Added RdKafka hex version so that FindRdKafka.cmake can compile the test code. Changed find_dependency to find_package for the RdKafka config so that the script is not automatically exited on failure

cmake/FindRdKafka.cmake

@@ -54,7 +54,7 @@ find_package_handle_standard_args(RDKAFKA DEFAULT_MSG
 )
 
 set(CONTENTS "#include <librdkafka/rdkafka.h>\n #if RD_KAFKA_VERSION >= ${RDKAFKA_MIN_VERSION_HEX}\n int main() { }\n #endif")
-set(FILE_NAME ${CMAKE_CURRENT_BINARY_DIR}/rdkafka_version_test.c)
+set(FILE_NAME ${CMAKE_CURRENT_BINARY_DIR}/rdkafka_version_test.cpp)
 file(WRITE ${FILE_NAME} ${CONTENTS})
 
 try_compile(RdKafka_FOUND ${CMAKE_CURRENT_BINARY_DIR}

cmake/config.cmake.in

@@ -5,12 +5,14 @@ include(CMakeFindDependencyMacro)
 # Add FindRdKafka.cmake
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_CURRENT_LIST_DIR}")
 
+set(RDKAFKA_MIN_VERSION_HEX "@RDKAFKA_MIN_VERSION_HEX@")
+
 # Find boost optional
 find_dependency(Boost REQUIRED)
 
 # Try to find the RdKafka configuration file if present.
 # This will search default system locations as well as RdKafka_ROOT and RdKafka_Dir paths if specified.
-find_dependency(RdKafka QUIET CONFIG)
+find_package(RdKafka QUIET CONFIG)
 set(RDKAFKA_TARGET_IMPORTS ${RdKafka_FOUND})
 if (NOT RdKafka_FOUND)
     find_dependency(RdKafka REQUIRED MODULE)

src/CMakeLists.txt

@@ -86,7 +86,7 @@ configure_package_config_file(
     "${PROJECT_SOURCE_DIR}/cmake/config.cmake.in"
     "${CONFIG_FILE}"
     INSTALL_DESTINATION "${CPPKAFKA_CONFIG_DIR}"
-    PATH_VARS CMAKE_INSTALL_PREFIX CMAKE_INSTALL_INCLUDEDIR CMAKE_INSTALL_LIBDIR
+    PATH_VARS RDKAFKA_MIN_VERSION_HEX CMAKE_INSTALL_PREFIX CMAKE_INSTALL_INCLUDEDIR CMAKE_INSTALL_LIBDIR
 )
 
 # Generate version file