From 4dda2db5a1b7fab7ab819427ec6edc984dae8a61 Mon Sep 17 00:00:00 2001
From: Tao He <sighingnow@gmail.com>
Date: Thu, 27 May 2021 23:13:04 +0800
Subject: [PATCH] Compatible with older version of gRPC.

Signed-off-by: Tao He <sighingnow@gmail.com>
---
 CMakeLists.txt  | 23 +++++++++++++++++++++--
 etcd/Client.hpp | 10 ++++++++++
 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ae5f1ac..f631527 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -10,6 +10,7 @@ set(etcd-cpp-api_VERSION ${etcd-cpp-api_VERSION_MAJOR}.${etcd-cpp-api_VERSION_MI
 set(CMAKE_PROJECT_HOMEPAGE_URL https://github.com/etcd-cpp-apiv3/etcd-cpp-apiv3)
 
 include(CheckCXXCompilerFlag)
+include(CheckCXXSourceCompiles)
 include(CheckLibraryExists)
 include(GNUInstallDirs)
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
@@ -86,6 +87,19 @@ if(NOT CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wpedantic -Werror -Wno-string-compare -std=c++11")
 endif()
 
+message("GRPC_INCLUDE_DIR = ${gRPC_FOUND}")
+set(CMAKE_REQUIRED_INCLUDES "${CMAKE_REQUIRED_INCLUDES} ${GRPC_INCLUDE_DIR}")
+set(CMAKE_REQUIRED_LIBRARIES "${CMAKE_REQUIRED_LIBRARIES} ${GRPC_LIBRARIES}")
+set(CMAKE_REQUIRED_DEFINITIONS "${CMAKE_REQUIRED_DEFINITIONS}")
+check_cxx_source_compiles("
+#include <grpc++/grpc++.h>
+namespace grpc { class Channel; }
+int main() {}
+" GRPC_CHANNEL_CLASS_FOUND)
+if(GRPC_CHANNEL_CLASS_FOUND)
+    add_definitions(-DWITH_GRPC_CHANNEL_CLASS)
+endif()
+
 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${PROJECT_BINARY_DIR}/bin)
 
 enable_testing()
@@ -185,5 +199,10 @@ set(CPACK_DEBIAN_PACKAGE_DISTRIBUTION "focal")
 set(DPUT_HOST "ppa:graphscope/etcd-cpp-api")
 set(DPUT_SNAPSHOT_HOST "ppa:graphscope/etcd-cpp-api")
 
-list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
-include(UploadPPA)
+find_program(DEBUILD_EXECUTABLE debuild)
+find_program(DPUT_EXECUTABLE dput)
+
+if(DEBUILD_EXECUTABLE AND DPUT_EXECUTABLE)
+    list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
+    include(UploadPPA)
+endif()
diff --git a/etcd/Client.hpp b/etcd/Client.hpp
index 8222bff..219cd2f 100644
--- a/etcd/Client.hpp
+++ b/etcd/Client.hpp
@@ -17,9 +17,15 @@ namespace etcdv3 {
   }
 }
 
+#if defined(WITH_GRPC_CHANNEL_CLASS)
 namespace grpc {
   class Channel;
 }
+#else
+namespace grpc_impl {
+  class Channel;
+}
+#endif
 
 namespace etcd
 {
@@ -383,7 +389,11 @@ namespace etcd
     pplx::task<Response> txn(etcdv3::Transaction const &txn);
 
   private:
+#if defined(WITH_GRPC_CHANNEL_CLASS)
     std::shared_ptr<grpc::Channel> channel;
+#else
+    std::shared_ptr<grpc_impl::Channel> channel;
+#endif
     std::string auth_token;
 
     struct EtcdServerStubs;