cmake: drop WITH_PYTHON2 option

* drop WITH_PYTHON2 option
* print warning message if WITH_PYTHON3 is disabled
* drop MGR_PYTHON_VERSION option, as we don't support use different
  python version for python binding and ceph-mgr embedded python
  interpreter anymore. as before switching to python3-only build,
  we can build python3 and python2 python bindings, and ceph-mgr
  can use either of them. but after switching to python3-only
  build, ceph-mgr has to use whatever python version used to
  build python binding.
* move WITH_PYTHON3 option to $top_srcdir/CMakeLists.txt, as ceph-mgr
  and python binding will share this option.
* hardware ${PYTHON_VERSION} to 3
* hardware ${Python${PYTHON_VERSION}_VERSION_MAJOR} to 3
* only build boost library with python3
* s/Python_EXECUTABLE/Python3_EXECUTABLE/
* update the build scripts and packagings accordingly
* rename all cython${PYTHON_VERSION}_* targets to cython_*
* update distutils_install_module() so it does not take python_version
  parameter anymore.

Signed-off-by: Kefu Chai <kchai@redhat.com>

CMakeLists.txt

@@ -418,23 +418,26 @@ endif (WITH_RADOSGW)
 #option for CephFS
 option(WITH_CEPHFS "CephFS is enabled" ON)
 
-#option for Mgr
+# Please specify 3.[0-7] if you want to build with a certain version of python3.
+set(WITH_PYTHON3 "3" CACHE STRING "build with specified python3 version")
+if(NOT WITH_PYTHON3)
+  message(FATAL_ERROR "WITH_PYTHON3 should always be enabled")
+elseif(WITH_PYTHON3 MATCHES "^(1|ON|YES|TRUE|Y)$")
+  set(WITH_PYTHON3 "3")
+  message(NOTICE "Please specify a Python3 version instead of a BOOLEAN")
+elseif(NOT WITH_PYTHON3 STREQUAL "3")
+  set(find_python3_exact "EXACT")
+endif()
+find_package(Python3 ${WITH_PYTHON3} ${find_python3_exact} REQUIRED
+  COMPONENTS Interpreter Development)
+unset(find_python3_exact)
+
 option(WITH_MGR "ceph-mgr is enabled" ON)
 if(WITH_MGR)
-  # Please specify 3 or 3.[0-7] if you want to build with python3 support.
-  # FindPython thinks they belong to different families.
-  set(MGR_PYTHON_VERSION "2.7" CACHE
-    STRING "required version of python runtime for running mgr plugins. ")
-  if(NOT MGR_PYTHON_VERSION MATCHES "^[23]$")
-    set(find_python_exact "EXACT")
-  endif()
-  find_package(Python ${MGR_PYTHON_VERSION} ${find_python_exact} REQUIRED
-    COMPONENTS Interpreter Development)
-  unset(find_python_exact)
-  set(MGR_PYTHON_EXECUTABLE ${Python_EXECUTABLE})
-  set(MGR_PYTHON_LIBRARIES ${Python_LIBRARIES})
-  set(MGR_PYTHON_VERSION_MAJOR ${Python_VERSION_MAJOR})
-  set(MGR_PYTHON_VERSION_MINOR ${Python_VERSION_MINOR})
+  set(MGR_PYTHON_EXECUTABLE ${Python3_EXECUTABLE})
+  set(MGR_PYTHON_LIBRARIES ${Python3_LIBRARIES})
+  set(MGR_PYTHON_VERSION_MAJOR ${Python3_VERSION_MAJOR})
+  set(MGR_PYTHON_VERSION_MINOR ${Python3_VERSION_MINOR})
   # Boost dependency check deferred to Boost section
 endif(WITH_MGR)
 

ceph.spec.in

@@ -1128,8 +1128,6 @@ ${CMAKE} .. \
     -DWITH_MANPAGE=ON \
     -DWITH_PYTHON3=%{python3_version} \
     -DWITH_MGR_DASHBOARD_FRONTEND=OFF \
-    -DWITH_PYTHON2=OFF \
-    -DMGR_PYTHON_VERSION=3 \
 %if 0%{without ceph_test_package}
     -DWITH_TESTS=OFF \
 %endif

cmake/modules/AddCephTest.cmake

@@ -38,7 +38,7 @@ if(WITH_GTEST_PARALLEL)
     add_dependencies(tests gtest-parallel_ext)
     find_package(Python REQUIRED)
     set(GTEST_PARALLEL_COMMAND
-      ${Python_EXECUTABLE} ${gtest_parallel_source_dir}/gtest-parallel)
+      ${Python3_EXECUTABLE} ${gtest_parallel_source_dir}/gtest-parallel)
   endif()
 endif()
 
@@ -62,20 +62,15 @@ function(add_tox_test name)
   else()
     set(tox_path ${CMAKE_CURRENT_SOURCE_DIR})
   endif()
-  if(WITH_PYTHON2)
-    list(APPEND tox_envs py27)
-  endif()
-  if(WITH_PYTHON3)
-    list(APPEND tox_envs py3)
-  endif()
+  list(APPEND tox_envs py3)
   if(DEFINED TOXTEST_TOX_ENVS)
     list(APPEND tox_envs ${TOXTEST_TOX_ENVS})
   endif()
   string(REPLACE ";" "," tox_envs "${tox_envs}")
   find_package(Python REQUIRED)
   add_custom_command(
     OUTPUT ${venv_path}/bin/activate
-    COMMAND ${CMAKE_SOURCE_DIR}/src/tools/setup-virtualenv.sh --python="${Python_EXECUTABLE}" ${venv_path}
+    COMMAND ${CMAKE_SOURCE_DIR}/src/tools/setup-virtualenv.sh --python="${Python3_EXECUTABLE}" ${venv_path}
     WORKING_DIRECTORY ${tox_path}
     COMMENT "preparing venv for ${name}")
   add_custom_target(${name}-venv

cmake/modules/BuildBoost.cmake

@@ -109,15 +109,15 @@ function(do_build_boost version)
     " : ${CMAKE_CXX_COMPILER}"
     " ;\n")
   if(with_python_version)
-    find_package(Python ${with_python_version} QUIET REQUIRED
+    find_package(Python3 ${with_python_version} QUIET REQUIRED
       COMPONENTS Development)
-    string(REPLACE ";" " " python_includes "${Python_INCLUDE_DIRS}")
+    string(REPLACE ";" " " python3_includes "${Python3_INCLUDE_DIRS}")
     file(APPEND ${user_config}
       "using python"
       " : ${with_python_version}"
-      " : ${Python_EXECUTABLE}"
-      " : ${python_includes}"
-      " : ${Python_LIBRARIES}"
+      " : ${Python3_EXECUTABLE}"
+      " : ${python3_includes}"
+      " : ${Python3_LIBRARIES}"
       " ;\n")
   endif()
   list(APPEND b2 --user-config=${user_config})

cmake/modules/Distutils.cmake

@@ -15,12 +15,7 @@ function(distutils_install_module name)
     add_custom_target(${name}-clone ALL
       DEPENDS ${py_clone})
   endif()
-  cmake_parse_arguments(DU "" "INSTALL_SCRIPT;PYTHON_VERSION" "" ${ARGN})
-  if(DU_PYTHON_VERSION)
-    set(python_version ${DU_PYTHON_VERSION})
-  else()
-    set(python_version 3)
-  endif()
+  cmake_parse_arguments(DU "" "INSTALL_SCRIPT" "" ${ARGN})
   install(CODE "
     set(options --prefix=${CMAKE_INSTALL_PREFIX})
     if(DEFINED ENV{DESTDIR})
@@ -35,12 +30,12 @@ function(distutils_install_module name)
       endif()
     endif()
     execute_process(
-    COMMAND ${Python${python_version}_EXECUTABLE}
+    COMMAND ${Python3_EXECUTABLE}
         setup.py install \${options}
     WORKING_DIRECTORY \"${CMAKE_CURRENT_BINARY_DIR}\")")
 endfunction(distutils_install_module)
 
-function(distutils_add_cython_module target name src python_version)
+function(distutils_add_cython_module target name src)
   get_property(compiler_launcher GLOBAL PROPERTY RULE_LAUNCH_COMPILE)
   get_property(link_launcher GLOBAL PROPERTY RULE_LAUNCH_LINK)
   # When using ccache, CMAKE_C_COMPILER is ccache executable absolute path
@@ -64,12 +59,8 @@ function(distutils_add_cython_module target name src python_version)
   set(PY_CXX ${compiler_launcher} ${CMAKE_CXX_COMPILER} ${cxx_compiler_arg1})
   set(PY_LDSHARED ${link_launcher} ${CMAKE_C_COMPILER} ${c_compiler_arg1} "-shared")
 
-  if(${Python${python_version}_VERSION_MAJOR} STREQUAL "2")
-    set(suffix_var "SO")
-  else()
-    set(suffix_var "EXT_SUFFIX")
-  endif()
-  execute_process(COMMAND "${Python${python_version}_EXECUTABLE}" -c
+  set(suffix_var "EXT_SUFFIX")
+  execute_process(COMMAND "${Python3_EXECUTABLE}" -c
     "from distutils import sysconfig; print(sysconfig.get_config_var('${suffix_var}'))"
     RESULT_VARIABLE result
     OUTPUT_VARIABLE ext_suffix
@@ -91,7 +82,7 @@ function(distutils_add_cython_module target name src python_version)
     LDFLAGS=-L${CMAKE_LIBRARY_OUTPUT_DIRECTORY}
     CYTHON_BUILD_DIR=${CMAKE_CURRENT_BINARY_DIR}
     CEPH_LIBDIR=${CMAKE_LIBRARY_OUTPUT_DIRECTORY}
-    ${Python${python_version}_EXECUTABLE} ${setup_py}
+    ${Python3_EXECUTABLE} ${setup_py}
     build --verbose --build-base ${CYTHON_MODULE_DIR}
     --build-platlib ${output_dir}
     MAIN_DEPENDENCY ${src}
@@ -101,7 +92,7 @@ function(distutils_add_cython_module target name src python_version)
     DEPENDS ${output_dir}/${name}${ext_suffix})
 endfunction(distutils_add_cython_module)
 
-function(distutils_install_cython_module name python_version)
+function(distutils_install_cython_module name)
   get_property(compiler_launcher GLOBAL PROPERTY RULE_LAUNCH_COMPILE)
   get_property(link_launcher GLOBAL PROPERTY RULE_LAUNCH_LINK)
   set(PY_CC "${compiler_launcher} ${CMAKE_C_COMPILER}")
@@ -127,7 +118,7 @@ function(distutils_install_cython_module name python_version)
     endif()
     execute_process(
        COMMAND
-           ${Python${python_version}_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/setup.py
+           ${Python3_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/setup.py
            build --verbose --build-base ${CYTHON_MODULE_DIR}
            --build-platlib ${CYTHON_MODULE_DIR}/lib.${Python${python_version}_VERSION_MAJOR}
            build_ext --cython-c-in-temp --build-temp ${CMAKE_CURRENT_BINARY_DIR} --cython-include-dirs ${PROJECT_SOURCE_DIR}/src/pybind/rados

cmake/modules/FindCython.cmake

@@ -4,7 +4,7 @@
 
 # Try to run Cython, to make sure it works:
 execute_process(
-  COMMAND ${Python${PYTHON_VERSION}_EXECUTABLE} -m cython --version
+  COMMAND ${Python3_EXECUTABLE} -m cython --version
   RESULT_VARIABLE cython_result
   ERROR_VARIABLE cython_output)
 if(cython_result EQUAL 0)

debian/rules

@@ -19,7 +19,7 @@ endif
 
 extraopts += -DWITH_OCF=ON -DWITH_LTTNG=ON
 extraopts += -DWITH_MGR_DASHBOARD_FRONTEND=OFF
-extraopts += -DWITH_PYTHON3=3 -DWITH_PYTHON2=OFF -DMGR_PYTHON_VERSION=3
+extraopts += -DWITH_PYTHON3=3
 extraopts += -DWITH_CEPHFS_JAVA=ON
 extraopts += -DWITH_CEPHFS_SHELL=ON
 extraopts += -DWITH_SYSTEMD=ON -DCEPH_SYSTEMD_ENV_DIR=/etc/default

do_cmake.sh

@@ -42,7 +42,7 @@ else
 fi
 
 if [[ "$PYBUILD" =~ ^3(\..*)?$ ]] ; then
-    ARGS+=" -DWITH_PYTHON2=OFF -DWITH_PYTHON3=${PYBUILD} -DMGR_PYTHON_VERSION=${PYBUILD}"
+    ARGS+=" -DWITH_PYTHON3=${PYBUILD}"
 fi
 
 if type ccache > /dev/null 2>&1 ; then

run-make-check.sh

@@ -54,7 +54,7 @@ function main() {
     fi
     FOR_MAKE_CHECK=1 prepare
     # Init defaults after deps are installed.
-    configure "-DWITH_GTEST_PARALLEL=ON -DWITH_FIO=ON -DWITH_SEASTAR=ON -DWITH_CEPHFS_SHELL=ON -DWITH_SPDK=ON -DENABLE_GIT_VERSION=OFF $@"
+    configure " -DWITH_PYTHON3=3 -DWITH_GTEST_PARALLEL=ON -DWITH_FIO=ON -DWITH_SEASTAR=ON -DWITH_CEPHFS_SHELL=ON -DWITH_SPDK=ON -DENABLE_GIT_VERSION=OFF $@"
     build tests && echo "make check: successful run on $(git rev-parse HEAD)"
     run
 }

src/CMakeLists.txt

@@ -218,42 +218,9 @@ if(WITH_CEPHFS_JAVA)
 endif()
 
 # Python stuff
-option(WITH_PYTHON2 "build python2 bindings" ON)
+option(WITH_PYTHON2 "build python2 bindings" OFF)
 if(WITH_PYTHON2)
-  find_package(Python2 REQUIRED
-    COMPONENTS Interpreter Development)
-endif()
-
-set(WITH_PYTHON3 "OFF" CACHE STRING "build python3 bindings with specified python3 version")
-if(WITH_PYTHON3)
-  if(WITH_PYTHON3 MATCHES "^(1|ON|YES|TRUE|Y)$")
-    set(WITH_PYTHON3 "3")
-  endif()
-  if(NOT WITH_PYTHON3 STREQUAL "3")
-    set(find_python3_exact "EXACT")
-  endif()
-  find_package(Python3 ${WITH_PYTHON3} ${find_python3_exact} REQUIRED
-    COMPONENTS Interpreter Development)
-  unset(find_python3_exact)
-endif()
-
-# the major version of the python bindings as a dependency of other
-# targets
-if(WITH_PYTHON2)
-  set(PY_BINDING_INFIX 2)
-else()
-  set(PY_BINDING_INFIX 3)
-endif()
-# use python2 by default for python bindings, tools and tests, before
-# switching to python3
-# Python_EXECUTABLE` can be set by `find_package(Python ...)` also. and we do
-# call `find_package(Python ...)` in `ceph/CMakeLists.txt`. but we do so before
-# `add_subdirectory(src)` where `Python_EXECUTABLE` is set. so it's safe to
-# use this variable name and call `find_package(Python ...)`.
-if(WITH_PYTHON2)
-  set(Python_EXECUTABLE ${Python2_EXECUTABLE})
-else()
-  set(Python_EXECUTABLE ${Python3_EXECUTABLE})
+  message(FATAL_ERROR "Python 2 is not supported anymore")
 endif()
 
 # sort out which allocator to use
@@ -787,17 +754,17 @@ add_custom_target(vstart-base DEPENDS
     monmaptool
     crushtool
     rados
-    cython${PY_BINDING_INFIX}_rados)
+    cython_rados)
 if (WITH_MGR)
   add_dependencies(vstart-base ceph-mgr)
 endif()
 
 add_custom_target(vstart DEPENDS vstart-base)
-if (WITH_RBD)
-  add_dependencies(vstart cython${PY_BINDING_INFIX}_rbd)
+if(WITH_RBD)
+  add_dependencies(vstart cython_rbd)
 endif()
 if (WITH_CEPHFS)
-  add_dependencies(vstart ceph-mds cephfs cython${PY_BINDING_INFIX}_cephfs)
+  add_dependencies(vstart ceph-mds cephfs cython_cephfs)
 endif()
 if(WITH_RADOSGW)
   add_dependencies(vstart radosgw radosgw-admin)
@@ -819,7 +786,7 @@ endif()
 add_custom_target(cephfs_testing DEPENDS
     vstart
     rados
-    cython${PY_BINDING_INFIX}_modules
+    cython_modules
     cephfs
     cls_cephfs
     ceph-fuse

src/ceph-crash.in

@@ -1,4 +1,4 @@
-#!@Python_EXECUTABLE@
+#!@Python3_EXECUTABLE@
 # -*- mode:python -*-
 # vim: ts=4 sw=4 smarttab expandtab
 

src/ceph-volume/CMakeLists.txt

@@ -1,15 +1,8 @@
 
 include(Distutils)
 
-if(WITH_PYTHON2)
-  set(python_version_major 2)
-else()
-  set(python_version_major 3)
-endif()
-
 distutils_install_module(ceph_volume
-  INSTALL_SCRIPT ${CMAKE_INSTALL_FULL_SBINDIR}
-  PYTHON_VERSION ${python_version_major})
+  INSTALL_SCRIPT ${CMAKE_INSTALL_FULL_SBINDIR})
 
 if(FREEBSD)
   add_subdirectory(plugin/zfs)

src/ceph-volume/plugin/zfs/CMakeLists.txt

@@ -1,4 +1,3 @@
 
 distutils_install_module(ceph_volume_zfs
-  INSTALL_SCRIPT ${CMAKE_INSTALL_FULL_SBINDIR}
-  PYTHON_VERSION ${python_version})
+  INSTALL_SCRIPT ${CMAKE_INSTALL_FULL_SBINDIR})

src/ceph.in

@@ -1,4 +1,4 @@
-#!@Python_EXECUTABLE@
+#!@Python3_EXECUTABLE@
 # -*- mode:python -*-
 # vim: ts=4 sw=4 smarttab expandtab
 #
@@ -66,7 +66,7 @@ DEVMODEMSG = '*** DEVELOPER MODE: setting PATH, PYTHONPATH and LD_LIBRARY_PATH *
 def respawn_in_path(lib_path, pybind_path, pythonlib_path, asan_lib_path):
     execv_cmd = []
     if 'CEPH_DBG' in os.environ:
-        execv_cmd += ['@Python_EXECUTABLE@', '-mpdb']
+        execv_cmd += ['@Python3_EXECUTABLE@', '-mpdb']
 
     if platform.system() == "Darwin":
         lib_path_var = "DYLD_LIBRARY_PATH"

src/mgr/CMakeLists.txt

@@ -30,12 +30,11 @@ if(WITH_MGR)
     mgr_commands.cc
     $<TARGET_OBJECTS:mgr_cap_obj>)
   add_executable(ceph-mgr ${mgr_srcs})
-  target_include_directories(ceph-mgr SYSTEM PRIVATE "${Python_INCLUDE_DIRS}")
   target_link_libraries(ceph-mgr
     osdc client heap_profiler
     global-static ceph-common
     Boost::python${MGR_PYTHON_VERSION_MAJOR}${MGR_PYTHON_VERSION_MINOR}
-    ${MGR_PYTHON_LIBRARIES} ${CMAKE_DL_LIBS} ${GSSAPI_LIBRARIES})
+    Python3::Python ${CMAKE_DL_LIBS} ${GSSAPI_LIBRARIES})
   set_target_properties(ceph-mgr PROPERTIES
     POSITION_INDEPENDENT_CODE ${EXE_LINKER_USE_PIE})
   install(TARGETS ceph-mgr DESTINATION bin)