "/v1/no/template", "data"]],
+            None,
+            {"data": {"id": 1, "info": "some info"}, "foo_": "bar"},
+            ["post", "/v1/no/template", {"id": 1, "info": "some info"}, {"foo": "bar"}],
+        ],
         [
             [["post", "/v1/no/template", "oauth"]],
             auth_pb2.AuthenticationRule(

From 262c60e2f440d2e9809a1d324e1a098bf32d36b3 Mon Sep 17 00:00:00 2001
From: Anthonios Partheniou <partheniou@google.com>
Date: Tue, 7 Mar 2023 11:50:25 +0000
Subject: [PATCH 02/14] lint

---
 google/api_core/path_template.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/google/api_core/path_template.py b/google/api_core/path_template.py
index c8933acd..80c98cc2 100644
--- a/google/api_core/path_template.py
+++ b/google/api_core/path_template.py
@@ -325,7 +325,9 @@ def transcode(http_options, message=None, **request_kwargs):
                     else:
                         # gapic-generator-python appends underscores to field names
                         # that collide with python keywords.
-                        leftovers = {key.rstrip('_') : val for key, val in leftovers.items()}
+                        leftovers = {
+                            key.rstrip("_"): val for key, val in leftovers.items()
+                        }
                         request["body"] = leftovers.pop(body)
                 except (KeyError, AttributeError):
                     continue

From f192273d2f9c483104016a84b096bc9a5bd74921 Mon Sep 17 00:00:00 2001
From: Anthonios Partheniou <partheniou@google.com>
Date: Tue, 7 Mar 2023 11:51:04 +0000
Subject: [PATCH 03/14] add test

---
 tests/unit/test_path_template.py | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/tests/unit/test_path_template.py b/tests/unit/test_path_template.py
index 431f0463..881ea15b 100644
--- a/tests/unit/test_path_template.py
+++ b/tests/unit/test_path_template.py
@@ -626,6 +626,14 @@ def test_transcode_with_additional_bindings(
             auth_pb2.AuthenticationRule(selector="first"),
             {},
         ],
+        # Test trailing underscore in body is removed during transcoding
+        # See https://github.com/googleapis/python-api-core/issues/490
+        [[["post", "/v1/{name}", "data"]], None, {"name": "first/last"}],
+        [
+            [["post", "/v1/{selector}", "data_"]],
+            auth_pb2.AuthenticationRule(selector="first"),
+            {},
+        ],
         [[["post", "/v1/{first_name}", "data"]], None, {"last_name": "last"}],
         [
             [["post", "/v1/{first_name}", ""]],

From 3ba7c348bf39c26e2412636240c52195b8e1ff95 Mon Sep 17 00:00:00 2001
From: Anthonios Partheniou <partheniou@google.com>
Date: Tue, 7 Mar 2023 12:23:30 +0000
Subject: [PATCH 04/14] revert test

---
 tests/unit/test_path_template.py | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/tests/unit/test_path_template.py b/tests/unit/test_path_template.py
index 881ea15b..431f0463 100644
--- a/tests/unit/test_path_template.py
+++ b/tests/unit/test_path_template.py
@@ -626,14 +626,6 @@ def test_transcode_with_additional_bindings(
             auth_pb2.AuthenticationRule(selector="first"),
             {},
         ],
-        # Test trailing underscore in body is removed during transcoding
-        # See https://github.com/googleapis/python-api-core/issues/490
-        [[["post", "/v1/{name}", "data"]], None, {"name": "first/last"}],
-        [
-            [["post", "/v1/{selector}", "data_"]],
-            auth_pb2.AuthenticationRule(selector="first"),
-            {},
-        ],
         [[["post", "/v1/{first_name}", "data"]], None, {"last_name": "last"}],
         [
             [["post", "/v1/{first_name}", ""]],

From 71810fd5ea71baf887cde9fcf0923c416d387605 Mon Sep 17 00:00:00 2001
From: Anthonios Partheniou <partheniou@google.com>
Date: Tue, 7 Mar 2023 15:53:49 +0000
Subject: [PATCH 05/14] add test

---
 google/api_core/path_template.py |  3 ++-
 tests/unit/test_path_template.py | 17 +++++++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/google/api_core/path_template.py b/google/api_core/path_template.py
index 80c98cc2..ac54e365 100644
--- a/google/api_core/path_template.py
+++ b/google/api_core/path_template.py
@@ -310,6 +310,7 @@ def transcode(http_options, message=None, **request_kwargs):
                     if message:
                         try:
                             request["body"] = getattr(leftovers, body)
+                            delete_field(leftovers, body)
                         except AttributeError as e:
                             # gapic-generator-python appends underscores to field names
                             # that collide with python keywords.
@@ -319,9 +320,9 @@ def transcode(http_options, message=None, **request_kwargs):
                             # https://github.com/googleapis/python-api-core/issues/227
                             if hasattr(leftovers, body + "_"):
                                 request["body"] = getattr(leftovers, body + "_")
+                                delete_field(leftovers, body + "_")
                             else:
                                 raise e
-                        delete_field(leftovers, body)
                     else:
                         # gapic-generator-python appends underscores to field names
                         # that collide with python keywords.
diff --git a/tests/unit/test_path_template.py b/tests/unit/test_path_template.py
index 431f0463..0b93f4d6 100644
--- a/tests/unit/test_path_template.py
+++ b/tests/unit/test_path_template.py
@@ -17,10 +17,20 @@
 import mock
 import pytest
 
+import proto
+
 from google.api import auth_pb2
 from google.api_core import path_template
 
 
+class Breakpoint(proto.Message):
+    name = proto.Field(proto.STRING, number=1)
+
+class SomeMessage(proto.Message):
+    breakpoint_ = proto.Field(Breakpoint, number=1)
+    debuggee_id = proto.Field(proto.STRING, number=2)
+
+
 @pytest.mark.parametrize(
     "tmpl, args, kwargs, expected_result",
     [
@@ -420,6 +430,13 @@ def test_transcode_with_wildcard(
             {"data": {"id": 1, "info": "some info"}, "foo_": "bar"},
             ["post", "/v1/no/template", {"id": 1, "info": "some info"}, {"foo": "bar"}],
         ],
+        # Single field body with reserved keyword, using message where field name has trailing underscore
+        [
+            [["post", "/v1/no/template", "breakpoint"]],
+            SomeMessage(breakpoint_=Breakpoint(name="test"),debuggee_id="test")._pb,
+            {},
+            ["post", "/v1/no/template", Breakpoint(name="test")._pb, SomeMessage(debuggee_id="test")._pb],
+        ],
         [
             [["post", "/v1/no/template", "oauth"]],
             auth_pb2.AuthenticationRule(

From 9d730851a876f8019c4ea4a76921e19b8dce1771 Mon Sep 17 00:00:00 2001
From: Anthonios Partheniou <partheniou@google.com>
Date: Tue, 7 Mar 2023 15:56:50 +0000
Subject: [PATCH 06/14] lint

---
 tests/unit/test_path_template.py | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/tests/unit/test_path_template.py b/tests/unit/test_path_template.py
index 0b93f4d6..edbe9ed5 100644
--- a/tests/unit/test_path_template.py
+++ b/tests/unit/test_path_template.py
@@ -26,6 +26,7 @@
 class Breakpoint(proto.Message):
     name = proto.Field(proto.STRING, number=1)
 
+
 class SomeMessage(proto.Message):
     breakpoint_ = proto.Field(Breakpoint, number=1)
     debuggee_id = proto.Field(proto.STRING, number=2)
@@ -433,9 +434,14 @@ def test_transcode_with_wildcard(
         # Single field body with reserved keyword, using message where field name has trailing underscore
         [
             [["post", "/v1/no/template", "breakpoint"]],
-            SomeMessage(breakpoint_=Breakpoint(name="test"),debuggee_id="test")._pb,
+            SomeMessage(breakpoint_=Breakpoint(name="test"), debuggee_id="test")._pb,
             {},
-            ["post", "/v1/no/template", Breakpoint(name="test")._pb, SomeMessage(debuggee_id="test")._pb],
+            [
+                "post",
+                "/v1/no/template",
+                Breakpoint(name="test")._pb,
+                SomeMessage(debuggee_id="test")._pb,
+            ],
         ],
         [
             [["post", "/v1/no/template", "oauth"]],

From e3778923771a9f7568bd716b467c68c4effd41fc Mon Sep 17 00:00:00 2001
From: Anthonios Partheniou <partheniou@google.com>
Date: Wed, 8 Mar 2023 10:31:56 +0000
Subject: [PATCH 07/14] Address review comments

---
 google/api_core/path_template.py | 38 ++++++++++++++++----------------
 tests/unit/test_path_template.py |  9 +++++---
 2 files changed, 25 insertions(+), 22 deletions(-)

diff --git a/google/api_core/path_template.py b/google/api_core/path_template.py
index ac54e365..ec795688 100644
--- a/google/api_core/path_template.py
+++ b/google/api_core/path_template.py
@@ -298,6 +298,15 @@ def transcode(http_options, message=None, **request_kwargs):
         # Assign body and query params
         body = http_option.get("body")
 
+        # gapic-generator-python appends underscores to field names
+        # that collide with python keywords.
+        # `_` is stripped away as it is not possible to
+        # natively define a field with a trailing underscore in protobuf.
+        # See related issue
+        # https://github.com/googleapis/python-api-core/issues/227
+        if isinstance(leftovers, dict):
+            leftovers = {key.rstrip("_"): val for key, val in leftovers.items()}
+
         if body:
             if body == "*":
                 request["body"] = leftovers
@@ -308,27 +317,18 @@ def transcode(http_options, message=None, **request_kwargs):
             else:
                 try:
                     if message:
-                        try:
-                            request["body"] = getattr(leftovers, body)
-                            delete_field(leftovers, body)
-                        except AttributeError as e:
-                            # gapic-generator-python appends underscores to field names
-                            # that collide with python keywords.
-                            # `_` is stripped away as it is not possible to
-                            # natively define a field with a trailing underscore in protobuf.
-                            # See related issue
-                            # https://github.com/googleapis/python-api-core/issues/227
-                            if hasattr(leftovers, body + "_"):
-                                request["body"] = getattr(leftovers, body + "_")
-                                delete_field(leftovers, body + "_")
-                            else:
-                                raise e
-                    else:
                         # gapic-generator-python appends underscores to field names
                         # that collide with python keywords.
-                        leftovers = {
-                            key.rstrip("_"): val for key, val in leftovers.items()
-                        }
+                        # `_` is stripped away as it is not possible to
+                        # natively define a field with a trailing underscore in protobuf.
+                        # See related issue
+                        # https://github.com/googleapis/python-api-core/issues/227
+                        field_suffix = ""
+                        if hasattr(leftovers, body + "_"):
+                            field_suffix = "_"
+                        request["body"] = getattr(leftovers, f"{body}{field_suffix}")
+                        delete_field(leftovers, f"{body}{field_suffix}")
+                    else:
                         request["body"] = leftovers.pop(body)
                 except (KeyError, AttributeError):
                     continue
diff --git a/tests/unit/test_path_template.py b/tests/unit/test_path_template.py
index edbe9ed5..148e2936 100644
--- a/tests/unit/test_path_template.py
+++ b/tests/unit/test_path_template.py
@@ -30,6 +30,7 @@ class Breakpoint(proto.Message):
 class SomeMessage(proto.Message):
     breakpoint_ = proto.Field(Breakpoint, number=1)
     debuggee_id = proto.Field(proto.STRING, number=2)
+    stacktrace_ = proto.Field(proto.STRING, number=3)
 
 
 @pytest.mark.parametrize(
@@ -434,13 +435,15 @@ def test_transcode_with_wildcard(
         # Single field body with reserved keyword, using message where field name has trailing underscore
         [
             [["post", "/v1/no/template", "breakpoint"]],
-            SomeMessage(breakpoint_=Breakpoint(name="test"), debuggee_id="test")._pb,
+            SomeMessage(
+                breakpoint_=Breakpoint(name="foo"), debuggee_id="bar", stacktrace_="baz"
+            )._pb,
             {},
             [
                 "post",
                 "/v1/no/template",
-                Breakpoint(name="test")._pb,
-                SomeMessage(debuggee_id="test")._pb,
+                Breakpoint(name="foo")._pb,
+                SomeMessage(debuggee_id="bar", stacktrace_="baz")._pb,
             ],
         ],
         [

From 1c568945277c464ef2a77643470135365d0c083b Mon Sep 17 00:00:00 2001
From: Anthonios Partheniou <partheniou@google.com>
Date: Wed, 8 Mar 2023 10:36:46 +0000
Subject: [PATCH 08/14] clarify comment

---
 google/api_core/path_template.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/google/api_core/path_template.py b/google/api_core/path_template.py
index ec795688..9da29563 100644
--- a/google/api_core/path_template.py
+++ b/google/api_core/path_template.py
@@ -298,7 +298,7 @@ def transcode(http_options, message=None, **request_kwargs):
         # Assign body and query params
         body = http_option.get("body")
 
-        # gapic-generator-python appends underscores to field names
+        # gapic-generator-python appends an underscore to field names
         # that collide with python keywords.
         # `_` is stripped away as it is not possible to
         # natively define a field with a trailing underscore in protobuf.
@@ -317,7 +317,7 @@ def transcode(http_options, message=None, **request_kwargs):
             else:
                 try:
                     if message:
-                        # gapic-generator-python appends underscores to field names
+                        # gapic-generator-python append an underscores to field names
                         # that collide with python keywords.
                         # `_` is stripped away as it is not possible to
                         # natively define a field with a trailing underscore in protobuf.

From eb3b50e105987d6942098aa1670a896aeadb2e50 Mon Sep 17 00:00:00 2001
From: Anthonios Partheniou <partheniou@google.com>
Date: Thu, 9 Mar 2023 16:16:55 +0000
Subject: [PATCH 09/14] address review feedback

---
 google/api_core/path_template.py | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/google/api_core/path_template.py b/google/api_core/path_template.py
index 9da29563..6a260ebf 100644
--- a/google/api_core/path_template.py
+++ b/google/api_core/path_template.py
@@ -317,12 +317,10 @@ def transcode(http_options, message=None, **request_kwargs):
             else:
                 try:
                     if message:
-                        # gapic-generator-python append an underscores to field names
-                        # that collide with python keywords.
-                        # `_` is stripped away as it is not possible to
-                        # natively define a field with a trailing underscore in protobuf.
-                        # See related issue
-                        # https://github.com/googleapis/python-api-core/issues/227
+                        # See above comment where gapic-generator-python appends
+                        # underscores to field names that are python reserved words
+                        # If the message has an attribute with an underscore suffix, 
+                        # use that instead.
                         field_suffix = ""
                         if hasattr(leftovers, body + "_"):
                             field_suffix = "_"

From 3e2834c88bf1145edc0c9368e56736ffc8370dc1 Mon Sep 17 00:00:00 2001
From: Anthonios Partheniou <partheniou@google.com>
Date: Thu, 9 Mar 2023 16:17:24 +0000
Subject: [PATCH 10/14] typo

---
 google/api_core/path_template.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/google/api_core/path_template.py b/google/api_core/path_template.py
index 6a260ebf..cfa8cc31 100644
--- a/google/api_core/path_template.py
+++ b/google/api_core/path_template.py
@@ -318,7 +318,7 @@ def transcode(http_options, message=None, **request_kwargs):
                 try:
                     if message:
                         # See above comment where gapic-generator-python appends
-                        # underscores to field names that are python reserved words
+                        # underscores to field names that are python reserved words.
                         # If the message has an attribute with an underscore suffix, 
                         # use that instead.
                         field_suffix = ""

From dd317a9b185330a6ee9f3226efdbab0cd3310d98 Mon Sep 17 00:00:00 2001
From: Anthonios Partheniou <partheniou@google.com>
Date: Thu, 9 Mar 2023 16:20:04 +0000
Subject: [PATCH 11/14] lint

---
 google/api_core/path_template.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/google/api_core/path_template.py b/google/api_core/path_template.py
index cfa8cc31..4edee03b 100644
--- a/google/api_core/path_template.py
+++ b/google/api_core/path_template.py
@@ -319,7 +319,7 @@ def transcode(http_options, message=None, **request_kwargs):
                     if message:
                         # See above comment where gapic-generator-python appends
                         # underscores to field names that are python reserved words.
-                        # If the message has an attribute with an underscore suffix, 
+                        # If the message has an attribute with an underscore suffix,
                         # use that instead.
                         field_suffix = ""
                         if hasattr(leftovers, body + "_"):

From 0918c7a8a8d3ff711923de1bdab3036260c0a826 Mon Sep 17 00:00:00 2001
From: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>
Date: Thu, 9 Mar 2023 16:21:05 +0000
Subject: [PATCH 12/14] =?UTF-8?q?=F0=9F=A6=89=20Updates=20from=20OwlBot=20?=
 =?UTF-8?q?post-processor?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md
---
 google/api_core/path_template.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/google/api_core/path_template.py b/google/api_core/path_template.py
index cfa8cc31..4edee03b 100644
--- a/google/api_core/path_template.py
+++ b/google/api_core/path_template.py
@@ -319,7 +319,7 @@ def transcode(http_options, message=None, **request_kwargs):
                     if message:
                         # See above comment where gapic-generator-python appends
                         # underscores to field names that are python reserved words.
-                        # If the message has an attribute with an underscore suffix, 
+                        # If the message has an attribute with an underscore suffix,
                         # use that instead.
                         field_suffix = ""
                         if hasattr(leftovers, body + "_"):

From 5504d0ad2112f328d42af3eba5ed3a0a98c2a292 Mon Sep 17 00:00:00 2001
From: Anthonios Partheniou <partheniou@google.com>
Date: Tue, 14 Mar 2023 13:47:56 +0000
Subject: [PATCH 13/14] address review feedback

---
 google/api_core/path_template.py | 24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/google/api_core/path_template.py b/google/api_core/path_template.py
index 4edee03b..1108bedb 100644
--- a/google/api_core/path_template.py
+++ b/google/api_core/path_template.py
@@ -299,13 +299,22 @@ def transcode(http_options, message=None, **request_kwargs):
         body = http_option.get("body")
 
         # gapic-generator-python appends an underscore to field names
-        # that collide with python keywords.
-        # `_` is stripped away as it is not possible to
-        # natively define a field with a trailing underscore in protobuf.
-        # See related issue
+        # that collide with python keywords. See related issue
         # https://github.com/googleapis/python-api-core/issues/227
+        # `leftovers` can either be a dict or protobuf message.
+        # When `leftovers` is a dict, the `_` suffix in each key
+        # is stripped away as it is not possible to natively define a field
+        # with a trailing underscore in protobuf.
+        # When `leftovers` is a protobuf message, we need to use an underscore
+        # suffix when accessing the field in the protobuf message when the
+        # field has an underscore suffix.
+        field_suffix = ""
+
         if isinstance(leftovers, dict):
             leftovers = {key.rstrip("_"): val for key, val in leftovers.items()}
+        elif body:
+            if hasattr(leftovers, body + "_"):
+                field_suffix = "_"
 
         if body:
             if body == "*":
@@ -317,13 +326,6 @@ def transcode(http_options, message=None, **request_kwargs):
             else:
                 try:
                     if message:
-                        # See above comment where gapic-generator-python appends
-                        # underscores to field names that are python reserved words.
-                        # If the message has an attribute with an underscore suffix,
-                        # use that instead.
-                        field_suffix = ""
-                        if hasattr(leftovers, body + "_"):
-                            field_suffix = "_"
                         request["body"] = getattr(leftovers, f"{body}{field_suffix}")
                         delete_field(leftovers, f"{body}{field_suffix}")
                     else:

From 6558cc66b0082f67ba70cc1c96491d1d79d4ef1b Mon Sep 17 00:00:00 2001
From: Anthonios Partheniou <partheniou@google.com>
Date: Tue, 14 Mar 2023 14:35:36 +0000
Subject: [PATCH 14/14] clarify comment

---
 google/api_core/path_template.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/google/api_core/path_template.py b/google/api_core/path_template.py
index 1108bedb..2b90a710 100644
--- a/google/api_core/path_template.py
+++ b/google/api_core/path_template.py
@@ -301,6 +301,8 @@ def transcode(http_options, message=None, **request_kwargs):
         # gapic-generator-python appends an underscore to field names
         # that collide with python keywords. See related issue
         # https://github.com/googleapis/python-api-core/issues/227
+        # Make sure that when the fields are REST encoded, the
+        # Python-specific trailing underscore is removed before going on the wire.
         # `leftovers` can either be a dict or protobuf message.
         # When `leftovers` is a dict, the `_` suffix in each key
         # is stripped away as it is not possible to natively define a field