Mixin draft lite

generator/CMakeLists.txt

@@ -96,6 +96,8 @@ add_library(
     internal/metadata_decorator_generator.h
     internal/metadata_decorator_rest_generator.cc
     internal/metadata_decorator_rest_generator.h
+    internal/mixin_utils.cc
+    internal/mixin_utils.h
     internal/mock_connection_generator.cc
     internal/mock_connection_generator.h
     internal/option_defaults_generator.cc

generator/google_cloud_cpp_generator.bzl

@@ -50,6 +50,7 @@ google_cloud_cpp_generator_hdrs = [
     "internal/make_generators.h",
     "internal/metadata_decorator_generator.h",
     "internal/metadata_decorator_rest_generator.h",
+    "internal/mixin_utils.h",
     "internal/mock_connection_generator.h",
     "internal/option_defaults_generator.h",
     "internal/options_generator.h",
@@ -108,6 +109,7 @@ google_cloud_cpp_generator_srcs = [
     "internal/make_generators.cc",
     "internal/metadata_decorator_generator.cc",
     "internal/metadata_decorator_rest_generator.cc",
+    "internal/mixin_utils.cc",
     "internal/mock_connection_generator.cc",
     "internal/option_defaults_generator.cc",
     "internal/options_generator.cc",

generator/integration_tests/golden/v1/internal/golden_kitchen_sink_stub.h

@@ -129,7 +129,7 @@ class DefaultGoldenKitchenSinkStub : public GoldenKitchenSinkStub {
  public:
   explicit DefaultGoldenKitchenSinkStub(
       std::unique_ptr<google::test::admin::database::v1::GoldenKitchenSink::StubInterface> grpc_stub)
-      : grpc_stub_(std::move(grpc_stub)) {}
+      : grpc_stub_(std::move(grpc_stub)){}
 
   StatusOr<google::test::admin::database::v1::GenerateAccessTokenResponse> GenerateAccessToken(
       grpc::ClientContext& context,

generator/integration_tests/golden/v1/internal/golden_thing_admin_stub.h

@@ -189,10 +189,10 @@ class GoldenThingAdminStub {
 class DefaultGoldenThingAdminStub : public GoldenThingAdminStub {
  public:
   DefaultGoldenThingAdminStub(
-      std::unique_ptr<google::test::admin::database::v1::GoldenThingAdmin::StubInterface> grpc_stub,
-      std::unique_ptr<google::longrunning::Operations::StubInterface> operations)
-      : grpc_stub_(std::move(grpc_stub)),
-        operations_(std::move(operations)) {}
+      std::unique_ptr<google::test::admin::database::v1::GoldenThingAdmin::StubInterface> grpc_stub
+      ,std::unique_ptr<google::longrunning::Operations::StubInterface> operations)
+      : grpc_stub_(std::move(grpc_stub))
+        , operations_(std::move(operations)) {}
 
   StatusOr<google::test::admin::database::v1::ListDatabasesResponse> ListDatabases(
       grpc::ClientContext& context,

generator/integration_tests/golden/v1/internal/request_id_stub.h

@@ -82,10 +82,10 @@ class RequestIdServiceStub {
 class DefaultRequestIdServiceStub : public RequestIdServiceStub {
  public:
   DefaultRequestIdServiceStub(
-      std::unique_ptr<google::test::requestid::v1::RequestIdService::StubInterface> grpc_stub,
-      std::unique_ptr<google::longrunning::Operations::StubInterface> operations)
-      : grpc_stub_(std::move(grpc_stub)),
-        operations_(std::move(operations)) {}
+      std::unique_ptr<google::test::requestid::v1::RequestIdService::StubInterface> grpc_stub
+      ,std::unique_ptr<google::longrunning::Operations::StubInterface> operations)
+      : grpc_stub_(std::move(grpc_stub))
+        , operations_(std::move(operations)) {}
 
   StatusOr<google::test::requestid::v1::Foo> CreateFoo(
       grpc::ClientContext& context,

generator/internal/auth_decorator_generator.cc

@@ -28,10 +28,11 @@ AuthDecoratorGenerator::AuthDecoratorGenerator(
     google::protobuf::ServiceDescriptor const* service_descriptor,
     VarsDictionary service_vars,
     std::map<std::string, VarsDictionary> service_method_vars,
-    google::protobuf::compiler::GeneratorContext* context)
+    google::protobuf::compiler::GeneratorContext* context,
+    std::vector<MixinMethod> const& mixin_methods)
     : StubGeneratorBase("auth_header_path", "auth_cc_path", service_descriptor,
                         std::move(service_vars), std::move(service_method_vars),
-                        context) {}
+                        context, mixin_methods) {}
 
 Status AuthDecoratorGenerator::GenerateHeader() {
   HeaderPrint(CopyrightLicenseFileHeader());

generator/internal/auth_decorator_generator.h

@@ -37,7 +37,8 @@ class AuthDecoratorGenerator : public StubGeneratorBase {
       google::protobuf::ServiceDescriptor const* service_descriptor,
       VarsDictionary service_vars,
       std::map<std::string, VarsDictionary> service_method_vars,
-      google::protobuf::compiler::GeneratorContext* context);
+      google::protobuf::compiler::GeneratorContext* context,
+      std::vector<MixinMethod> const& mixin_methods);
 
   ~AuthDecoratorGenerator() override = default;
 

generator/internal/client_generator.cc

@@ -32,10 +32,12 @@ ClientGenerator::ClientGenerator(
     google::protobuf::ServiceDescriptor const* service_descriptor,
     VarsDictionary service_vars,
     std::map<std::string, VarsDictionary> service_method_vars,
-    google::protobuf::compiler::GeneratorContext* context)
+    google::protobuf::compiler::GeneratorContext* context,
+    std::vector<MixinMethod> const& mixin_methods)
     : ServiceCodeGenerator("client_header_path", "client_cc_path",
                            service_descriptor, std::move(service_vars),
-                           std::move(service_method_vars), context) {
+                           std::move(service_method_vars), context,
+                           mixin_methods) {
   // Remember if there are methods from google.iam.v1.GetIamPolicyRequest and
   // google.iam.v1.SetIamPolicyRequest to google.iam.v1.Policy with signature
   // extensions. If so, we'll generate a "set" wrapper method to help prevent

generator/internal/client_generator.h

@@ -36,7 +36,8 @@ class ClientGenerator : public ServiceCodeGenerator {
   ClientGenerator(google::protobuf::ServiceDescriptor const* service_descriptor,
                   VarsDictionary service_vars,
                   std::map<std::string, VarsDictionary> service_method_vars,
-                  google::protobuf::compiler::GeneratorContext* context);
+                  google::protobuf::compiler::GeneratorContext* context,
+                  std::vector<MixinMethod> const& mixin_methods);
 
   ~ClientGenerator() override = default;
 

generator/internal/connection_generator.cc

@@ -19,6 +19,7 @@
 #include "generator/internal/pagination.h"
 #include "generator/internal/predicate_utils.h"
 #include "generator/internal/printer.h"
+#include "absl/strings/str_split.h"
 #include <google/protobuf/descriptor.h>
 
 namespace google {
@@ -29,10 +30,12 @@ ConnectionGenerator::ConnectionGenerator(
     google::protobuf::ServiceDescriptor const* service_descriptor,
     VarsDictionary service_vars,
     std::map<std::string, VarsDictionary> service_method_vars,
-    google::protobuf::compiler::GeneratorContext* context)
+    google::protobuf::compiler::GeneratorContext* context,
+    std::vector<MixinMethod> const& mixin_methods)
     : ServiceCodeGenerator("connection_header_path", "connection_cc_path",
                            service_descriptor, std::move(service_vars),
-                           std::move(service_method_vars), context) {}
+                           std::move(service_method_vars), context,
+                           mixin_methods) {}
 
 Status ConnectionGenerator::GenerateHeader() {
   HeaderPrint(CopyrightLicenseFileHeader());
@@ -68,11 +71,14 @@ Status ConnectionGenerator::GenerateHeader() {
            : "",
        IsExperimental() ? "google/cloud/experimental_tag.h" : "",
        "google/cloud/version.h"});
-  HeaderSystemIncludes(
-      {vars("proto_header_path"), vars("additional_pb_header_paths"),
-       HasGRPCLongrunningOperation() ? "google/longrunning/operations.grpc.pb.h"
-                                     : "",
-       "memory"});
+  std::vector<std::string> const additional_pb_header_paths =
+      absl::StrSplit(vars("additional_pb_header_paths"), absl::ByChar(','));
+  HeaderSystemIncludes(additional_pb_header_paths);
+  HeaderSystemIncludes({vars("proto_header_path"),
+                        HasGRPCLongrunningOperation()
+                            ? "google/longrunning/operations.grpc.pb.h"
+                            : "",
+                        "memory"});
   switch (endpoint_location_style) {
     case ServiceConfiguration::LOCATION_DEPENDENT:
     case ServiceConfiguration::LOCATION_DEPENDENT_COMPAT:

generator/internal/connection_generator.h

@@ -38,7 +38,8 @@ class ConnectionGenerator : public ServiceCodeGenerator {
       google::protobuf::ServiceDescriptor const* service_descriptor,
       VarsDictionary service_vars,
       std::map<std::string, VarsDictionary> service_method_vars,
-      google::protobuf::compiler::GeneratorContext* context);
+      google::protobuf::compiler::GeneratorContext* context,
+      std::vector<MixinMethod> const& mixin_methods);
 
   ~ConnectionGenerator() override = default;
 

generator/internal/connection_impl_generator.cc

@@ -38,11 +38,12 @@ ConnectionImplGenerator::ConnectionImplGenerator(
     google::protobuf::ServiceDescriptor const* service_descriptor,
     VarsDictionary service_vars,
     std::map<std::string, VarsDictionary> service_method_vars,
-    google::protobuf::compiler::GeneratorContext* context)
-    : ServiceCodeGenerator("connection_impl_header_path",
-                           "connection_impl_cc_path", service_descriptor,
-                           std::move(service_vars),
-                           std::move(service_method_vars), context) {}
+    google::protobuf::compiler::GeneratorContext* context,
+    std::vector<MixinMethod> const& mixin_methods)
+    : ServiceCodeGenerator(
+          "connection_impl_header_path", "connection_impl_cc_path",
+          service_descriptor, std::move(service_vars),
+          std::move(service_method_vars), context, mixin_methods) {}
 
 Status ConnectionImplGenerator::GenerateHeader() {
   HeaderPrint(CopyrightLicenseFileHeader());

generator/internal/connection_impl_generator.h

@@ -38,7 +38,8 @@ class ConnectionImplGenerator : public ServiceCodeGenerator {
       google::protobuf::ServiceDescriptor const* service_descriptor,
       VarsDictionary service_vars,
       std::map<std::string, VarsDictionary> service_method_vars,
-      google::protobuf::compiler::GeneratorContext* context);
+      google::protobuf::compiler::GeneratorContext* context,
+      std::vector<MixinMethod> const& mixin_methods);
 
   ~ConnectionImplGenerator() override = default;
 

generator/internal/connection_impl_rest_generator.cc

@@ -30,11 +30,12 @@ ConnectionImplRestGenerator::ConnectionImplRestGenerator(
     google::protobuf::ServiceDescriptor const* service_descriptor,
     VarsDictionary service_vars,
     std::map<std::string, VarsDictionary> service_method_vars,
-    google::protobuf::compiler::GeneratorContext* context)
-    : ServiceCodeGenerator("connection_impl_rest_header_path",
-                           "connection_impl_rest_cc_path", service_descriptor,
-                           std::move(service_vars),
-                           std::move(service_method_vars), context) {}
+    google::protobuf::compiler::GeneratorContext* context,
+    std::vector<MixinMethod> const& mixin_methods)
+    : ServiceCodeGenerator(
+          "connection_impl_rest_header_path", "connection_impl_rest_cc_path",
+          service_descriptor, std::move(service_vars),
+          std::move(service_method_vars), context, mixin_methods) {}
 
 Status ConnectionImplRestGenerator::GenerateHeader() {
   HeaderPrint(CopyrightLicenseFileHeader());

generator/internal/connection_impl_rest_generator.h

@@ -38,7 +38,8 @@ class ConnectionImplRestGenerator : public ServiceCodeGenerator {
       google::protobuf::ServiceDescriptor const* service_descriptor,
       VarsDictionary service_vars,
       std::map<std::string, VarsDictionary> service_method_vars,
-      google::protobuf::compiler::GeneratorContext* context);
+      google::protobuf::compiler::GeneratorContext* context,
+      std::vector<MixinMethod> const& mixin_methods);
 
   ~ConnectionImplRestGenerator() override = default;
 

generator/internal/connection_rest_generator.cc

@@ -27,11 +27,12 @@ ConnectionRestGenerator::ConnectionRestGenerator(
     google::protobuf::ServiceDescriptor const* service_descriptor,
     VarsDictionary service_vars,
     std::map<std::string, VarsDictionary> service_method_vars,
-    google::protobuf::compiler::GeneratorContext* context)
-    : ServiceCodeGenerator("connection_rest_header_path",
-                           "connection_rest_cc_path", service_descriptor,
-                           std::move(service_vars),
-                           std::move(service_method_vars), context) {}
+    google::protobuf::compiler::GeneratorContext* context,
+    std::vector<MixinMethod> const& mixin_methods)
+    : ServiceCodeGenerator(
+          "connection_rest_header_path", "connection_rest_cc_path",
+          service_descriptor, std::move(service_vars),
+          std::move(service_method_vars), context, mixin_methods) {}
 
 Status ConnectionRestGenerator::GenerateHeader() {
   HeaderPrint(CopyrightLicenseFileHeader());

generator/internal/connection_rest_generator.h

@@ -38,7 +38,8 @@ class ConnectionRestGenerator : public ServiceCodeGenerator {
       google::protobuf::ServiceDescriptor const* service_descriptor,
       VarsDictionary service_vars,
       std::map<std::string, VarsDictionary> service_method_vars,
-      google::protobuf::compiler::GeneratorContext* context);
+      google::protobuf::compiler::GeneratorContext* context,
+      std::vector<MixinMethod> const& mixin_methods);
 
   ~ConnectionRestGenerator() override = default;
 

generator/internal/descriptor_utils.cc

@@ -455,6 +455,18 @@ std::string FormatAdditionalPbHeaderPaths(VarsDictionary& vars) {
   return absl::StrJoin(additional_pb_header_paths, ",");
 }
 
+std::string FormatMixinPbHeaderPaths(
+    std::vector<MixinMethod> const& mixin_methods, std::string suffix) {
+  std::vector<std::string> mixin_header_paths;
+  for (auto const& mixin_method : mixin_methods) {
+    std::string mixin_header_path = absl::StrCat(
+        absl::StripSuffix(mixin_method.method.get().file()->name(), ".proto"),
+        suffix);
+    mixin_header_paths.push_back(mixin_header_path);
+  }
+  return absl::StrJoin(mixin_header_paths, ",");
+}
+
 // If a service name mapping exists, return the new name.
 // Parses a command line argument in the form:
 // {"service_name_mappings": "service_a=new_service_a,service=new_service"}.
@@ -559,7 +571,8 @@ bool CheckParameterCommentSubstitutions() {
 
 VarsDictionary CreateServiceVars(
     google::protobuf::ServiceDescriptor const& descriptor,
-    std::vector<std::pair<std::string, std::string>> const& initial_values) {
+    std::vector<std::pair<std::string, std::string>> const& initial_values,
+    std::vector<MixinMethod> const& mixin_methods) {
   VarsDictionary vars(initial_values.begin(), initial_values.end());
   auto const& service_name = GetEffectiveServiceName(vars, descriptor.name());
   vars["product_options_page"] = OptionsGroup(vars["product_path"]);
@@ -692,6 +705,10 @@ VarsDictionary CreateServiceVars(
       absl::StripSuffix(descriptor.file()->name(), ".proto"), ".grpc.pb.h");
   vars["proto_header_path"] = absl::StrCat(
       absl::StripSuffix(descriptor.file()->name(), ".proto"), ".pb.h");
+  vars["mixin_proto_grpc_header_paths"] =
+      FormatMixinPbHeaderPaths(mixin_methods, ".grpc.pb.h");
+  vars["mixin_proto_header_paths"] =
+      FormatMixinPbHeaderPaths(mixin_methods, ".pb.h");
   vars["retry_policy_name"] = absl::StrCat(service_name, "RetryPolicy");
   vars["retry_traits_name"] = absl::StrCat(service_name, "RetryTraits");
   vars["retry_traits_header_path"] =
@@ -802,7 +819,8 @@ std::map<std::string, std::string> ParseIdempotencyOverrides(
 
 std::map<std::string, VarsDictionary> CreateMethodVars(
     google::protobuf::ServiceDescriptor const& service,
-    YAML::Node const& service_config, VarsDictionary const& vars) {
+    YAML::Node const& service_config, VarsDictionary const& vars,
+    std::vector<MixinMethod> const& mixin_methods) {
   auto split_arg = [&vars](std::string const& arg) -> std::set<std::string> {
     auto l = vars.find(arg);
     if (l == vars.end()) return {};
@@ -842,7 +860,46 @@ std::map<std::string, VarsDictionary> CreateMethodVars(
     SetLongrunningOperationMethodVars(method, method_vars);
     AssignPaginationMethodVars(method, method_vars);
     SetMethodSignatureMethodVars(service, method, omitted_rpcs, method_vars);
-    auto parsed_http_info = ParseHttpExtension(method);
+    auto parsed_http_info = ParseHttpExtension(method, service);
+    method_vars["request_resource"] =
+        FormatRequestResource(*method.input_type(), parsed_http_info);
+    SetHttpDerivedMethodVars(parsed_http_info, method, method_vars);
+    SetHttpQueryParameters(parsed_http_info, method, method_vars);
+    service_methods_vars[method.full_name()] = method_vars;
+  }
+  for (auto const& mixin_method : mixin_methods) {
+    auto const& method = mixin_method.method.get();
+    VarsDictionary method_vars;
+    method_vars["method_return_doxygen_link"] =
+        FormatDoxygenLink(*method.output_type());
+    method_vars["idempotency"] = DefaultIdempotencyFromHttpOperation(method);
+    if (!idempotency_overrides.empty()) {
+      auto iter = idempotency_overrides.find(
+          absl::StrCat(service.name(), ".", method.name()));
+      if (iter != idempotency_overrides.end()) {
+        method_vars["idempotency"] = iter->second;
+      }
+    }
+    method_vars["method_name"] = method.name();
+    method_vars["method_name_snake"] = CamelCaseToSnakeCase(method.name());
+    method_vars["request_type"] =
+        ProtoNameToCppName(method.input_type()->full_name());
+    method_vars["response_message_type"] = method.output_type()->full_name();
+    method_vars["response_type"] =
+        ProtoNameToCppName(method.output_type()->full_name());
+    method_vars["return_type"] =
+        IsResponseTypeEmpty(method)
+            ? "Status"
+            : absl::StrFormat("StatusOr<%s>", method_vars.at("response_type"));
+    auto request_id_field_name = RequestIdFieldName(service_config, method);
+    if (!request_id_field_name.empty()) {
+      method_vars["request_id_field_name"] = std::move(request_id_field_name);
+    }
+    SetLongrunningOperationMethodVars(method, method_vars);
+    AssignPaginationMethodVars(method, method_vars);
+    SetMethodSignatureMethodVars(service, method, omitted_rpcs, method_vars);
+    auto parsed_http_info =
+        ParseHttpExtension(method, service, mixin_method.method_override);
     method_vars["request_resource"] =
         FormatRequestResource(*method.input_type(), parsed_http_info);
     SetHttpDerivedMethodVars(parsed_http_info, method, method_vars);

generator/internal/descriptor_utils.h

@@ -16,6 +16,7 @@
 #define GOOGLE_CLOUD_CPP_GENERATOR_INTERNAL_DESCRIPTOR_UTILS_H
 
 #include "generator/internal/generator_interface.h"
+#include "generator/internal/mixin_utils.h"
 #include "generator/internal/predicate_utils.h"
 #include "generator/internal/printer.h"
 #include "absl/types/variant.h"
@@ -38,14 +39,16 @@ namespace generator_internal {
  */
 VarsDictionary CreateServiceVars(
     google::protobuf::ServiceDescriptor const& descriptor,
-    std::vector<std::pair<std::string, std::string>> const& initial_values);
+    std::vector<std::pair<std::string, std::string>> const& initial_values,
+    std::vector<MixinMethod> const& mixin_methods = std::vector<MixinMethod>());
 
 /**
  * Extracts method specific substitution data for each method in the service.
  */
 std::map<std::string, VarsDictionary> CreateMethodVars(
     google::protobuf::ServiceDescriptor const& service,
-    YAML::Node const& service_config, VarsDictionary const& service_vars);
+    YAML::Node const& service_config, VarsDictionary const& service_vars,
+    std::vector<MixinMethod> const& mixin_methods = std::vector<MixinMethod>());
 
 /**
  * Determines which `MethodPattern` to use from patterns for the given method