possibility to override the PYTHON_SITE_PACKAGES_INSTALL_DIR

Author: dom

docs/developer/developer.adoc

@@ -97,6 +97,22 @@ $ cd build/
 $ cmake ../
 $ make
 ----
+
+On Ubuntu 18.04 and potentially other distro, the python3 install path is wrong.
+If the following command:
+
+----
+$ python3 -c "from distutils.sysconfig import get_python_lib; print(get_python_lib(True))"
+----
+
+return "/usr/local/lib/python3/dist-packages" instead of a path like
+"/usr/local/lib/python3.6/dist-packages", you must override this path,
+otherwise you will not be able to import openscap_api.
+
+----
+$ cmake ../ -DPYTHON_SITE_PACKAGES_INSTALL_DIR=/usr/local/lib/python3.6/dist-packages
+----
+
 --
 
 . *Build the HTML documentation*

swig/python3/CMakeLists.txt

@@ -24,11 +24,14 @@ add_custom_command(OUTPUT ${PYTHON_COMPILED_FILES}
 )
 add_custom_target(python3_compile ALL DEPENDS ${PYTHON_COMPILED_FILES})
 
+if(NOT PYTHON_SITE_PACKAGES_INSTALL_DIR)
 execute_process(COMMAND
 	${PYTHON_EXECUTABLE} -c "from distutils.sysconfig import get_python_lib; print(get_python_lib(True, prefix='${CMAKE_INSTALL_PREFIX}'))"
 	OUTPUT_VARIABLE PYTHON_SITE_PACKAGES_INSTALL_DIR
 	OUTPUT_STRIP_TRAILING_WHITESPACE
 )
+endif()
+
 install(TARGETS ${SWIG_MODULE_openscap_py_REAL_NAME}
 	DESTINATION ${PYTHON_SITE_PACKAGES_INSTALL_DIR}
 )

utils/CMakeLists.txt

@@ -45,11 +45,15 @@ if(ENABLE_OSCAP_UTIL_DOCKER)
 		DESTINATION ${CMAKE_CURRENT_BINARY_DIR}
 		FILE_PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE GROUP_READ GROUP_EXECUTE WORLD_READ WORLD_EXECUTE
 	)
+	
+	if(NOT PYTHON_SITE_PACKAGES_INSTALL_DIR)
 	execute_process(COMMAND
 		${OSCAP_DOCKER_PYTHON} -c "from distutils.sysconfig import get_python_lib; print(get_python_lib(False, False, prefix='${CMAKE_INSTALL_PREFIX}'))"
 		OUTPUT_VARIABLE PYTHON_SITE_PACKAGES_INSTALL_DIR
 		OUTPUT_STRIP_TRAILING_WHITESPACE
 	)
+	endif()
+	
 	install(DIRECTORY oscap_docker_python
 		DESTINATION ${PYTHON_SITE_PACKAGES_INSTALL_DIR}
 	)