[generic API] separate callback from cq in generic stub/service

BUILD

@@ -430,7 +430,9 @@ GRPCXX_PUBLIC_HDRS = [
     "include/grpcpp/create_channel_posix.h",
     "include/grpcpp/ext/health_check_service_server_builder_option.h",
     "include/grpcpp/generic/async_generic_service.h",
+    "include/grpcpp/generic/callback_generic_service.h",
     "include/grpcpp/generic/generic_stub.h",
+    "include/grpcpp/generic/generic_stub_callback.h",
     "include/grpcpp/grpcpp.h",
     "include/grpcpp/health_check_service_interface.h",
     "include/grpcpp/impl/call_hook.h",
@@ -1269,6 +1271,7 @@ grpc_cc_library(
     visibility = ["@grpc:public"],
     deps = [
         "channel_arg_names",
+        "generic_stub_internal",
         "gpr",
         "grpc++_base_unsecure",
         "grpc++_codegen_proto",
@@ -2506,6 +2509,7 @@ grpc_cc_library(
         "channel_stack_builder",
         "config",
         "exec_ctx",
+        "generic_stub_internal",
         "gpr",
         "grpc",
         "grpc++_codegen_proto",
@@ -2593,6 +2597,7 @@ grpc_cc_library(
         "channel_stack_builder",
         "config",
         "exec_ctx",
+        "generic_stub_internal",
         "gpr",
         "grpc_base",
         "grpc_core_credentials_header",
@@ -2991,6 +2996,41 @@ grpc_cc_library(
     ],
 )
 
+grpc_cc_library(
+    name = "generic_stub_internal",
+    hdrs = [
+        "include/grpcpp/impl/generic_stub_internal.h",
+    ],
+    language = "c++",
+    deps = [
+        "grpc++_public_hdrs",
+    ],
+)
+
+grpc_cc_library(
+    name = "generic_stub_callback",
+    hdrs = [
+        "include/grpcpp/generic/generic_stub_callback.h",
+    ],
+    language = "c++",
+    visibility = ["@grpc:public"],
+    deps = [
+        "generic_stub_internal",
+    ],
+)
+
+grpc_cc_library(
+    name = "callback_generic_service",
+    hdrs = [
+        "include/grpcpp/generic/callback_generic_service.h",
+    ],
+    language = "c++",
+    visibility = ["@grpc:public"],
+    deps = [
+        "grpc++_public_hdrs",
+    ],
+)
+
 grpc_cc_library(
     name = "work_serializer",
     srcs = [

include/grpcpp/generic/async_generic_service.h

@@ -20,10 +20,9 @@
 #define GRPCPP_GENERIC_ASYNC_GENERIC_SERVICE_H
 
 #include <grpc/support/port_platform.h>
-#include <grpcpp/impl/server_callback_handlers.h>
+#include <grpcpp/generic/callback_generic_service.h>
 #include <grpcpp/support/async_stream.h>
 #include <grpcpp/support/byte_buffer.h>
-#include <grpcpp/support/server_callback.h>
 
 struct grpc_server;
 
@@ -78,57 +77,6 @@ class AsyncGenericService final {
   grpc::Server* server_;
 };
 
-/// \a ServerGenericBidiReactor is the reactor class for bidi streaming RPCs
-/// invoked on a CallbackGenericService. It is just a ServerBidi reactor with
-/// ByteBuffer arguments.
-using ServerGenericBidiReactor = ServerBidiReactor<ByteBuffer, ByteBuffer>;
-
-class GenericCallbackServerContext final : public grpc::CallbackServerContext {
- public:
-  const std::string& method() const { return method_; }
-  const std::string& host() const { return host_; }
-
- private:
-  friend class grpc::Server;
-
-  std::string method_;
-  std::string host_;
-};
-
-/// \a CallbackGenericService is the base class for generic services implemented
-/// using the callback API and registered through the ServerBuilder using
-/// RegisterCallbackGenericService.
-class CallbackGenericService {
- public:
-  CallbackGenericService() {}
-  virtual ~CallbackGenericService() {}
-
-  /// The "method handler" for the generic API. This function should be
-  /// overridden to provide a ServerGenericBidiReactor that implements the
-  /// application-level interface for this RPC. Unimplemented by default.
-  virtual ServerGenericBidiReactor* CreateReactor(
-      GenericCallbackServerContext* /*ctx*/) {
-    class Reactor : public ServerGenericBidiReactor {
-     public:
-      Reactor() { this->Finish(Status(StatusCode::UNIMPLEMENTED, "")); }
-      void OnDone() override { delete this; }
-    };
-    return new Reactor;
-  }
-
- private:
-  friend class grpc::Server;
-
-  internal::CallbackBidiHandler<ByteBuffer, ByteBuffer>* Handler() {
-    return new internal::CallbackBidiHandler<ByteBuffer, ByteBuffer>(
-        [this](grpc::CallbackServerContext* ctx) {
-          return CreateReactor(static_cast<GenericCallbackServerContext*>(ctx));
-        });
-  }
-
-  grpc::Server* server_{nullptr};
-};
-
 }  // namespace grpc
 
 #endif  // GRPCPP_GENERIC_ASYNC_GENERIC_SERVICE_H

include/grpcpp/generic/callback_generic_service.h

@@ -0,0 +1,84 @@
+//
+//
+// Copyright 2024 gRPC authors.
+//
+// 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
+//
+//     http://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 GRPCPP_GENERIC_CALLBACK_GENERIC_SERVICE_H
+#define GRPCPP_GENERIC_CALLBACK_GENERIC_SERVICE_H
+
+#include <grpc/support/port_platform.h>
+#include <grpcpp/impl/server_callback_handlers.h>
+#include <grpcpp/support/byte_buffer.h>
+#include <grpcpp/support/server_callback.h>
+
+struct grpc_server;
+
+namespace grpc {
+
+/// \a ServerGenericBidiReactor is the reactor class for bidi streaming RPCs
+/// invoked on a CallbackGenericService. It is just a ServerBidi reactor with
+/// ByteBuffer arguments.
+using ServerGenericBidiReactor = ServerBidiReactor<ByteBuffer, ByteBuffer>;
+
+class GenericCallbackServerContext final : public grpc::CallbackServerContext {
+ public:
+  const std::string& method() const { return method_; }
+  const std::string& host() const { return host_; }
+
+ private:
+  friend class grpc::Server;
+
+  std::string method_;
+  std::string host_;
+};
+
+/// \a CallbackGenericService is the base class for generic services implemented
+/// using the callback API and registered through the ServerBuilder using
+/// RegisterCallbackGenericService.
+class CallbackGenericService {
+ public:
+  CallbackGenericService() {}
+  virtual ~CallbackGenericService() {}
+
+  /// The "method handler" for the generic API. This function should be
+  /// overridden to provide a ServerGenericBidiReactor that implements the
+  /// application-level interface for this RPC. Unimplemented by default.
+  virtual ServerGenericBidiReactor* CreateReactor(
+      GenericCallbackServerContext* /*ctx*/) {
+    class Reactor : public ServerGenericBidiReactor {
+     public:
+      Reactor() { this->Finish(Status(StatusCode::UNIMPLEMENTED, "")); }
+      void OnDone() override { delete this; }
+    };
+    return new Reactor;
+  }
+
+ private:
+  friend class grpc::Server;
+
+  internal::CallbackBidiHandler<ByteBuffer, ByteBuffer>* Handler() {
+    return new internal::CallbackBidiHandler<ByteBuffer, ByteBuffer>(
+        [this](grpc::CallbackServerContext* ctx) {
+          return CreateReactor(static_cast<GenericCallbackServerContext*>(ctx));
+        });
+  }
+
+  grpc::Server* server_{nullptr};
+};
+
+}  // namespace grpc
+
+#endif  // GRPCPP_GENERIC_CALLBACK_GENERIC_SERVICE_H