Reliable macro condition to adapt to different version of gRPC. (#187)

CMakeLists.txt

@@ -122,6 +122,7 @@ else()
     include(${CMAKE_CURRENT_SOURCE_DIR}/cmake/FindGRPC.cmake)
     set(GRPC_LIBRARIES ${GPR_LIBRARY} ${GRPC_LIBRARY} ${GRPC_GRPC++_LIBRARY})
 endif()
+message("-- Found GRPC: ${GRPC_LIBRARIES} (found version: \"${gRPC_VERSION}\")")
 # avoid use the apt-get installed libgrpc-dev (version v1.13) on Ubuntu 18.04
 if(gRPC_FOUND AND gRPC_VERSION VERSION_LESS "1.14")
     message(FATAL_ERROR "gRPC '${gRPC_VERSION}' is not supported, please install a newer gRPC library "
@@ -131,6 +132,10 @@ if(gRPC_FOUND AND gRPC_VERSION VERSION_LESS "1.14")
 endif()
 include(${CMAKE_CURRENT_SOURCE_DIR}/cmake/GenerateProtobufGRPC.cmake)
 
+if(gRPC_VERSION VERSION_LESS "1.21" OR gRPC_VERSION VERSION_GREATER "1.31")
+    add_definitions(-DWITH_GRPC_CHANNEL_CLASS)
+endif()
+
 # will set `PROTOBUF_GENERATES`, indicates all generated .cc files, and a target `protobuf_generates`.
 include(${CMAKE_CURRENT_SOURCE_DIR}/cmake/GenerateProtobuf.cmake)
 add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/proto)
@@ -153,19 +158,6 @@ if(W_NO_CPP17_EXTENSIONS)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-c++17-extensions")
 endif()
 
-set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -std=c++11")
-set(CMAKE_REQUIRED_INCLUDES "${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)
 
 add_subdirectory(src)

src/Client.cpp

@@ -82,13 +82,7 @@ etcd::Client::Client(std::string const & address,
 }
 
 etcd::Client::Client(std::string const & address,
-#if defined(WITH_GRPC_CHANNEL_CLASS)
+                     grpc::ChannelArguments const & arguments)
-           grpc::ChannelArguments const & arguments
-#else
-           grpc_impl::ChannelArguments const & arguments
-#endif
-
-                     )
 {
   this->own_client = true;
   this->client = new SyncClient(address, arguments);
@@ -100,13 +94,7 @@ etcd::Client *etcd::Client::WithUrl(std::string const & etcd_url,
 }
 
 etcd::Client *etcd::Client::WithUrl(std::string const & etcd_url,
-#if defined(WITH_GRPC_CHANNEL_CLASS)
+                                    grpc::ChannelArguments const & arguments) {
-           grpc::ChannelArguments const & arguments
-#else
-           grpc_impl::ChannelArguments const & arguments
-#endif
-
-                                    ) {
   return new etcd::Client(etcd_url, arguments);
 }
 
@@ -124,13 +112,7 @@ etcd::Client::Client(std::string const & address,
                      std::string const & username,
                      std::string const & password,
                      int const auth_token_ttl,
-#if defined(WITH_GRPC_CHANNEL_CLASS)
+                     grpc::ChannelArguments const & arguments)
-           grpc::ChannelArguments const & arguments
-#else
-           grpc_impl::ChannelArguments const & arguments
-#endif
-
-                     )
 {
   this->own_client = true;
   this->client = new SyncClient(address, username, password, auth_token_ttl, arguments);
@@ -148,13 +130,7 @@ etcd::Client *etcd::Client::WithUser(std::string const & etcd_url,
                                      std::string const & username,
                                      std::string const & password,
                                      int const auth_token_ttl,
-#if defined(WITH_GRPC_CHANNEL_CLASS)
+                                     grpc::ChannelArguments const & arguments) {
-           grpc::ChannelArguments const & arguments
-#else
-           grpc_impl::ChannelArguments const & arguments
-#endif
-
-                                     ) {
   return new etcd::Client(etcd_url, username, password, auth_token_ttl, arguments);
 }
 
@@ -175,13 +151,7 @@ etcd::Client::Client(std::string const & address,
                      std::string const & cert,
                      std::string const & privkey,
                      std::string const & target_name_override,
-#if defined(WITH_GRPC_CHANNEL_CLASS)
+                     grpc::ChannelArguments const & arguments)
-           grpc::ChannelArguments const & arguments
-#else
-           grpc_impl::ChannelArguments const & arguments
-#endif
-
-                     )
 {
   this->own_client = true;
   this->client = new SyncClient(address, ca, cert, privkey, target_name_override, arguments);
@@ -197,11 +167,7 @@ etcd::Client *etcd::Client::WithSSL(std::string const & etcd_url,
 }
 
 etcd::Client *etcd::Client::WithSSL(std::string const & etcd_url,
-#if defined(WITH_GRPC_CHANNEL_CLASS)
                                     grpc::ChannelArguments const & arguments,
-#else
-                                 grpc_impl::ChannelArguments const & arguments,
-#endif
                                     std::string const & ca,
                                     std::string const & cert,
                                     std::string const & privkey,

src/SyncClient.cpp

@@ -271,12 +271,7 @@ etcd::SyncClient::SyncClient(std::string const & address,
 }
 
 etcd::SyncClient::SyncClient(std::string const & address,
-                     #if defined(WITH_GRPC_CHANNEL_CLASS)
+                             grpc::ChannelArguments const & arguments)
-           grpc::ChannelArguments const & arguments
-#else
-           grpc_impl::ChannelArguments const & arguments
-#endif
-                     )
 {
   // create channels
   std::string const addresses = etcd::detail::strip_and_resolve_addresses(address);
@@ -302,12 +297,7 @@ etcd::SyncClient *etcd::SyncClient::WithUrl(std::string const & etcd_url,
 }
 
 etcd::SyncClient *etcd::SyncClient::WithUrl(std::string const & etcd_url,
-                                    #if defined(WITH_GRPC_CHANNEL_CLASS)
+                                            grpc::ChannelArguments const & arguments) {
-                                 grpc::ChannelArguments const & arguments
-#else
-                                 grpc_impl::ChannelArguments const & arguments
-#endif
-                                    ) {
   return new etcd::SyncClient(etcd_url, arguments);
 }
 
@@ -342,13 +332,7 @@ etcd::SyncClient::SyncClient(std::string const & address,
                      std::string const & username,
                      std::string const & password,
                      int const auth_token_ttl,
-                     #if defined(WITH_GRPC_CHANNEL_CLASS)
+                     grpc::ChannelArguments const & arguments)
-           grpc::ChannelArguments const & arguments
-#else
-           grpc_impl::ChannelArguments const & arguments
-#endif
-
-                     )
 {
   // create channels
   std::string const addresses = etcd::detail::strip_and_resolve_addresses(address);
@@ -382,12 +366,7 @@ etcd::SyncClient *etcd::SyncClient::WithUser(std::string const & etcd_url,
                                      std::string const & username,
                                      std::string const & password,
                                      int const auth_token_ttl,
-                                     #if defined(WITH_GRPC_CHANNEL_CLASS)
+                                     grpc::ChannelArguments const & arguments) {
-                                  grpc::ChannelArguments const & arguments
-#else
-                                  grpc_impl::ChannelArguments const & arguments
-#endif
-                                     ) {
   return new etcd::SyncClient(etcd_url, username, password, auth_token_ttl, arguments);
 }
 
@@ -427,13 +406,7 @@ etcd::SyncClient::SyncClient(std::string const & address,
                      std::string const & cert,
                      std::string const & privkey,
                      std::string const & target_name_override,
-                     #if defined(WITH_GRPC_CHANNEL_CLASS)
+                     grpc::ChannelArguments const & arguments)
-           grpc::ChannelArguments const & arguments
-#else
-           grpc_impl::ChannelArguments const & arguments
-#endif
-
-                     )
 {
   // create channels
   std::string const addresses = etcd::detail::strip_and_resolve_addresses(address);
@@ -467,11 +440,7 @@ etcd::SyncClient *etcd::SyncClient::WithSSL(std::string const & etcd_url,
 }
 
 etcd::SyncClient *etcd::SyncClient::WithSSL(std::string const & etcd_url,
-                                    #if defined(WITH_GRPC_CHANNEL_CLASS)
                                             grpc::ChannelArguments const & arguments,
-#else
-                                 grpc_impl::ChannelArguments const & arguments,
-#endif
                                             std::string const & ca,
                                             std::string const & cert,
                                             std::string const & privkey,