makefile.python: hardening - drop virtualenv, drop build support py2

From py3.3 on a subset of virtualenv is built-in, so you can run '-m venv' ot of
the box.

- replace: $(PY_ENV_BIN)/pip --> $(PY_ENV_BIN)/python -m pip
- remove obsolete virtualenv-exe target and adjust VTENV_OPTS
- remove obsolete msg-pip-exe target
- print list of py launchers available from $(PY_ENV_BIN) to the log
- fix hard coded ./local

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

.travis.yml

@@ -28,7 +28,6 @@ stages:
 
 jobs:
   include:
-    - python: "2.7"
     - python: "3.5"
     - python: "3.6"
     - stage: docker

utils/makefile.python

@@ -5,6 +5,7 @@ PYOBJECTS ?=
 
 SITE_PYTHON ?=$(dir $(abspath $(lastword $(MAKEFILE_LIST))))site-python
 export PYTHONPATH := $(SITE_PYTHON):$$PYTHONPATH
+export PY_ENV PYDIST PYBUILD
 
 # folder where the python distribution takes place
 PYDIST   ?= ./py_dist
@@ -12,6 +13,9 @@ PYDIST   ?= ./py_dist
 PYBUILD  ?= ./py_build
 # python version to use
 PY       ?=3
+# $(PYTHON) points to the python interpreter from the OS!  The python from the
+# OS is needed e.g. to create a virtualenv.  For tasks inside the virtualenv the
+# interpeter from '$(PY_ENV_BIN)/python' is used.
 PYTHON   ?= python$(PY)
 PIP      ?= pip$(PY)
 PIP_INST ?= --user
@@ -26,7 +30,7 @@ PYLINT_RC ?= .pylintrc
 TEST_FOLDER  ?= ./tests
 TEST         ?= .
 
-VTENV_OPTS   = "--no-site-packages"
+VTENV_OPTS   ?=
 PY_ENV       = ./local/py$(PY)
 PY_ENV_BIN   = $(PY_ENV)/bin
 PY_ENV_ACT   = . $(PY_ENV_BIN)/activate
@@ -37,20 +41,6 @@ ifeq ($(OS),Windows_NT)
   PY_ENV_ACT = $(PY_ENV_BIN)/activate
 endif
 
-ifeq ($(PYTHON),python)
-  VIRTUALENV   = virtualenv
-else
-  VIRTUALENV   = virtualenv --python=$(PYTHON)
-endif
-
-ifeq ($(KBUILD_VERBOSE),1)
-  PIP_VERBOSE =
-  VIRTUALENV_VERBOSE =
-else
-  PIP_VERBOSE = "-q"
-  VIRTUALENV_VERBOSE = "-q"
-endif
-
 python-help::
 	@echo  'makefile.python:'
 	@echo  '  pyenv | pyenv[un]install'
@@ -59,7 +49,7 @@ python-help::
 	@echo  '    pylint    - run pylint *linting*'
 	@echo  '    pytest    - run *tox* test on python objects'
 	@echo  '    pydebug   - run tests within a PDB debug session'
-	@echo  '    pybuild   - build python packages'
+	@echo  '    pybuild   - build python packages ($(PYDIST) $(PYBUILD))'
 	@echo  '    pyclean   - clean intermediate python objects'
 	@echo  '  targets using system users environment:'
 	@echo  '    py[un]install - [un]install python objects in editable mode'
@@ -94,38 +84,6 @@ python-exe:
 	@:
 endif
 
-msg-pip-exe:
-	@echo "\n  $(PIP) is required\n\n\
-  Make sure you have updated pip installed, grab it from\n\
-  https://pip.pypa.io or install it from your package\n\
-  manager. On debian based OS these requirements are\n\
-  installed by::\n\n\
-    sudo -H apt-get install python$(PY)-pip\n" | $(FMT)
-
-ifeq ($(shell which $(PIP) >/dev/null 2>&1; echo $$?), 1)
-pip-exe: msg-pip-exe
-	$(error The '$(PIP)' command was not found)
-else
-pip-exe:
-	@:
-endif
-
-PHONY += msg-virtualenv-exe virtualenv-exe
-msg-virtualenv-exe:
-	@echo "\n  virtualenv is required\n\n\
-  Make sure you have an updated virtualenv installed, grab it from\n\
-  https://virtualenv.pypa.io/en/stable/installation/ or install it\n\
-  via pip by::\n\n\
-    pip install --user https://github.com/pypa/virtualenv/tarball/master\n" | $(FMT)
-
-ifeq ($(shell which virtualenv >/dev/null 2>&1; echo $$?), 1)
-virtualenv-exe: msg-virtualenv-exe
-	$(error The 'virtualenv' command was not found)
-else
-virtualenv-exe:
-	@:
-endif
-
 # ------------------------------------------------------------------------------
 # commands
 # ------------------------------------------------------------------------------
@@ -136,9 +94,9 @@ quiet_cmd_pyinstall = INSTALL   $2
 
 # $2 path to folder with setup.py, this uses pip from pyenv (not OS!)
 quiet_cmd_pyenvinstall = PYENV     install $2
-      cmd_pyenvinstall = $(PY_ENV_BIN)/pip $(PIP_VERBOSE) install -e $2$(PY_SETUP_EXTRAS)
+      cmd_pyenvinstall = $(PY_ENV_BIN)/python -m pip $(PIP_VERBOSE) install -e $2$(PY_SETUP_EXTRAS)
 
-# Uninstall the package. Since pip does not uninstall the no longer needed
+# Uninstall the package.  Since pip does not uninstall the no longer needed
 # depencies (something like autoremove) the depencies remain.
 
 # $2 package name to uninstall, this uses pip from the OS.
@@ -147,16 +105,19 @@ quiet_cmd_pyuninstall = UNINSTALL $2
 
 # $2 path to folder with setup.py, this uses pip from pyenv (not OS!)
 quiet_cmd_pyenvuninstall = PYENV     uninstall   $2
-      cmd_pyenvuninstall = $(PY_ENV_BIN)/pip $(PIP_VERBOSE) uninstall --yes $2
+      cmd_pyenvuninstall = $(PY_ENV_BIN)/python -m pip $(PIP_VERBOSE) uninstall --yes $2
 
 # $2 path to folder where virtualenv take place
+# creating a virtualenv uses $(PYTHON) from the OS!
 quiet_cmd_virtualenv  = PYENV     usage: $ source ./$@/bin/activate
       cmd_virtualenv  = \
-	if [ ! -d "./$(PY_ENV)" ];then                                  \
-		$(VIRTUALENV) $(VIRTUALENV_VERBOSE) $(VTENV_OPTS) $2;   \
+	if [ ! -d "$(PY_ENV)" ];then                                    \
+		echo "PYENV     create virtualenv $2";                  \
+		$(PYTHON) -m venv $(VTENV_OPTS) $2;                     \
 	else                                                            \
 		echo "PYENV     using virtualenv from $2";              \
-        fi
+        fi; \
+	echo "commands available at $(PY_ENV_BIN):"; ls $(PY_ENV_BIN) | $(FMT) ;
 
 # $2 path to lint
 quiet_cmd_pylint      = LINT      $@
@@ -192,14 +153,14 @@ quiet_cmd_pytest      = TEST      $@
 # .. _installing: https://packaging.python.org/tutorials/installing-packages/
 #
 quiet_cmd_pybuild     = BUILD     $@
-      cmd_pybuild     = $(PY_ENV_BIN)/$(PYTHON) setup.py \
+      cmd_pybuild     = $(PY_ENV_BIN)/python setup.py \
 			sdist -d $(PYDIST)  \
 			bdist_wheel --bdist-dir $(PYBUILD) -d $(PYDIST)
 
 quiet_cmd_pyclean     = CLEAN     $@
 # remove 'build' folder since bdist_wheel does not care the --bdist-dir
       cmd_pyclean     = \
-	rm -rf $(PYDIST) $(PYBUILD) ./local ./.tox *.egg-info     ;\
+	rm -rf $(PYDIST) $(PYBUILD) $(PY_ENV) ./.tox *.egg-info     ;\
 	find . -name '*.pyc' -exec rm -f {} +      ;\
 	find . -name '*.pyo' -exec rm -f {} +      ;\
 	find . -name __pycache__ -exec rm -rf {} +
@@ -230,15 +191,16 @@ PHONY += pyclean
 pyclean:
 	$(call cmd,pyclean)
 
-# to build *local* environment, python and virtualenv from the OS is needed!
+# to build *local* environment, python from the OS is needed!
 pyenv: $(PY_ENV)
-$(PY_ENV): virtualenv-exe python-exe
+$(PY_ENV): python-exe
 	$(call cmd,virtualenv,$(PY_ENV))
-	@$(PY_ENV_BIN)/pip install $(PIP_VERBOSE) -r requirements.txt
+	$(Q)$(PY_ENV_BIN)/python -m pip install $(PIP_VERBOSE) -U pip wheel pip setuptools
+	$(Q)$(PY_ENV_BIN)/python -m pip install $(PIP_VERBOSE) -r requirements.txt
 
 PHONY += pylint-exe
 pylint-exe: $(PY_ENV)
-	@$(PY_ENV_BIN)/pip $(PIP_VERBOSE) install pylint
+	@$(PY_ENV_BIN)/python -m pip $(PIP_VERBOSE) install pylint
 
 PHONY += pylint
 pylint: pylint-exe
@@ -262,15 +224,15 @@ pydebug: $(PY_ENV)
 
 # install / uninstall python objects into virtualenv (PYENV)
 pyenv-install: $(PY_ENV)
-	@$(PY_ENV_BIN)/pip $(PIP_VERBOSE) install -e .
+	@$(PY_ENV_BIN)/python -m pip $(PIP_VERBOSE) install -e .
 	@echo "ACTIVATE  $(call normpath,$(PY_ENV_ACT)) "
 
 pyenv-uninstall: $(PY_ENV)
-	@$(PY_ENV_BIN)/pip $(PIP_VERBOSE) uninstall --yes .
+	@$(PY_ENV_BIN)/python -m pip $(PIP_VERBOSE) uninstall --yes .
 
 # runs python interpreter from ./local/py<N>/bin/python
 pyenv-python: pyenv-install
-	cd ./local; ../$(PY_ENV_BIN)/python -i
+	$(PY_ENV_BIN)/python -i
 
 # With 'dependency_links=' setuptools supports dependencies on packages hosted
 # on other reposetories then PyPi, see "Packages Not On PyPI" [1].  The big
@@ -284,7 +246,7 @@ pyenv-python: pyenv-install
 
 # https://github.com/pypa/twine
 PHONY += upload-pypi
-upload-pypi: pyclean pybuild
+upload-pypi: pyclean pyenvinstall pybuild
 	@$(PY_ENV_BIN)/twine upload $(PYDIST)/*
 
 .PHONY: $(PHONY)