From 2ea6ec75a015257b592c3f2f5974600e8216489b Mon Sep 17 00:00:00 2001
From: Vaibhav Pratap <vaibhavpratap85@gmail.com>
Date: Wed, 15 Jul 2026 08:48:36 +0000
Subject: [PATCH 01/12] feat(storage): migrate async client to unified checksum
 options

---
 .../storage/google_cloud_cpp_storage_grpc.bzl |   1 +
 .../google_cloud_cpp_storage_grpc.cmake       |   1 +
 .../storage/internal/async/checksum_helpers.h |  49 ++++++++
 .../storage/internal/async/connection_impl.cc |  42 ++++---
 .../async/connection_impl_read_hash_test.cc   | 108 +++++++++++-------
 .../async/connection_impl_upload_hash_test.cc |  53 ++++++---
 .../internal/async/default_options_test.cc    |  11 ++
 .../internal/async/object_descriptor_impl.cc  |  12 +-
 .../async/object_descriptor_impl_test.cc      |  11 ++
 .../internal/async/writer_connection_impl.cc  |  20 ++--
 .../tests/async_client_integration_test.cc    |  17 +--
 11 files changed, 232 insertions(+), 93 deletions(-)
 create mode 100644 google/cloud/storage/internal/async/checksum_helpers.h

diff --git a/google/cloud/storage/google_cloud_cpp_storage_grpc.bzl b/google/cloud/storage/google_cloud_cpp_storage_grpc.bzl
index 4113b1e4cab04..6c1ad25a15247 100644
--- a/google/cloud/storage/google_cloud_cpp_storage_grpc.bzl
+++ b/google/cloud/storage/google_cloud_cpp_storage_grpc.bzl
@@ -38,6 +38,7 @@ google_cloud_cpp_storage_grpc_hdrs = [
     "async/writer_connection.h",
     "grpc_plugin.h",
     "internal/async/connection_fwd.h",
+    "internal/async/checksum_helpers.h",
     "internal/async/connection_impl.h",
     "internal/async/connection_tracing.h",
     "internal/async/default_options.h",
diff --git a/google/cloud/storage/google_cloud_cpp_storage_grpc.cmake b/google/cloud/storage/google_cloud_cpp_storage_grpc.cmake
index e9b81bf9526be..952d6dbef46d2 100644
--- a/google/cloud/storage/google_cloud_cpp_storage_grpc.cmake
+++ b/google/cloud/storage/google_cloud_cpp_storage_grpc.cmake
@@ -99,6 +99,7 @@ add_library(
     async/writer_connection.h
     grpc_plugin.cc
     grpc_plugin.h
+    internal/async/checksum_helpers.h
     internal/async/connection_fwd.h
     internal/async/connection_impl.cc
     internal/async/connection_impl.h
diff --git a/google/cloud/storage/internal/async/checksum_helpers.h b/google/cloud/storage/internal/async/checksum_helpers.h
new file mode 100644
index 0000000000000..eb8bd14cc3bfa
--- /dev/null
+++ b/google/cloud/storage/internal/async/checksum_helpers.h
@@ -0,0 +1,49 @@
+// Copyright 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef GOOGLE_CLOUD_CPP_GOOGLE_CLOUD_STORAGE_INTERNAL_ASYNC_CHECKSUM_HELPERS_H
+#define GOOGLE_CLOUD_CPP_GOOGLE_CLOUD_STORAGE_INTERNAL_ASYNC_CHECKSUM_HELPERS_H
+
+#include "google/cloud/internal/disable_deprecation_warnings.inc"
+#include "google/cloud/storage/async/options.h"
+#include "google/cloud/storage/options.h"
+#include "google/cloud/options.h"
+
+namespace google {
+namespace cloud {
+namespace storage_internal {
+GOOGLE_CLOUD_CPP_INLINE_NAMESPACE_BEGIN
+
+struct ChecksumSettings {
+  bool enable_crc32c;
+  bool enable_md5;
+};
+
+inline ChecksumSettings GetDownloadChecksumSettings(Options const& options) {
+  if (options.has<storage::DownloadChecksumValidationOption>()) {
+    auto const algo = options.get<storage::DownloadChecksumValidationOption>();
+    return {algo == storage::ChecksumAlgorithm::kCrc32c,
+            algo == storage::ChecksumAlgorithm::kMD5};
+  }
+  return {options.get<storage::EnableCrc32cValidationOption>(),
+          options.get<storage::EnableMD5ValidationOption>()};
+}
+
+GOOGLE_CLOUD_CPP_INLINE_NAMESPACE_END
+}  // namespace storage_internal
+}  // namespace cloud
+}  // namespace google
+
+#include "google/cloud/internal/diagnostics_pop.inc"
+#endif  // GOOGLE_CLOUD_CPP_GOOGLE_CLOUD_STORAGE_INTERNAL_ASYNC_CHECKSUM_HELPERS_H
diff --git a/google/cloud/storage/internal/async/connection_impl.cc b/google/cloud/storage/internal/async/connection_impl.cc
index b1622bd87a386..60e6d77879407 100644
--- a/google/cloud/storage/internal/async/connection_impl.cc
+++ b/google/cloud/storage/internal/async/connection_impl.cc
@@ -19,6 +19,7 @@
 #include "google/cloud/storage/async/reader.h"
 #include "google/cloud/storage/async/resume_policy.h"
 #include "google/cloud/storage/async/retry_policy.h"
+#include "google/cloud/storage/internal/async/checksum_helpers.h"
 #include "google/cloud/storage/internal/async/default_options.h"
 #include "google/cloud/storage/internal/async/handle_redirect_error.h"
 #include "google/cloud/storage/internal/async/insert_object.h"
@@ -82,12 +83,24 @@ inline std::unique_ptr<storage::AsyncIdempotencyPolicy> idempotency_policy(
 std::unique_ptr<storage::internal::HashFunction> CreateHashFunction(
     Options const& options) {
   auto crc32c = std::unique_ptr<storage::internal::HashFunction>();
+  bool enable_crc32c = false;
+  bool enable_md5 = false;
+
+  if (options.has<storage::UploadChecksumValidationOption>()) {
+    auto const algo = options.get<storage::UploadChecksumValidationOption>();
+    enable_crc32c = (algo == storage::ChecksumAlgorithm::kCrc32c);
+    enable_md5 = (algo == storage::ChecksumAlgorithm::kMD5);
+  } else {
+    enable_crc32c = options.get<storage::EnableCrc32cValidationOption>();
+    enable_md5 = options.get<storage::EnableMD5ValidationOption>();
+  }
+
   if (options.has<storage::UseCrc32cValueOption>()) {
     crc32c = std::make_unique<storage::internal::PrecomputedHashFunction>(
         storage::internal::HashValues{
             Crc32cFromProto(options.get<storage::UseCrc32cValueOption>()),
             /*.md5=*/{}});
-  } else if (options.get<storage::EnableCrc32cValidationOption>()) {
+  } else if (enable_crc32c) {
     crc32c = std::make_unique<storage::internal::Crc32cHashFunction>();
   }
 
@@ -97,7 +110,7 @@ std::unique_ptr<storage::internal::HashFunction> CreateHashFunction(
         storage::internal::HashValues{
             /*.crc32=*/{},
             MD5FromProto(options.get<storage::UseMD5ValueOption>())});
-  } else if (options.get<storage::EnableMD5ValidationOption>()) {
+  } else if (enable_md5) {
     md5 = storage::internal::MD5HashFunction::Create();
   }
 
@@ -117,9 +130,7 @@ std::unique_ptr<storage::internal::HashValidator> CreateHashValidator(
       request.read_limit() != 0 || request.read_offset() != 0;
   if (is_ranged_read) return storage::internal::CreateNullHashValidator();
 
-  auto const enable_crc32c =
-      options.get<storage::EnableCrc32cValidationOption>();
-  auto const enable_md5 = options.get<storage::EnableMD5ValidationOption>();
+  auto const [enable_crc32c, enable_md5] = GetDownloadChecksumSettings(options);
 
   if (enable_crc32c && enable_md5) {
     return std::make_unique<storage::internal::CompositeValidator>(
@@ -412,7 +423,7 @@ AsyncConnectionImpl::AppendableObjectUploadImpl(AppendableUploadParams p) {
   return pending.then(
       [current, request = std::move(p.request), hash = std::move(hash_function),
        fa = std::move(factory)](auto f) mutable
-      -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+          -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
         auto rpc = f.get();
         if (!rpc) return std::move(rpc).status();
         std::unique_ptr<AsyncWriterConnectionImpl> impl;
@@ -467,7 +478,7 @@ AsyncConnectionImpl::StartBufferedUpload(UploadParams p) {
   return StartUnbufferedUpload(std::move(p))
       .then([current = std::move(current),
              async_write_object = std::move(async_write_object)](auto f) mutable
-            -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+                -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
         auto w = f.get();
         if (!w) return std::move(w).status();
         auto factory = [upload_id = (*w)->UploadId(),
@@ -501,14 +512,15 @@ AsyncConnectionImpl::ResumeBufferedUpload(ResumeUploadParams p) {
   };
 
   auto f = make_unbuffered();
-  return f.then([current = std::move(current),
-                 make_unbuffered = std::move(make_unbuffered)](auto f) mutable
-                -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
-    auto w = f.get();
-    if (!w) return std::move(w).status();
-    return MakeWriterConnectionBuffered(std::move(make_unbuffered),
-                                        *std::move(w), *current);
-  });
+  return f.then(
+      [current = std::move(current),
+       make_unbuffered = std::move(make_unbuffered)](auto f) mutable
+          -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+        auto w = f.get();
+        if (!w) return std::move(w).status();
+        return MakeWriterConnectionBuffered(std::move(make_unbuffered),
+                                            *std::move(w), *current);
+      });
 }
 
 future<StatusOr<google::storage::v2::Object>>
diff --git a/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc b/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
index 4b2658d83eb73..2fbb3a2f6e6df 100644
--- a/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
+++ b/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
@@ -13,6 +13,17 @@
 // limitations under the License.
 
 #include "google/cloud/storage/async/options.h"
+
+// TODO: Remove this when EnableMD5ValidationOption and
+// EnableCrc32cValidationOption are removed.
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#endif
+
 #include "google/cloud/storage/internal/async/connection_impl.h"
 #include "google/cloud/storage/internal/async/default_options.h"
 #include "google/cloud/storage/internal/crc32c.h"
@@ -75,15 +86,21 @@ auto GeneratedObjectChecksums(HashTestCase const& tc) {
 std::ostream& operator<<(std::ostream& os, HashTestCase const& rhs) {
   os << "HashTestCase={options={";
   os << "expected_status_code=" << rhs.expected_status_code  //
-     << std::boolalpha                                       //
-     << ", enable_crc32c_validation="
-     << rhs.options.get<storage::EnableCrc32cValidationOption>();
+     << std::boolalpha;                                      //
+  if (rhs.options.has<storage::DownloadChecksumValidationOption>()) {
+    os << ", download_checksum="
+       << static_cast<int>(
+              rhs.options.get<storage::DownloadChecksumValidationOption>());
+  } else {
+    os << ", enable_crc32c_validation="
+       << rhs.options.get<storage::EnableCrc32cValidationOption>();
+    os << ", enable_md5_validation="
+       << rhs.options.get<storage::EnableMD5ValidationOption>();
+  }
   if (rhs.options.has<storage::UseCrc32cValueOption>()) {
     os << ", use_crc32_value="
        << rhs.options.get<storage::UseCrc32cValueOption>();
   }
-  os << ", enable_md5_validation="
-     << rhs.options.get<storage::EnableMD5ValidationOption>();
   if (rhs.options.has<storage::UseMD5ValueOption>()) {
     os << ", use_md5_value=" << rhs.options.get<storage::UseMD5ValueOption>();
   }
@@ -129,56 +146,67 @@ INSTANTIATE_TEST_SUITE_P(
             // This is the common case. Only CRC32C is enabled by default. The
             // service returns both CRC32C and MD5 values.
             StatusCode::kOk,
-            Options{}
-                .set<storage::EnableCrc32cValidationOption>(true)
-                .set<storage::EnableMD5ValidationOption>(false),
+            Options{}.set<storage::DownloadChecksumValidationOption>(
+                storage::ChecksumAlgorithm::kCrc32c),
             kQuickFoxCrc32cChecksum, kQuickFoxMD5Hash},
         HashTestCase{
             // This is also common, the service does not return a MD5 value.
             StatusCode::kOk,
-            Options{}
-                .set<storage::EnableCrc32cValidationOption>(true)
-                .set<storage::EnableMD5ValidationOption>(false),
+            Options{}.set<storage::DownloadChecksumValidationOption>(
+                storage::ChecksumAlgorithm::kCrc32c),
             kQuickFoxCrc32cChecksum, ""},
         // Make sure things work when both hashes are validated too.
         HashTestCase{StatusCode::kOk,
-                     Options{}
-                         .set<storage::EnableCrc32cValidationOption>(true)
-                         .set<storage::EnableMD5ValidationOption>(true),
+                     Options{}.set<storage::DownloadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kNone),
                      kQuickFoxCrc32cChecksum, kQuickFoxMD5Hash},
         // In the next three cases we verify that disabling some validation
         // works.
         HashTestCase{StatusCode::kOk,
-                     Options{}
-                         .set<storage::EnableCrc32cValidationOption>(true)
-                         .set<storage::EnableMD5ValidationOption>(false),
+                     Options{}.set<storage::DownloadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kCrc32c),
                      kQuickFoxCrc32cChecksum, kQuickFoxMD5HashBad},
         HashTestCase{StatusCode::kOk,
-                     Options{}
-                         .set<storage::EnableCrc32cValidationOption>(false)
-                         .set<storage::EnableMD5ValidationOption>(true),
+                     Options{}.set<storage::DownloadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kMD5),
                      kQuickFoxCrc32cChecksumBad, kQuickFoxMD5Hash},
         HashTestCase{StatusCode::kOk,
-                     Options{}
-                         .set<storage::EnableCrc32cValidationOption>(false)
-                         .set<storage::EnableMD5ValidationOption>(false),
+                     Options{}.set<storage::DownloadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kNone),
+                     kQuickFoxCrc32cChecksumBad, kQuickFoxMD5HashBad},
+        HashTestCase{StatusCode::kOk,
+                     Options{}.set<storage::DownloadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kCrc32c),
+                     kQuickFoxCrc32cChecksum, kQuickFoxMD5HashBad},
+        HashTestCase{StatusCode::kOk,
+                     Options{}.set<storage::DownloadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kMD5),
+                     kQuickFoxCrc32cChecksumBad, kQuickFoxMD5Hash},
+        HashTestCase{StatusCode::kOk,
+                     Options{}.set<storage::DownloadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kNone),
                      kQuickFoxCrc32cChecksumBad, kQuickFoxMD5HashBad},
         // In the next three cases we verify that validation works when the
         // returned values are not correct.
         HashTestCase{StatusCode::kInvalidArgument,
-                     Options{}
-                         .set<storage::EnableCrc32cValidationOption>(false)
-                         .set<storage::EnableMD5ValidationOption>(true),
+                     Options{}.set<storage::DownloadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kMD5),
+                     kQuickFoxCrc32cChecksumBad, kQuickFoxMD5HashBad},
+        HashTestCase{StatusCode::kInvalidArgument,
+                     Options{}.set<storage::DownloadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kCrc32c),
+                     kQuickFoxCrc32cChecksumBad, kQuickFoxMD5HashBad},
+        HashTestCase{StatusCode::kInvalidArgument,
+                     Options{}.set<storage::DownloadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kNone),
                      kQuickFoxCrc32cChecksumBad, kQuickFoxMD5HashBad},
         HashTestCase{StatusCode::kInvalidArgument,
-                     Options{}
-                         .set<storage::EnableCrc32cValidationOption>(true)
-                         .set<storage::EnableMD5ValidationOption>(false),
+                     Options{}.set<storage::DownloadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kCrc32c),
                      kQuickFoxCrc32cChecksumBad, kQuickFoxMD5HashBad},
         HashTestCase{StatusCode::kInvalidArgument,
-                     Options{}
-                         .set<storage::EnableCrc32cValidationOption>(true)
-                         .set<storage::EnableMD5ValidationOption>(true),
+                     Options{}.set<storage::DownloadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kMD5),
                      kQuickFoxCrc32cChecksumBad, kQuickFoxMD5HashBad},
         // The application may know what the values should be. Verify the
         // validation works correctly when the application provides correct
@@ -186,8 +214,8 @@ INSTANTIATE_TEST_SUITE_P(
         HashTestCase{
             StatusCode::kOk,
             Options{}
-                .set<storage::EnableCrc32cValidationOption>(true)
-                .set<storage::EnableMD5ValidationOption>(true)
+                .set<storage::DownloadChecksumValidationOption>(
+                    storage::ChecksumAlgorithm::kCrc32c)
                 .set<storage::UseCrc32cValueOption>(kQuickFoxCrc32cChecksum)
                 .set<storage::UseMD5ValueOption>(BinaryMD5(kQuickFoxMD5Hash)),
             kQuickFoxCrc32cChecksum, kQuickFoxMD5Hash},
@@ -195,16 +223,16 @@ INSTANTIATE_TEST_SUITE_P(
         HashTestCase{
             StatusCode::kInvalidArgument,
             Options{}
-                .set<storage::EnableCrc32cValidationOption>(true)
-                .set<storage::EnableMD5ValidationOption>(true)
+                .set<storage::DownloadChecksumValidationOption>(
+                    storage::ChecksumAlgorithm::kCrc32c)
                 .set<storage::UseCrc32cValueOption>(kQuickFoxCrc32cChecksumBad)
                 .set<storage::UseMD5ValueOption>(BinaryMD5(kQuickFoxMD5Hash)),
             kQuickFoxCrc32cChecksum, kQuickFoxMD5Hash},
         HashTestCase{
             StatusCode::kInvalidArgument,
             Options{}
-                .set<storage::EnableCrc32cValidationOption>(true)
-                .set<storage::EnableMD5ValidationOption>(true)
+                .set<storage::DownloadChecksumValidationOption>(
+                    storage::ChecksumAlgorithm::kCrc32c)
                 .set<storage::UseCrc32cValueOption>(kQuickFoxCrc32cChecksum)
                 .set<storage::UseMD5ValueOption>(
                     BinaryMD5(kQuickFoxMD5HashBad)),
@@ -212,8 +240,8 @@ INSTANTIATE_TEST_SUITE_P(
         HashTestCase{
             StatusCode::kInvalidArgument,
             Options{}
-                .set<storage::EnableCrc32cValidationOption>(true)
-                .set<storage::EnableMD5ValidationOption>(true)
+                .set<storage::DownloadChecksumValidationOption>(
+                    storage::ChecksumAlgorithm::kCrc32c)
                 .set<storage::UseCrc32cValueOption>(kQuickFoxCrc32cChecksumBad)
                 .set<storage::UseMD5ValueOption>(
                     BinaryMD5(kQuickFoxMD5HashBad)),
diff --git a/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc b/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
index 14db6158db840..94cf30718a491 100644
--- a/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
+++ b/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
@@ -13,6 +13,17 @@
 // limitations under the License.
 
 #include "google/cloud/storage/async/options.h"
+
+// TODO: Remove this when EnableMD5ValidationOption and
+// EnableCrc32cValidationOption are removed.
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#endif
+
 #include "google/cloud/storage/async/writer_connection.h"
 #include "google/cloud/storage/internal/async/connection_impl.h"
 #include "google/cloud/storage/internal/async/default_options.h"
@@ -69,15 +80,21 @@ auto ExpectedObjectChecksums(HashTestCase const& tc) {
 
 std::ostream& operator<<(std::ostream& os, HashTestCase const& rhs) {
   os << "HashTestCase={options={";
-  os << std::boolalpha  //
-     << "enable_crc32c_validation="
-     << rhs.options.get<storage::EnableCrc32cValidationOption>();
+  os << std::boolalpha;  //
+  if (rhs.options.has<storage::UploadChecksumValidationOption>()) {
+    os << "upload_checksum="
+       << static_cast<int>(
+              rhs.options.get<storage::UploadChecksumValidationOption>());
+  } else {
+    os << "enable_crc32c_validation="
+       << rhs.options.get<storage::EnableCrc32cValidationOption>();
+    os << ", enable_md5_validation="
+       << rhs.options.get<storage::EnableMD5ValidationOption>();
+  }
   if (rhs.options.has<storage::UseCrc32cValueOption>()) {
     os << ", use_crc32_value="
        << rhs.options.get<storage::UseCrc32cValueOption>();
   }
-  os << ", enable_md5_validation="
-     << rhs.options.get<storage::EnableMD5ValidationOption>();
   if (rhs.options.has<storage::UseMD5ValueOption>()) {
     os << ", use_md5_value=" << rhs.options.get<storage::UseMD5ValueOption>();
   }
@@ -121,9 +138,8 @@ INSTANTIATE_TEST_SUITE_P(
                          .set<storage::EnableCrc32cValidationOption>(true)
                          .set<storage::EnableMD5ValidationOption>(true),
                      kQuickFoxCrc32cChecksum, kQuickFoxMD5Hash},
-        HashTestCase{Options{}
-                         .set<storage::EnableCrc32cValidationOption>(true)
-                         .set<storage::EnableMD5ValidationOption>(false),
+        HashTestCase{Options{}.set<storage::UploadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kCrc32c),
                      kQuickFoxCrc32cChecksum, ""},
         HashTestCase{Options{}
                          .set<storage::EnableCrc32cValidationOption>(false)
@@ -132,6 +148,12 @@ INSTANTIATE_TEST_SUITE_P(
         HashTestCase{Options{}
                          .set<storage::EnableCrc32cValidationOption>(false)
                          .set<storage::EnableMD5ValidationOption>(false),
+                     std::nullopt, ""},
+        HashTestCase{Options{}.set<storage::UploadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kMD5),
+                     std::nullopt, kQuickFoxMD5Hash},
+        HashTestCase{Options{}.set<storage::UploadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kNone),
                      std::nullopt, ""}));
 
 INSTANTIATE_TEST_SUITE_P(
@@ -139,26 +161,29 @@ INSTANTIATE_TEST_SUITE_P(
     ::testing::Values(
         HashTestCase{
             Options{}
-                .set<storage::EnableCrc32cValidationOption>(false)
-                .set<storage::EnableMD5ValidationOption>(false)
+                .set<storage::UploadChecksumValidationOption>(
+                    storage::ChecksumAlgorithm::kNone)
                 .set<storage::UseCrc32cValueOption>(kQuickFoxCrc32cChecksum)
                 .set<storage::UseMD5ValueOption>(BinaryMD5(kQuickFoxMD5Hash)),
             kQuickFoxCrc32cChecksum, kQuickFoxMD5Hash},
         HashTestCase{
             Options{}
-                .set<storage::EnableCrc32cValidationOption>(false)
-                .set<storage::EnableMD5ValidationOption>(false)
+                .set<storage::UploadChecksumValidationOption>(
+                    storage::ChecksumAlgorithm::kNone)
                 .set<storage::UseCrc32cValueOption>(kQuickFoxCrc32cChecksum),
             kQuickFoxCrc32cChecksum, ""},
         HashTestCase{
             Options{}
-                .set<storage::EnableCrc32cValidationOption>(false)
-                .set<storage::EnableMD5ValidationOption>(false)
+                .set<storage::UploadChecksumValidationOption>(
+                    storage::ChecksumAlgorithm::kNone)
                 .set<storage::UseMD5ValueOption>(BinaryMD5(kQuickFoxMD5Hash)),
             std::nullopt, kQuickFoxMD5Hash},
         HashTestCase{Options{}
                          .set<storage::EnableCrc32cValidationOption>(false)
                          .set<storage::EnableMD5ValidationOption>(false),
+                     std::nullopt, ""},
+        HashTestCase{Options{}.set<storage::UploadChecksumValidationOption>(
+                         storage::ChecksumAlgorithm::kNone),
                      std::nullopt, ""}));
 
 TEST_P(AsyncConnectionImplUploadHashTest, StartUnbuffered) {
diff --git a/google/cloud/storage/internal/async/default_options_test.cc b/google/cloud/storage/internal/async/default_options_test.cc
index dc7e4e8588be8..03ac3f40ca2fd 100644
--- a/google/cloud/storage/internal/async/default_options_test.cc
+++ b/google/cloud/storage/internal/async/default_options_test.cc
@@ -13,6 +13,17 @@
 // limitations under the License.
 
 #include "google/cloud/storage/internal/async/default_options.h"
+
+// TODO: Remove this when EnableMD5ValidationOption and
+// EnableCrc32cValidationOption are removed.
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#endif
+
 #include "google/cloud/storage/async/idempotency_policy.h"
 #include "google/cloud/storage/async/options.h"
 #include "google/cloud/storage/async/resume_policy.h"
diff --git a/google/cloud/storage/internal/async/object_descriptor_impl.cc b/google/cloud/storage/internal/async/object_descriptor_impl.cc
index 4a331b3a34f65..ae7a53aa32010 100644
--- a/google/cloud/storage/internal/async/object_descriptor_impl.cc
+++ b/google/cloud/storage/internal/async/object_descriptor_impl.cc
@@ -14,6 +14,7 @@
 
 #include "google/cloud/storage/internal/async/object_descriptor_impl.h"
 #include "google/cloud/storage/async/options.h"
+#include "google/cloud/storage/internal/async/checksum_helpers.h"
 #include "google/cloud/storage/internal/async/handle_redirect_error.h"
 #include "google/cloud/storage/internal/async/multi_stream_manager.h"
 #include "google/cloud/storage/internal/async/object_descriptor_reader_tracing.h"
@@ -23,6 +24,7 @@
 #include "google/cloud/storage/internal/hash_validator.h"
 #include "google/cloud/storage/internal/hash_validator_impl.h"
 #include "google/cloud/storage/internal/hash_values.h"
+#include "google/cloud/storage/options.h"
 #include "google/cloud/grpc_error_delegate.h"
 #include "google/cloud/internal/opentelemetry.h"
 #include "google/rpc/status.pb.h"
@@ -221,9 +223,8 @@ std::unique_ptr<storage::AsyncReaderConnection> ObjectDescriptorImpl::Read(
 
 std::shared_ptr<storage::internal::HashFunction>
 ObjectDescriptorImpl::CreateHashFunction(bool is_full_read) const {
-  auto const enable_crc32c =
-      options_.get<storage::EnableCrc32cValidationOption>();
-  auto const enable_md5 = options_.get<storage::EnableMD5ValidationOption>();
+  auto const [enable_crc32c, enable_md5] =
+      GetDownloadChecksumSettings(options_);
 
   if (enable_crc32c) {
     std::unique_ptr<storage::internal::HashFunction> child;
@@ -255,9 +256,8 @@ ObjectDescriptorImpl::CreateHashValidator(bool is_full_read) const {
     return storage::internal::CreateNullHashValidator();
   }
 
-  auto const enable_crc32c =
-      options_.get<storage::EnableCrc32cValidationOption>();
-  auto const enable_md5 = options_.get<storage::EnableMD5ValidationOption>();
+  auto const [enable_crc32c, enable_md5] =
+      GetDownloadChecksumSettings(options_);
 
   std::unique_ptr<storage::internal::HashValidator> hash_validator;
   if (enable_crc32c && enable_md5) {
diff --git a/google/cloud/storage/internal/async/object_descriptor_impl_test.cc b/google/cloud/storage/internal/async/object_descriptor_impl_test.cc
index 68169ed48d8a6..5f93213d32bad 100644
--- a/google/cloud/storage/internal/async/object_descriptor_impl_test.cc
+++ b/google/cloud/storage/internal/async/object_descriptor_impl_test.cc
@@ -13,6 +13,17 @@
 // limitations under the License.
 
 #include "google/cloud/storage/internal/async/object_descriptor_impl.h"
+
+// TODO: Remove this when EnableMD5ValidationOption and
+// EnableCrc32cValidationOption are removed.
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#endif
+
 #include "google/cloud/mocks/mock_async_streaming_read_write_rpc.h"
 #include "google/cloud/storage/async/options.h"
 #include "google/cloud/storage/async/resume_policy.h"
diff --git a/google/cloud/storage/internal/async/writer_connection_impl.cc b/google/cloud/storage/internal/async/writer_connection_impl.cc
index 59c4dce471365..fb0dbdc95bc4b 100644
--- a/google/cloud/storage/internal/async/writer_connection_impl.cc
+++ b/google/cloud/storage/internal/async/writer_connection_impl.cc
@@ -160,20 +160,18 @@ AsyncWriterConnectionImpl::Finalize(storage::WritePayload payload) {
           merged.get<google::cloud::storage::UseCrc32cValueOption>());
     }
     action = PartialUpload::kFinalize;
-  } else if (current_options
-                 .has<google::cloud::storage::UseCrc32cValueOption>() ||
-             current_options.has<google::cloud::storage::UseMD5ValueOption>()) {
-    // If the user specified a manual expected checksum dynamically at
-    // Finalize() via current_options, we manually inject it and use `kFinalize`
-    // so the internal hash function doesn't overwrite it with its own computed
-    // hash.
-    if (current_options.has<google::cloud::storage::UseCrc32cValueOption>()) {
+  } else if (merged.has<google::cloud::storage::UseCrc32cValueOption>() ||
+             merged.has<google::cloud::storage::UseMD5ValueOption>()) {
+    // If the user specified a manual expected checksum, we manually inject it
+    // and use `kFinalize` so the internal hash function doesn't overwrite it
+    // with its own computed hash.
+    if (merged.has<google::cloud::storage::UseCrc32cValueOption>()) {
       write.mutable_object_checksums()->set_crc32c(
-          current_options.get<google::cloud::storage::UseCrc32cValueOption>());
+          merged.get<google::cloud::storage::UseCrc32cValueOption>());
     }
-    if (current_options.has<google::cloud::storage::UseMD5ValueOption>()) {
+    if (merged.has<google::cloud::storage::UseMD5ValueOption>()) {
       write.mutable_object_checksums()->set_md5_hash(
-          current_options.get<google::cloud::storage::UseMD5ValueOption>());
+          merged.get<google::cloud::storage::UseMD5ValueOption>());
     }
     action = PartialUpload::kFinalize;
   }
diff --git a/google/cloud/storage/tests/async_client_integration_test.cc b/google/cloud/storage/tests/async_client_integration_test.cc
index e383aeee30f14..aae9bfc02f1f9 100644
--- a/google/cloud/storage/tests/async_client_integration_test.cc
+++ b/google/cloud/storage/tests/async_client_integration_test.cc
@@ -1006,11 +1006,12 @@ TEST_F(AsyncClientIntegrationTest, Open) {
 
 TEST_F(AsyncClientIntegrationTest, OpenExceedMaximumRange) {
   if (!UsingEmulator()) GTEST_SKIP();
-  auto async =
-      AsyncClient(TestOptions()
-                      .set<storage::MaximumRangeSizeOption>(1024)
-                      .set<storage::EnableCrc32cValidationOption>(false)
-                      .set<storage::EnableMD5ValidationOption>(false));
+  auto async = AsyncClient(TestOptions()
+                               .set<storage::MaximumRangeSizeOption>(1024)
+                               .set<storage::UploadChecksumValidationOption>(
+                                   storage::ChecksumAlgorithm::kNone)
+                               .set<storage::DownloadChecksumValidationOption>(
+                                   storage::ChecksumAlgorithm::kNone));
   auto client = MakeIntegrationTestClient(true, TestOptions());
   auto object_name = MakeRandomObjectName();
 
@@ -1065,8 +1066,10 @@ TEST_F(AsyncClientIntegrationTest, OpenExceedMaximumRange) {
 TEST_F(AsyncClientIntegrationTest, OpenWithChecksumValidation) {
   if (!UsingEmulator()) GTEST_SKIP();
   auto async = AsyncClient(TestOptions()
-                               .set<storage::EnableCrc32cValidationOption>(true)
-                               .set<storage::EnableMD5ValidationOption>(true));
+                               .set<storage::UploadChecksumValidationOption>(
+                                   storage::ChecksumAlgorithm::kCrc32c)
+                               .set<storage::DownloadChecksumValidationOption>(
+                                   storage::ChecksumAlgorithm::kCrc32c));
   auto client = MakeIntegrationTestClient(true, TestOptions());
   auto object_name = MakeRandomObjectName();
 

From a5ea1880c962a47485f863343a406a1c8d4020da Mon Sep 17 00:00:00 2001
From: Vaibhav Pratap <vaibhavpratap85@gmail.com>
Date: Wed, 15 Jul 2026 14:14:38 +0000
Subject: [PATCH 02/12] fix(storage): address reviewer comments and fix format

---
 .../storage/internal/async/connection_impl.cc | 21 +++++++++----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/google/cloud/storage/internal/async/connection_impl.cc b/google/cloud/storage/internal/async/connection_impl.cc
index 60e6d77879407..3f2c0cbbb295f 100644
--- a/google/cloud/storage/internal/async/connection_impl.cc
+++ b/google/cloud/storage/internal/async/connection_impl.cc
@@ -423,7 +423,7 @@ AsyncConnectionImpl::AppendableObjectUploadImpl(AppendableUploadParams p) {
   return pending.then(
       [current, request = std::move(p.request), hash = std::move(hash_function),
        fa = std::move(factory)](auto f) mutable
-          -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+      -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
         auto rpc = f.get();
         if (!rpc) return std::move(rpc).status();
         std::unique_ptr<AsyncWriterConnectionImpl> impl;
@@ -478,7 +478,7 @@ AsyncConnectionImpl::StartBufferedUpload(UploadParams p) {
   return StartUnbufferedUpload(std::move(p))
       .then([current = std::move(current),
              async_write_object = std::move(async_write_object)](auto f) mutable
-                -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+            -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
         auto w = f.get();
         if (!w) return std::move(w).status();
         auto factory = [upload_id = (*w)->UploadId(),
@@ -512,15 +512,14 @@ AsyncConnectionImpl::ResumeBufferedUpload(ResumeUploadParams p) {
   };
 
   auto f = make_unbuffered();
-  return f.then(
-      [current = std::move(current),
-       make_unbuffered = std::move(make_unbuffered)](auto f) mutable
-          -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
-        auto w = f.get();
-        if (!w) return std::move(w).status();
-        return MakeWriterConnectionBuffered(std::move(make_unbuffered),
-                                            *std::move(w), *current);
-      });
+  return f.then([current = std::move(current),
+                 make_unbuffered = std::move(make_unbuffered)](auto f) mutable
+                -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+    auto w = f.get();
+    if (!w) return std::move(w).status();
+    return MakeWriterConnectionBuffered(std::move(make_unbuffered),
+                                        *std::move(w), *current);
+  });
 }
 
 future<StatusOr<google::storage::v2::Object>>

From 2473a8c9dcc123adbb09b89ba4d3dd0361dcc07e Mon Sep 17 00:00:00 2001
From: Vaibhav Pratap <vaibhavpratap85@gmail.com>
Date: Wed, 15 Jul 2026 15:17:12 +0000
Subject: [PATCH 03/12] fix: resolve review comments and unit tests failures

---
 .../storage/internal/async/connection_impl.cc | 25 +++++++++++--------
 .../internal/async/object_descriptor_impl.cc  | 10 +++++---
 .../internal/async/writer_connection_impl.cc  | 20 ++++++++-------
 3 files changed, 31 insertions(+), 24 deletions(-)

diff --git a/google/cloud/storage/internal/async/connection_impl.cc b/google/cloud/storage/internal/async/connection_impl.cc
index 3f2c0cbbb295f..2bc2c35251d37 100644
--- a/google/cloud/storage/internal/async/connection_impl.cc
+++ b/google/cloud/storage/internal/async/connection_impl.cc
@@ -130,7 +130,9 @@ std::unique_ptr<storage::internal::HashValidator> CreateHashValidator(
       request.read_limit() != 0 || request.read_offset() != 0;
   if (is_ranged_read) return storage::internal::CreateNullHashValidator();
 
-  auto const [enable_crc32c, enable_md5] = GetDownloadChecksumSettings(options);
+  auto const settings = GetDownloadChecksumSettings(options);
+  auto const enable_crc32c = settings.enable_crc32c;
+  auto const enable_md5 = settings.enable_md5;
 
   if (enable_crc32c && enable_md5) {
     return std::make_unique<storage::internal::CompositeValidator>(
@@ -423,7 +425,7 @@ AsyncConnectionImpl::AppendableObjectUploadImpl(AppendableUploadParams p) {
   return pending.then(
       [current, request = std::move(p.request), hash = std::move(hash_function),
        fa = std::move(factory)](auto f) mutable
-      -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+          -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
         auto rpc = f.get();
         if (!rpc) return std::move(rpc).status();
         std::unique_ptr<AsyncWriterConnectionImpl> impl;
@@ -478,7 +480,7 @@ AsyncConnectionImpl::StartBufferedUpload(UploadParams p) {
   return StartUnbufferedUpload(std::move(p))
       .then([current = std::move(current),
              async_write_object = std::move(async_write_object)](auto f) mutable
-            -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+                -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
         auto w = f.get();
         if (!w) return std::move(w).status();
         auto factory = [upload_id = (*w)->UploadId(),
@@ -512,14 +514,15 @@ AsyncConnectionImpl::ResumeBufferedUpload(ResumeUploadParams p) {
   };
 
   auto f = make_unbuffered();
-  return f.then([current = std::move(current),
-                 make_unbuffered = std::move(make_unbuffered)](auto f) mutable
-                -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
-    auto w = f.get();
-    if (!w) return std::move(w).status();
-    return MakeWriterConnectionBuffered(std::move(make_unbuffered),
-                                        *std::move(w), *current);
-  });
+  return f.then(
+      [current = std::move(current),
+       make_unbuffered = std::move(make_unbuffered)](auto f) mutable
+          -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+        auto w = f.get();
+        if (!w) return std::move(w).status();
+        return MakeWriterConnectionBuffered(std::move(make_unbuffered),
+                                            *std::move(w), *current);
+      });
 }
 
 future<StatusOr<google::storage::v2::Object>>
diff --git a/google/cloud/storage/internal/async/object_descriptor_impl.cc b/google/cloud/storage/internal/async/object_descriptor_impl.cc
index ae7a53aa32010..9430880b8d966 100644
--- a/google/cloud/storage/internal/async/object_descriptor_impl.cc
+++ b/google/cloud/storage/internal/async/object_descriptor_impl.cc
@@ -223,8 +223,9 @@ std::unique_ptr<storage::AsyncReaderConnection> ObjectDescriptorImpl::Read(
 
 std::shared_ptr<storage::internal::HashFunction>
 ObjectDescriptorImpl::CreateHashFunction(bool is_full_read) const {
-  auto const [enable_crc32c, enable_md5] =
-      GetDownloadChecksumSettings(options_);
+  auto const settings = GetDownloadChecksumSettings(options_);
+  auto const enable_crc32c = settings.enable_crc32c;
+  auto const enable_md5 = settings.enable_md5;
 
   if (enable_crc32c) {
     std::unique_ptr<storage::internal::HashFunction> child;
@@ -256,8 +257,9 @@ ObjectDescriptorImpl::CreateHashValidator(bool is_full_read) const {
     return storage::internal::CreateNullHashValidator();
   }
 
-  auto const [enable_crc32c, enable_md5] =
-      GetDownloadChecksumSettings(options_);
+  auto const settings = GetDownloadChecksumSettings(options_);
+  auto const enable_crc32c = settings.enable_crc32c;
+  auto const enable_md5 = settings.enable_md5;
 
   std::unique_ptr<storage::internal::HashValidator> hash_validator;
   if (enable_crc32c && enable_md5) {
diff --git a/google/cloud/storage/internal/async/writer_connection_impl.cc b/google/cloud/storage/internal/async/writer_connection_impl.cc
index fb0dbdc95bc4b..59c4dce471365 100644
--- a/google/cloud/storage/internal/async/writer_connection_impl.cc
+++ b/google/cloud/storage/internal/async/writer_connection_impl.cc
@@ -160,18 +160,20 @@ AsyncWriterConnectionImpl::Finalize(storage::WritePayload payload) {
           merged.get<google::cloud::storage::UseCrc32cValueOption>());
     }
     action = PartialUpload::kFinalize;
-  } else if (merged.has<google::cloud::storage::UseCrc32cValueOption>() ||
-             merged.has<google::cloud::storage::UseMD5ValueOption>()) {
-    // If the user specified a manual expected checksum, we manually inject it
-    // and use `kFinalize` so the internal hash function doesn't overwrite it
-    // with its own computed hash.
-    if (merged.has<google::cloud::storage::UseCrc32cValueOption>()) {
+  } else if (current_options
+                 .has<google::cloud::storage::UseCrc32cValueOption>() ||
+             current_options.has<google::cloud::storage::UseMD5ValueOption>()) {
+    // If the user specified a manual expected checksum dynamically at
+    // Finalize() via current_options, we manually inject it and use `kFinalize`
+    // so the internal hash function doesn't overwrite it with its own computed
+    // hash.
+    if (current_options.has<google::cloud::storage::UseCrc32cValueOption>()) {
       write.mutable_object_checksums()->set_crc32c(
-          merged.get<google::cloud::storage::UseCrc32cValueOption>());
+          current_options.get<google::cloud::storage::UseCrc32cValueOption>());
     }
-    if (merged.has<google::cloud::storage::UseMD5ValueOption>()) {
+    if (current_options.has<google::cloud::storage::UseMD5ValueOption>()) {
       write.mutable_object_checksums()->set_md5_hash(
-          merged.get<google::cloud::storage::UseMD5ValueOption>());
+          current_options.get<google::cloud::storage::UseMD5ValueOption>());
     }
     action = PartialUpload::kFinalize;
   }

From 5228545802a123df131e23aa56d3f0c230fd4694 Mon Sep 17 00:00:00 2001
From: Vaibhav Pratap <vaibhavpratap85@gmail.com>
Date: Wed, 15 Jul 2026 16:03:24 +0000
Subject: [PATCH 04/12] fix(storage): clang-format style issues in
 connection_impl.cc

---
 .../storage/internal/async/connection_impl.cc | 21 +++++++++----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/google/cloud/storage/internal/async/connection_impl.cc b/google/cloud/storage/internal/async/connection_impl.cc
index 2bc2c35251d37..d2f43c67169d9 100644
--- a/google/cloud/storage/internal/async/connection_impl.cc
+++ b/google/cloud/storage/internal/async/connection_impl.cc
@@ -425,7 +425,7 @@ AsyncConnectionImpl::AppendableObjectUploadImpl(AppendableUploadParams p) {
   return pending.then(
       [current, request = std::move(p.request), hash = std::move(hash_function),
        fa = std::move(factory)](auto f) mutable
-          -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+      -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
         auto rpc = f.get();
         if (!rpc) return std::move(rpc).status();
         std::unique_ptr<AsyncWriterConnectionImpl> impl;
@@ -480,7 +480,7 @@ AsyncConnectionImpl::StartBufferedUpload(UploadParams p) {
   return StartUnbufferedUpload(std::move(p))
       .then([current = std::move(current),
              async_write_object = std::move(async_write_object)](auto f) mutable
-                -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+            -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
         auto w = f.get();
         if (!w) return std::move(w).status();
         auto factory = [upload_id = (*w)->UploadId(),
@@ -514,15 +514,14 @@ AsyncConnectionImpl::ResumeBufferedUpload(ResumeUploadParams p) {
   };
 
   auto f = make_unbuffered();
-  return f.then(
-      [current = std::move(current),
-       make_unbuffered = std::move(make_unbuffered)](auto f) mutable
-          -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
-        auto w = f.get();
-        if (!w) return std::move(w).status();
-        return MakeWriterConnectionBuffered(std::move(make_unbuffered),
-                                            *std::move(w), *current);
-      });
+  return f.then([current = std::move(current),
+                 make_unbuffered = std::move(make_unbuffered)](auto f) mutable
+                -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+    auto w = f.get();
+    if (!w) return std::move(w).status();
+    return MakeWriterConnectionBuffered(std::move(make_unbuffered),
+                                        *std::move(w), *current);
+  });
 }
 
 future<StatusOr<google::storage::v2::Object>>

From 14245280be4e027109fc35e6070ebab95b99e5b6 Mon Sep 17 00:00:00 2001
From: Vaibhav Pratap <vaibhavpratap85@gmail.com>
Date: Wed, 15 Jul 2026 16:18:00 +0000
Subject: [PATCH 05/12] fix: address PR review comments for read hash tests and
 upload checksum helper

---
 .../storage/internal/async/checksum_helpers.h      | 10 ++++++++++
 .../storage/internal/async/connection_impl.cc      | 14 +++-----------
 .../async/connection_impl_read_hash_test.cc        | 14 ++++++++------
 3 files changed, 21 insertions(+), 17 deletions(-)

diff --git a/google/cloud/storage/internal/async/checksum_helpers.h b/google/cloud/storage/internal/async/checksum_helpers.h
index eb8bd14cc3bfa..9937c75945236 100644
--- a/google/cloud/storage/internal/async/checksum_helpers.h
+++ b/google/cloud/storage/internal/async/checksum_helpers.h
@@ -40,6 +40,16 @@ inline ChecksumSettings GetDownloadChecksumSettings(Options const& options) {
           options.get<storage::EnableMD5ValidationOption>()};
 }
 
+inline ChecksumSettings GetUploadChecksumSettings(Options const& options) {
+  if (options.has<storage::UploadChecksumValidationOption>()) {
+    auto const algo = options.get<storage::UploadChecksumValidationOption>();
+    return {algo == storage::ChecksumAlgorithm::kCrc32c,
+            algo == storage::ChecksumAlgorithm::kMD5};
+  }
+  return {options.get<storage::EnableCrc32cValidationOption>(),
+          options.get<storage::EnableMD5ValidationOption>()};
+}
+
 GOOGLE_CLOUD_CPP_INLINE_NAMESPACE_END
 }  // namespace storage_internal
 }  // namespace cloud
diff --git a/google/cloud/storage/internal/async/connection_impl.cc b/google/cloud/storage/internal/async/connection_impl.cc
index d2f43c67169d9..f5e1a63cb07fb 100644
--- a/google/cloud/storage/internal/async/connection_impl.cc
+++ b/google/cloud/storage/internal/async/connection_impl.cc
@@ -83,17 +83,9 @@ inline std::unique_ptr<storage::AsyncIdempotencyPolicy> idempotency_policy(
 std::unique_ptr<storage::internal::HashFunction> CreateHashFunction(
     Options const& options) {
   auto crc32c = std::unique_ptr<storage::internal::HashFunction>();
-  bool enable_crc32c = false;
-  bool enable_md5 = false;
-
-  if (options.has<storage::UploadChecksumValidationOption>()) {
-    auto const algo = options.get<storage::UploadChecksumValidationOption>();
-    enable_crc32c = (algo == storage::ChecksumAlgorithm::kCrc32c);
-    enable_md5 = (algo == storage::ChecksumAlgorithm::kMD5);
-  } else {
-    enable_crc32c = options.get<storage::EnableCrc32cValidationOption>();
-    enable_md5 = options.get<storage::EnableMD5ValidationOption>();
-  }
+  auto const settings = GetUploadChecksumSettings(options);
+  auto const enable_crc32c = settings.enable_crc32c;
+  auto const enable_md5 = settings.enable_md5;
 
   if (options.has<storage::UseCrc32cValueOption>()) {
     crc32c = std::make_unique<storage::internal::PrecomputedHashFunction>(
diff --git a/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc b/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
index 2fbb3a2f6e6df..c07c382dd94ea 100644
--- a/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
+++ b/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
@@ -157,8 +157,9 @@ INSTANTIATE_TEST_SUITE_P(
             kQuickFoxCrc32cChecksum, ""},
         // Make sure things work when both hashes are validated too.
         HashTestCase{StatusCode::kOk,
-                     Options{}.set<storage::DownloadChecksumValidationOption>(
-                         storage::ChecksumAlgorithm::kNone),
+                     Options{}
+                         .set<storage::EnableCrc32cValidationOption>(true)
+                         .set<storage::EnableMD5ValidationOption>(true),
                      kQuickFoxCrc32cChecksum, kQuickFoxMD5Hash},
         // In the next three cases we verify that disabling some validation
         // works.
@@ -197,8 +198,9 @@ INSTANTIATE_TEST_SUITE_P(
                          storage::ChecksumAlgorithm::kCrc32c),
                      kQuickFoxCrc32cChecksumBad, kQuickFoxMD5HashBad},
         HashTestCase{StatusCode::kInvalidArgument,
-                     Options{}.set<storage::DownloadChecksumValidationOption>(
-                         storage::ChecksumAlgorithm::kNone),
+                     Options{}
+                         .set<storage::EnableCrc32cValidationOption>(true)
+                         .set<storage::EnableMD5ValidationOption>(true),
                      kQuickFoxCrc32cChecksumBad, kQuickFoxMD5HashBad},
         HashTestCase{StatusCode::kInvalidArgument,
                      Options{}.set<storage::DownloadChecksumValidationOption>(
@@ -231,8 +233,8 @@ INSTANTIATE_TEST_SUITE_P(
         HashTestCase{
             StatusCode::kInvalidArgument,
             Options{}
-                .set<storage::DownloadChecksumValidationOption>(
-                    storage::ChecksumAlgorithm::kCrc32c)
+                .set<storage::EnableCrc32cValidationOption>(true)
+                .set<storage::EnableMD5ValidationOption>(true)
                 .set<storage::UseCrc32cValueOption>(kQuickFoxCrc32cChecksum)
                 .set<storage::UseMD5ValueOption>(
                     BinaryMD5(kQuickFoxMD5HashBad)),

From b76b819fb351b9bd67c4e8ce7584b3cb73fa6ba3 Mon Sep 17 00:00:00 2001
From: Vaibhav Pratap <vaibhavpratap85@gmail.com>
Date: Wed, 15 Jul 2026 18:57:32 +0000
Subject: [PATCH 06/12] fix(storage): resolve read hash tests failing due to
 incorrect checksum settings

---
 .../storage/internal/async/connection_impl.cc | 39 +++++++++++--------
 1 file changed, 22 insertions(+), 17 deletions(-)

diff --git a/google/cloud/storage/internal/async/connection_impl.cc b/google/cloud/storage/internal/async/connection_impl.cc
index f5e1a63cb07fb..735f756eb77f0 100644
--- a/google/cloud/storage/internal/async/connection_impl.cc
+++ b/google/cloud/storage/internal/async/connection_impl.cc
@@ -81,9 +81,9 @@ inline std::unique_ptr<storage::AsyncIdempotencyPolicy> idempotency_policy(
 }
 
 std::unique_ptr<storage::internal::HashFunction> CreateHashFunction(
-    Options const& options) {
+    Options const& options,
+    storage_internal::ChecksumSettings const& settings) {
   auto crc32c = std::unique_ptr<storage::internal::HashFunction>();
-  auto const settings = GetUploadChecksumSettings(options);
   auto const enable_crc32c = settings.enable_crc32c;
   auto const enable_md5 = settings.enable_md5;
 
@@ -172,7 +172,8 @@ future<StatusOr<google::storage::v2::Object>> AsyncConnectionImpl::InsertObject(
         options->get<storage::TransferStallMinimumRateOption>(),
         google::storage::v2::ServiceConstants::MAX_WRITE_CHUNK_BYTES);
 
-    auto hash_function = CreateHashFunction(*options);
+    auto hash_function =
+        CreateHashFunction(*options, GetUploadChecksumSettings(*options));
     ApplyRoutingHeaders(*context, request.write_object_spec());
     AddIdempotencyToken(*context, id);
     auto rpc = stub->AsyncWriteObject(cq, std::move(context), options);
@@ -276,9 +277,10 @@ AsyncConnectionImpl::ReadObject(ReadObjectParams p) {
   // Create the hash function and validator based on the original request. Note
   // that p.request will be moved-from, so we have to do it relatively early in
   // this function.
+  auto const settings = GetDownloadChecksumSettings(*current);
   auto hash_function =
       std::make_shared<storage::internal::Crc32cMessageHashFunction>(
-          CreateHashFunction(*current));
+          CreateHashFunction(*current, settings));
   auto hash_validator = CreateHashValidator(p.request, *current);
 
   std::optional<std::int64_t> requested_length;
@@ -328,7 +330,7 @@ AsyncConnectionImpl::AppendableObjectUploadImpl(AppendableUploadParams p) {
   auto current = internal::MakeImmutableOptions(std::move(p.options));
   auto request = p.request;
   std::shared_ptr<storage::internal::HashFunction> hash_function =
-      CreateHashFunction(*current);
+      CreateHashFunction(*current, GetUploadChecksumSettings(*current));
   auto retry =
       std::shared_ptr<storage::AsyncRetryPolicy>(retry_policy(*current));
   auto backoff =
@@ -417,7 +419,7 @@ AsyncConnectionImpl::AppendableObjectUploadImpl(AppendableUploadParams p) {
   return pending.then(
       [current, request = std::move(p.request), hash = std::move(hash_function),
        fa = std::move(factory)](auto f) mutable
-      -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+          -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
         auto rpc = f.get();
         if (!rpc) return std::move(rpc).status();
         std::unique_ptr<AsyncWriterConnectionImpl> impl;
@@ -472,7 +474,7 @@ AsyncConnectionImpl::StartBufferedUpload(UploadParams p) {
   return StartUnbufferedUpload(std::move(p))
       .then([current = std::move(current),
              async_write_object = std::move(async_write_object)](auto f) mutable
-            -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+                -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
         auto w = f.get();
         if (!w) return std::move(w).status();
         auto factory = [upload_id = (*w)->UploadId(),
@@ -506,14 +508,15 @@ AsyncConnectionImpl::ResumeBufferedUpload(ResumeUploadParams p) {
   };
 
   auto f = make_unbuffered();
-  return f.then([current = std::move(current),
-                 make_unbuffered = std::move(make_unbuffered)](auto f) mutable
-                -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
-    auto w = f.get();
-    if (!w) return std::move(w).status();
-    return MakeWriterConnectionBuffered(std::move(make_unbuffered),
-                                        *std::move(w), *current);
-  });
+  return f.then(
+      [current = std::move(current),
+       make_unbuffered = std::move(make_unbuffered)](auto f) mutable
+          -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+        auto w = f.get();
+        if (!w) return std::move(w).status();
+        return MakeWriterConnectionBuffered(std::move(make_unbuffered),
+                                            *std::move(w), *current);
+      });
 }
 
 future<StatusOr<google::storage::v2::Object>>
@@ -708,7 +711,8 @@ AsyncConnectionImpl::StartUnbufferedUploadImpl(
         StatusOr<std::unique_ptr<storage::AsyncWriterConnection>>(
             std::move(response).status()));
   }
-  auto hash_function = CreateHashFunction(*current);
+  auto hash_function =
+      CreateHashFunction(*current, GetUploadChecksumSettings(*current));
   auto configure =
       [current, upload = response->upload_id()](grpc::ClientContext& context) {
         ApplyResumableUploadRoutingHeader(context, upload);
@@ -746,7 +750,8 @@ AsyncConnectionImpl::ResumeUnbufferedUploadImpl(
   // the upload resumes from the beginning of the file.
   auto hash_function = storage::internal::CreateNullHashFunction();
   if (response->persisted_size() == 0) {
-    hash_function = CreateHashFunction(*current);
+    hash_function =
+        CreateHashFunction(*current, GetUploadChecksumSettings(*current));
   }
   auto configure =
       [current, upload_id = query.upload_id()](grpc::ClientContext& context) {

From 39c4a25bc7e1b1180c07bc356a1260b55a70f097 Mon Sep 17 00:00:00 2001
From: Vaibhav Pratap <vaibhavpratap85@gmail.com>
Date: Thu, 16 Jul 2026 10:01:19 +0000
Subject: [PATCH 07/12] fix(storage): resolve clang-format style issues

---
 .../storage/internal/async/connection_impl.cc | 21 +++++++++----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/google/cloud/storage/internal/async/connection_impl.cc b/google/cloud/storage/internal/async/connection_impl.cc
index 735f756eb77f0..cc3de87521cab 100644
--- a/google/cloud/storage/internal/async/connection_impl.cc
+++ b/google/cloud/storage/internal/async/connection_impl.cc
@@ -419,7 +419,7 @@ AsyncConnectionImpl::AppendableObjectUploadImpl(AppendableUploadParams p) {
   return pending.then(
       [current, request = std::move(p.request), hash = std::move(hash_function),
        fa = std::move(factory)](auto f) mutable
-          -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+      -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
         auto rpc = f.get();
         if (!rpc) return std::move(rpc).status();
         std::unique_ptr<AsyncWriterConnectionImpl> impl;
@@ -474,7 +474,7 @@ AsyncConnectionImpl::StartBufferedUpload(UploadParams p) {
   return StartUnbufferedUpload(std::move(p))
       .then([current = std::move(current),
              async_write_object = std::move(async_write_object)](auto f) mutable
-                -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+            -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
         auto w = f.get();
         if (!w) return std::move(w).status();
         auto factory = [upload_id = (*w)->UploadId(),
@@ -508,15 +508,14 @@ AsyncConnectionImpl::ResumeBufferedUpload(ResumeUploadParams p) {
   };
 
   auto f = make_unbuffered();
-  return f.then(
-      [current = std::move(current),
-       make_unbuffered = std::move(make_unbuffered)](auto f) mutable
-          -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
-        auto w = f.get();
-        if (!w) return std::move(w).status();
-        return MakeWriterConnectionBuffered(std::move(make_unbuffered),
-                                            *std::move(w), *current);
-      });
+  return f.then([current = std::move(current),
+                 make_unbuffered = std::move(make_unbuffered)](auto f) mutable
+                -> StatusOr<std::unique_ptr<storage::AsyncWriterConnection>> {
+    auto w = f.get();
+    if (!w) return std::move(w).status();
+    return MakeWriterConnectionBuffered(std::move(make_unbuffered),
+                                        *std::move(w), *current);
+  });
 }
 
 future<StatusOr<google::storage::v2::Object>>

From c0cf77bc7101265d592693654eb2d5c396e0edac Mon Sep 17 00:00:00 2001
From: Vaibhav Pratap <vaibhavpratap85@gmail.com>
Date: Fri, 17 Jul 2026 09:16:49 +0000
Subject: [PATCH 08/12] fix(storage): resolve reviewer comments for read hash
 tests and upload checksum helper

---
 .../internal/async/connection_impl_read_hash_test.cc   | 10 ----------
 .../internal/async/connection_impl_upload_hash_test.cc | 10 ----------
 .../storage/internal/async/default_options_test.cc     | 10 ----------
 .../internal/async/object_descriptor_impl_test.cc      | 10 ----------
 4 files changed, 40 deletions(-)

diff --git a/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc b/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
index c07c382dd94ea..ff49d65efe113 100644
--- a/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
+++ b/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
@@ -14,16 +14,6 @@
 
 #include "google/cloud/storage/async/options.h"
 
-// TODO: Remove this when EnableMD5ValidationOption and
-// EnableCrc32cValidationOption are removed.
-#if defined(__GNUC__) && !defined(__clang__)
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
-#elif defined(__clang__)
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wdeprecated-declarations"
-#endif
-
 #include "google/cloud/storage/internal/async/connection_impl.h"
 #include "google/cloud/storage/internal/async/default_options.h"
 #include "google/cloud/storage/internal/crc32c.h"
diff --git a/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc b/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
index 94cf30718a491..656374a389c82 100644
--- a/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
+++ b/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
@@ -14,16 +14,6 @@
 
 #include "google/cloud/storage/async/options.h"
 
-// TODO: Remove this when EnableMD5ValidationOption and
-// EnableCrc32cValidationOption are removed.
-#if defined(__GNUC__) && !defined(__clang__)
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
-#elif defined(__clang__)
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wdeprecated-declarations"
-#endif
-
 #include "google/cloud/storage/async/writer_connection.h"
 #include "google/cloud/storage/internal/async/connection_impl.h"
 #include "google/cloud/storage/internal/async/default_options.h"
diff --git a/google/cloud/storage/internal/async/default_options_test.cc b/google/cloud/storage/internal/async/default_options_test.cc
index 03ac3f40ca2fd..3c7a6a2a17862 100644
--- a/google/cloud/storage/internal/async/default_options_test.cc
+++ b/google/cloud/storage/internal/async/default_options_test.cc
@@ -14,16 +14,6 @@
 
 #include "google/cloud/storage/internal/async/default_options.h"
 
-// TODO: Remove this when EnableMD5ValidationOption and
-// EnableCrc32cValidationOption are removed.
-#if defined(__GNUC__) && !defined(__clang__)
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
-#elif defined(__clang__)
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wdeprecated-declarations"
-#endif
-
 #include "google/cloud/storage/async/idempotency_policy.h"
 #include "google/cloud/storage/async/options.h"
 #include "google/cloud/storage/async/resume_policy.h"
diff --git a/google/cloud/storage/internal/async/object_descriptor_impl_test.cc b/google/cloud/storage/internal/async/object_descriptor_impl_test.cc
index 5f93213d32bad..782d818a02a1a 100644
--- a/google/cloud/storage/internal/async/object_descriptor_impl_test.cc
+++ b/google/cloud/storage/internal/async/object_descriptor_impl_test.cc
@@ -14,16 +14,6 @@
 
 #include "google/cloud/storage/internal/async/object_descriptor_impl.h"
 
-// TODO: Remove this when EnableMD5ValidationOption and
-// EnableCrc32cValidationOption are removed.
-#if defined(__GNUC__) && !defined(__clang__)
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
-#elif defined(__clang__)
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wdeprecated-declarations"
-#endif
-
 #include "google/cloud/mocks/mock_async_streaming_read_write_rpc.h"
 #include "google/cloud/storage/async/options.h"
 #include "google/cloud/storage/async/resume_policy.h"

From 23bb221f42f172c15c9dfcd5048d0af0345a19b5 Mon Sep 17 00:00:00 2001
From: Vaibhav Pratap <vaibhavpratap85@gmail.com>
Date: Fri, 17 Jul 2026 09:43:07 +0000
Subject: [PATCH 09/12] fix(storage): resolve clang format

---
 .../storage/internal/async/connection_impl_read_hash_test.cc     | 1 -
 .../storage/internal/async/connection_impl_upload_hash_test.cc   | 1 -
 google/cloud/storage/internal/async/default_options_test.cc      | 1 -
 .../cloud/storage/internal/async/object_descriptor_impl_test.cc  | 1 -
 4 files changed, 4 deletions(-)

diff --git a/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc b/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
index ff49d65efe113..7904fa2fc79ed 100644
--- a/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
+++ b/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
@@ -13,7 +13,6 @@
 // limitations under the License.
 
 #include "google/cloud/storage/async/options.h"
-
 #include "google/cloud/storage/internal/async/connection_impl.h"
 #include "google/cloud/storage/internal/async/default_options.h"
 #include "google/cloud/storage/internal/crc32c.h"
diff --git a/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc b/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
index 656374a389c82..ae8b3e6a2318e 100644
--- a/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
+++ b/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
@@ -13,7 +13,6 @@
 // limitations under the License.
 
 #include "google/cloud/storage/async/options.h"
-
 #include "google/cloud/storage/async/writer_connection.h"
 #include "google/cloud/storage/internal/async/connection_impl.h"
 #include "google/cloud/storage/internal/async/default_options.h"
diff --git a/google/cloud/storage/internal/async/default_options_test.cc b/google/cloud/storage/internal/async/default_options_test.cc
index 3c7a6a2a17862..dc7e4e8588be8 100644
--- a/google/cloud/storage/internal/async/default_options_test.cc
+++ b/google/cloud/storage/internal/async/default_options_test.cc
@@ -13,7 +13,6 @@
 // limitations under the License.
 
 #include "google/cloud/storage/internal/async/default_options.h"
-
 #include "google/cloud/storage/async/idempotency_policy.h"
 #include "google/cloud/storage/async/options.h"
 #include "google/cloud/storage/async/resume_policy.h"
diff --git a/google/cloud/storage/internal/async/object_descriptor_impl_test.cc b/google/cloud/storage/internal/async/object_descriptor_impl_test.cc
index 782d818a02a1a..68169ed48d8a6 100644
--- a/google/cloud/storage/internal/async/object_descriptor_impl_test.cc
+++ b/google/cloud/storage/internal/async/object_descriptor_impl_test.cc
@@ -13,7 +13,6 @@
 // limitations under the License.
 
 #include "google/cloud/storage/internal/async/object_descriptor_impl.h"
-
 #include "google/cloud/mocks/mock_async_streaming_read_write_rpc.h"
 #include "google/cloud/storage/async/options.h"
 #include "google/cloud/storage/async/resume_policy.h"

From e6d1487c8437a645a7d1427c478099724b579174 Mon Sep 17 00:00:00 2001
From: Vaibhav Pratap <vaibhavpratap85@gmail.com>
Date: Fri, 17 Jul 2026 09:55:43 +0000
Subject: [PATCH 10/12] fix(storage): add missing TODO username and disable
 deprecation warnings for tests

---
 .../storage/internal/async/connection_impl_read_hash_test.cc | 5 +++++
 .../internal/async/connection_impl_upload_hash_test.cc       | 5 +++++
 google/cloud/storage/internal/async/default_options_test.cc  | 5 +++++
 .../storage/internal/async/object_descriptor_impl_test.cc    | 5 +++++
 4 files changed, 20 insertions(+)

diff --git a/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc b/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
index 7904fa2fc79ed..35ad8dbc9dcdf 100644
--- a/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
+++ b/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
@@ -13,6 +13,10 @@
 // limitations under the License.
 
 #include "google/cloud/storage/async/options.h"
+
+// TODO(v-pratap): Remove this when EnableMD5ValidationOption and
+// EnableCrc32cValidationOption are removed.
+#include "google/cloud/internal/disable_deprecation_warnings.inc"
 #include "google/cloud/storage/internal/async/connection_impl.h"
 #include "google/cloud/storage/internal/async/default_options.h"
 #include "google/cloud/storage/internal/crc32c.h"
@@ -496,3 +500,4 @@ GOOGLE_CLOUD_CPP_INLINE_NAMESPACE_END
 }  // namespace storage_internal
 }  // namespace cloud
 }  // namespace google
+#include "google/cloud/internal/diagnostics_pop.inc"
diff --git a/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc b/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
index ae8b3e6a2318e..18fd11a459adf 100644
--- a/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
+++ b/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
@@ -13,6 +13,10 @@
 // limitations under the License.
 
 #include "google/cloud/storage/async/options.h"
+
+// TODO(v-pratap): Remove this when EnableMD5ValidationOption and
+// EnableCrc32cValidationOption are removed.
+#include "google/cloud/internal/disable_deprecation_warnings.inc"
 #include "google/cloud/storage/async/writer_connection.h"
 #include "google/cloud/storage/internal/async/connection_impl.h"
 #include "google/cloud/storage/internal/async/default_options.h"
@@ -795,3 +799,4 @@ GOOGLE_CLOUD_CPP_INLINE_NAMESPACE_END
 }  // namespace storage_internal
 }  // namespace cloud
 }  // namespace google
+#include "google/cloud/internal/diagnostics_pop.inc"
diff --git a/google/cloud/storage/internal/async/default_options_test.cc b/google/cloud/storage/internal/async/default_options_test.cc
index dc7e4e8588be8..7bdc79553a84b 100644
--- a/google/cloud/storage/internal/async/default_options_test.cc
+++ b/google/cloud/storage/internal/async/default_options_test.cc
@@ -13,6 +13,10 @@
 // limitations under the License.
 
 #include "google/cloud/storage/internal/async/default_options.h"
+
+// TODO(v-pratap): Remove this when EnableMD5ValidationOption and
+// EnableCrc32cValidationOption are removed.
+#include "google/cloud/internal/disable_deprecation_warnings.inc"
 #include "google/cloud/storage/async/idempotency_policy.h"
 #include "google/cloud/storage/async/options.h"
 #include "google/cloud/storage/async/resume_policy.h"
@@ -110,3 +114,4 @@ GOOGLE_CLOUD_CPP_INLINE_NAMESPACE_END
 }  // namespace storage_internal
 }  // namespace cloud
 }  // namespace google
+#include "google/cloud/internal/diagnostics_pop.inc"
diff --git a/google/cloud/storage/internal/async/object_descriptor_impl_test.cc b/google/cloud/storage/internal/async/object_descriptor_impl_test.cc
index 68169ed48d8a6..07830a3e63fdb 100644
--- a/google/cloud/storage/internal/async/object_descriptor_impl_test.cc
+++ b/google/cloud/storage/internal/async/object_descriptor_impl_test.cc
@@ -13,6 +13,10 @@
 // limitations under the License.
 
 #include "google/cloud/storage/internal/async/object_descriptor_impl.h"
+
+// TODO(v-pratap): Remove this when EnableMD5ValidationOption and
+// EnableCrc32cValidationOption are removed.
+#include "google/cloud/internal/disable_deprecation_warnings.inc"
 #include "google/cloud/mocks/mock_async_streaming_read_write_rpc.h"
 #include "google/cloud/storage/async/options.h"
 #include "google/cloud/storage/async/resume_policy.h"
@@ -2299,3 +2303,4 @@ GOOGLE_CLOUD_CPP_INLINE_NAMESPACE_END
 }  // namespace storage_internal
 }  // namespace cloud
 }  // namespace google
+#include "google/cloud/internal/diagnostics_pop.inc"

From e2c354a48dabdf5a33a51630d95bf421399df656 Mon Sep 17 00:00:00 2001
From: Vaibhav Pratap <vaibhavpratap85@gmail.com>
Date: Fri, 17 Jul 2026 10:42:36 +0000
Subject: [PATCH 11/12] fix(storage): fix alphabetical order in
 google_cloud_cpp_storage_grpc.bzl

---
 google/cloud/storage/google_cloud_cpp_storage_grpc.bzl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/google/cloud/storage/google_cloud_cpp_storage_grpc.bzl b/google/cloud/storage/google_cloud_cpp_storage_grpc.bzl
index 6c1ad25a15247..ad210011ea06f 100644
--- a/google/cloud/storage/google_cloud_cpp_storage_grpc.bzl
+++ b/google/cloud/storage/google_cloud_cpp_storage_grpc.bzl
@@ -37,8 +37,8 @@ google_cloud_cpp_storage_grpc_hdrs = [
     "async/writer.h",
     "async/writer_connection.h",
     "grpc_plugin.h",
-    "internal/async/connection_fwd.h",
     "internal/async/checksum_helpers.h",
+    "internal/async/connection_fwd.h",
     "internal/async/connection_impl.h",
     "internal/async/connection_tracing.h",
     "internal/async/default_options.h",

From 228b08383f49d29334497f79dfe53f075a5dca90 Mon Sep 17 00:00:00 2001
From: Vaibhav Pratap <vaibhavpratap85@gmail.com>
Date: Mon, 20 Jul 2026 07:31:58 +0000
Subject: [PATCH 12/12] test(storage): retain legacy checksum option test cases

---
 .../async/connection_impl_read_hash_test.cc   | 27 +++++++++++++++++++
 .../async/connection_impl_upload_hash_test.cc |  6 +++++
 2 files changed, 33 insertions(+)

diff --git a/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc b/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
index 35ad8dbc9dcdf..3c18df70bdb42 100644
--- a/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
+++ b/google/cloud/storage/internal/async/connection_impl_read_hash_test.cc
@@ -180,6 +180,22 @@ INSTANTIATE_TEST_SUITE_P(
                      Options{}.set<storage::DownloadChecksumValidationOption>(
                          storage::ChecksumAlgorithm::kNone),
                      kQuickFoxCrc32cChecksumBad, kQuickFoxMD5HashBad},
+        // Legacy options
+        HashTestCase{StatusCode::kOk,
+                     Options{}
+                         .set<storage::EnableCrc32cValidationOption>(true)
+                         .set<storage::EnableMD5ValidationOption>(false),
+                     kQuickFoxCrc32cChecksum, kQuickFoxMD5HashBad},
+        HashTestCase{StatusCode::kOk,
+                     Options{}
+                         .set<storage::EnableCrc32cValidationOption>(false)
+                         .set<storage::EnableMD5ValidationOption>(true),
+                     kQuickFoxCrc32cChecksumBad, kQuickFoxMD5Hash},
+        HashTestCase{StatusCode::kOk,
+                     Options{}
+                         .set<storage::EnableCrc32cValidationOption>(false)
+                         .set<storage::EnableMD5ValidationOption>(false),
+                     kQuickFoxCrc32cChecksumBad, kQuickFoxMD5HashBad},
         // In the next three cases we verify that validation works when the
         // returned values are not correct.
         HashTestCase{StatusCode::kInvalidArgument,
@@ -203,6 +219,17 @@ INSTANTIATE_TEST_SUITE_P(
                      Options{}.set<storage::DownloadChecksumValidationOption>(
                          storage::ChecksumAlgorithm::kMD5),
                      kQuickFoxCrc32cChecksumBad, kQuickFoxMD5HashBad},
+        // Legacy options
+        HashTestCase{StatusCode::kInvalidArgument,
+                     Options{}
+                         .set<storage::EnableCrc32cValidationOption>(false)
+                         .set<storage::EnableMD5ValidationOption>(true),
+                     kQuickFoxCrc32cChecksumBad, kQuickFoxMD5HashBad},
+        HashTestCase{StatusCode::kInvalidArgument,
+                     Options{}
+                         .set<storage::EnableCrc32cValidationOption>(true)
+                         .set<storage::EnableMD5ValidationOption>(false),
+                     kQuickFoxCrc32cChecksumBad, kQuickFoxMD5HashBad},
         // The application may know what the values should be. Verify the
         // validation works correctly when the application provides correct
         // values.
diff --git a/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc b/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
index 18fd11a459adf..37d2b3a71ffaa 100644
--- a/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
+++ b/google/cloud/storage/internal/async/connection_impl_upload_hash_test.cc
@@ -134,6 +134,11 @@ INSTANTIATE_TEST_SUITE_P(
         HashTestCase{Options{}.set<storage::UploadChecksumValidationOption>(
                          storage::ChecksumAlgorithm::kCrc32c),
                      kQuickFoxCrc32cChecksum, ""},
+        // Legacy options
+        HashTestCase{Options{}
+                         .set<storage::EnableCrc32cValidationOption>(true)
+                         .set<storage::EnableMD5ValidationOption>(false),
+                     kQuickFoxCrc32cChecksum, ""},
         HashTestCase{Options{}
                          .set<storage::EnableCrc32cValidationOption>(false)
                          .set<storage::EnableMD5ValidationOption>(true),
@@ -171,6 +176,7 @@ INSTANTIATE_TEST_SUITE_P(
                     storage::ChecksumAlgorithm::kNone)
                 .set<storage::UseMD5ValueOption>(BinaryMD5(kQuickFoxMD5Hash)),
             std::nullopt, kQuickFoxMD5Hash},
+        // Legacy options
         HashTestCase{Options{}
                          .set<storage::EnableCrc32cValidationOption>(false)
                          .set<storage::EnableMD5ValidationOption>(false),