impl(v3): remove backward compatible V1 namespaces (googleapis#15894)

Author: scotthart

ci/verify_deprecated_targets/verify_deprecated_targets.cc

@@ -17,8 +17,5 @@
 
 int main() {
   std::cout << "Hello: " << google::cloud::version_string() << "\n";
-  // Verifies use of the backward-compatibility aliases: v1 and gcpcxxV1.
-  std::cout << "Hello: " << google::cloud::v1::version_string() << "\n";
-  std::cout << "Hello: " << google::cloud::gcpcxxV1::version_string() << "\n";
   return 0;
 }

doc/v3-migration-guide.md

@@ -44,6 +44,62 @@ module which can be added to your `MODULE.bazel` file as a dependency.
 
 ### Common
 
+<details>
+<summary>Removed <code>v1</code> inline namespace alias.
+</summary>
+
+The `v1` namespace should be omitted for libraries that are unversioned:
+
+- Bigtable
+- PubSub
+- Spanner
+- Storage
+
+For example, code that used to look like this:
+
+**Before:**
+
+```cpp
+
+google::cloud::v1::pubsub::Publisher publisher;
+```
+
+Should be changed to this:
+
+**After:**
+
+```cpp
+google::cloud::pubsub::Publisher publisher;
+```
+
+</details>
+
+<details>
+<summary>Removed <code>gcpcxxV1</code> inline namespace alias.
+</summary>
+
+The `gcpcxxV1` namespace should be omitted from versioned libraries. The version
+is now part of the service namespace.
+
+For example, code that used to look like this:
+
+**Before:**
+
+```cpp
+
+google::cloud::bigquery_storage_v1::gcpcxxV1::BigQueryReadClient client;
+```
+
+Should be changed to this:
+
+**After:**
+
+```cpp
+google::cloud::bigquery_storage_v1::BigQueryReadClient client;
+```
+
+</details>
+
 <details>
 <summary>Removed <code>google::cloud::grpc_utils</code> namespace and headers.
 </summary>

generator/generator_config.proto

@@ -38,11 +38,6 @@ message ServiceConfiguration {
 
   repeated string omitted_services = 8;
 
-  // If set to true generate the `gcpxxV1` alias for our inline namespace. Older
-  // versions of the generated libraries need this, but new libraries should not
-  // have it.
-  bool backwards_compatibility_namespace_alias = 9;
-
   // If all rpcs in the service have the same set of retryable status codes,
   // typically found in the service_config.json accompanying the proto files,
   // generate the ServiceNameRetryTraits struct using the provided codes.

generator/generator_config.textproto

@@ -481,7 +481,6 @@ service {
   forwarding_product_path: "google/cloud/bigquery"
   initial_copyright_year: "2021"
   omitted_services: ["BigQueryWrite"]
-  backwards_compatibility_namespace_alias: true
   retryable_status_codes: ["kUnavailable"]
   omit_streaming_updater: true
 }
@@ -2679,7 +2678,6 @@ service {
   product_path: "google/cloud/iam/credentials/v1"
   forwarding_product_path: "google/cloud/iam"
   initial_copyright_year: "2020"
-  backwards_compatibility_namespace_alias: true
   retryable_status_codes: ["kUnavailable"]
   idempotency_overrides: [
     {rpc_name: "IAMCredentials.GenerateAccessToken", idempotency: IDEMPOTENT},
@@ -2695,7 +2693,6 @@ service {
   forwarding_product_path: "google/cloud/iam"
   initial_copyright_year: "2021"
   omitted_rpcs: ["SignBlob", "SignJwt", "UpdateServiceAccount"]
-  backwards_compatibility_namespace_alias: true
   retryable_status_codes: ["kUnavailable"]
   omitted_rpcs: [
     "SignBlob(std::string const&, std::string const&)",
@@ -3698,7 +3695,6 @@ service {
   initial_copyright_year: "2021"
   service_endpoint_env_var: "GOOGLE_CLOUD_CPP_SPANNER_DEFAULT_ENDPOINT"
   emulator_endpoint_env_var: "SPANNER_EMULATOR_HOST"
-  backwards_compatibility_namespace_alias: true
   retryable_status_codes: ["kUnavailable"]
   generate_rest_transport: true
   omit_repo_metadata: true
@@ -3711,7 +3707,6 @@ service {
   initial_copyright_year: "2021"
   service_endpoint_env_var: "GOOGLE_CLOUD_CPP_SPANNER_DEFAULT_ENDPOINT"
   emulator_endpoint_env_var: "SPANNER_EMULATOR_HOST"
-  backwards_compatibility_namespace_alias: true
   retryable_status_codes: ["kUnavailable"]
   generate_rest_transport: true
   omit_repo_metadata: true

generator/internal/codegen_utils_test.cc

@@ -265,16 +265,6 @@ TEST(ProcessCommandLineArgs, ProcessArgAsyncOnlyRpc) {
               Contains(Pair("gen_async_rpcs", HasSubstr("AsyncOnly"))));
 }
 
-TEST(ProcessCommandLineArgs, ProcessArgNamespaceAlias) {
-  auto result = ProcessCommandLineArgs(
-      ",product_path=google/cloud/spanner/"
-      ",emulator_endpoint_env_var=SPANNER_EMULATOR_HOST"
-      ",backwards_compatibility_namespace_alias=true");
-  ASSERT_THAT(result, IsOk());
-  EXPECT_THAT(*result, Contains(Pair("backwards_compatibility_namespace_alias",
-                                     HasSubstr("true"))));
-}
-
 TEST(ProcessCommandLineArgs, ProcessOmitClient) {
   auto result = ProcessCommandLineArgs(
       "product_path=google/cloud/spanner/"

generator/internal/make_generators.cc

@@ -148,10 +148,7 @@ std::vector<std::unique_ptr<GeneratorInterface>> MakeGenerators(
   }
 
   if (generate_rest_transport) {
-    // All REST interfaces postdate the change to the format of our inline
-    // namespace name, so we never need to add a backwards-compatibility alias.
     auto rest_service_vars = service_vars;
-    rest_service_vars.erase("backwards_compatibility_namespace_alias");
     code_generators.push_back(std::make_unique<ConnectionRestGenerator>(
         service, rest_service_vars, method_vars, context, mixin_methods));
     code_generators.push_back(std::make_unique<ConnectionImplRestGenerator>(

generator/internal/service_code_generator.cc

@@ -72,9 +72,6 @@ ServiceCodeGenerator::ServiceCodeGenerator(
   assert(context != nullptr);
   SetVars(service_vars_[header_path_key]);
   SetMethods();
-  auto e = service_vars_.find("backwards_compatibility_namespace_alias");
-  define_backwards_compatibility_namespace_alias_ =
-      (e != service_vars_.end() && e->second == "true");
 }
 
 ServiceCodeGenerator::ServiceCodeGenerator(
@@ -324,9 +321,7 @@ Status ServiceCodeGenerator::HeaderOpenForwardingNamespaces(
                         ns_documentation);
 }
 
-void ServiceCodeGenerator::HeaderCloseNamespaces() {
-  CloseNamespaces(header_, define_backwards_compatibility_namespace_alias_);
-}
+void ServiceCodeGenerator::HeaderCloseNamespaces() { CloseNamespaces(header_); }
 
 Status ServiceCodeGenerator::CcOpenNamespaces(NamespaceType ns_type) {
   return OpenNamespaces(cc_, ns_type, "product_path");
@@ -336,7 +331,7 @@ Status ServiceCodeGenerator::CcOpenForwardingNamespaces(NamespaceType ns_type) {
   return OpenNamespaces(cc_, ns_type, "forwarding_product_path");
 }
 
-void ServiceCodeGenerator::CcCloseNamespaces() { CloseNamespaces(cc_, false); }
+void ServiceCodeGenerator::CcCloseNamespaces() { CloseNamespaces(cc_); }
 
 void ServiceCodeGenerator::HeaderPrint(std::string const& text) {
   header_.Print(service_vars_, text);
@@ -445,15 +440,9 @@ GOOGLE_CLOUD_CPP_INLINE_NAMESPACE_BEGIN
   return {};
 }
 
-void ServiceCodeGenerator::CloseNamespaces(
-    Printer& p, bool define_backwards_compatibility_namespace_alias) {
+void ServiceCodeGenerator::CloseNamespaces(Printer& p) {
   p.Print(R"""(
 GOOGLE_CLOUD_CPP_INLINE_NAMESPACE_END)""");
-  // TODO(#7463) - remove backwards compatibility namespaces
-  if (define_backwards_compatibility_namespace_alias) {
-    p.Print(R"""(
-namespace gcpcxxV1 = GOOGLE_CLOUD_CPP_NS; // NOLINT(misc-unused-alias-decls))""");
-  }
   p.Print(R"""(
 }  // namespace $namespace$
 }  // namespace cloud

generator/internal/service_code_generator.h

@@ -259,14 +259,12 @@ class ServiceCodeGenerator : public GeneratorInterface {
   Status OpenNamespaces(Printer& p, NamespaceType ns_type,
                         std::string const& product_path_var,
                         std::string const& ns_documentation = "");
-  void CloseNamespaces(Printer& p,
-                       bool define_backwards_compatibility_namespace_alias);
+  void CloseNamespaces(Printer& p);
 
   google::protobuf::ServiceDescriptor const* service_descriptor_;
   VarsDictionary service_vars_;
   std::map<std::string, VarsDictionary> service_method_vars_;
   std::string namespace_;
-  bool define_backwards_compatibility_namespace_alias_ = false;
   bool pb_h_system_includes_ = false;
   MethodDescriptorList methods_;
   MethodDescriptorList async_methods_;

generator/standalone_main.cc

@@ -289,10 +289,6 @@ std::vector<std::future<google::cloud::Status>> GenerateCodeFromProtos(
       args.emplace_back(absl::StrCat("--cpp_codegen_opt=omit_rpc=",
                                      SafeReplaceAll(omit_rpc, ",", "@")));
     }
-    if (service.backwards_compatibility_namespace_alias()) {
-      args.emplace_back(
-          "--cpp_codegen_opt=backwards_compatibility_namespace_alias=true");
-    }
     for (auto const& retry_code : service.retryable_status_codes()) {
       args.emplace_back("--cpp_codegen_opt=retry_status_code=" + retry_code);
     }

google/cloud/bigquery/storage/v1/bigquery_read_client.h

@@ -315,7 +315,6 @@ class BigQueryReadClient {
 };
 
 GOOGLE_CLOUD_CPP_INLINE_NAMESPACE_END
-namespace gcpcxxV1 = GOOGLE_CLOUD_CPP_NS;  // NOLINT(misc-unused-alias-decls)
 }  // namespace bigquery_storage_v1
 }  // namespace cloud
 }  // namespace google