Fix the python 3 support and drop python 2 and 3.5

OpenStack is dropping the py2.7 and py3.5 support in ussuri cycle.

python-tempestconf is python 3 ready and ok to drop the python 2.7
and python 3.5 support. Last python-tempestconf version officially supporting
python 2.7 and python 3.5 is 2.5.0

From now on, python-tempestconf will test all stable branches with py3
jobs.
Complete discussion & schedule can be found in
- http://lists.openstack.org/pipermail/openstack-discuss/2019-October/010142.html
- https://etherpad.openstack.org/p/drop-python2-support

Ussuri Communtiy-wide goal:
https://governance.openstack.org/tc/goals/selected/ussuri/drop-py27.html

The patch disables swift service for queens job only due to swift issues
on py3 in queens.

Story: 2007107
Task: 38163
Task: 38164

Change-Id: I0d38195f0cfbdf52a0a7e7ec721cfa9a3e2c6ea8

.zuul.yaml

@@ -1,8 +1,6 @@
 - project:
     templates:
       - openstack-cover-jobs
-      - openstack-python-jobs
-      - openstack-python35-jobs
       - openstack-python36-jobs
       - openstack-python37-jobs
       - publish-openstack-docs-pti
@@ -14,9 +12,7 @@
         - python-tempestconf-tempest-devstack-admin-stein
         - python-tempestconf-tempest-devstack-admin-rocky
         - python-tempestconf-tempest-devstack-admin-queens
-        - python-tempestconf-tempest-devstack-admin-py3
         - python-tempestconf-tempest-devstack-demo
-        - python-tempestconf-tempest-devstack-demo-py3
         - python-tempestconf-tempest-packstack-admin:
             voting: false
         - python-tempestconf-tempest-packstack-demo:
@@ -32,9 +28,7 @@
         - python-tempestconf-tempest-devstack-admin-stein
         - python-tempestconf-tempest-devstack-admin-rocky
         - python-tempestconf-tempest-devstack-admin-queens
-        - python-tempestconf-tempest-devstack-admin-py3
         - python-tempestconf-tempest-devstack-demo
-        - python-tempestconf-tempest-devstack-demo-py3
         - python-tempestconf-tempest-packstack-admin:
             voting: false
         - python-tempestconf-tempest-packstack-demo:
@@ -75,15 +69,17 @@
         '{{ devstack_base_dir }}/tempest/tempest.log': logs
         '{{ devstack_base_dir }}/tempest/etc/tempest.conf': logs
         '{{ zuul.project.src_dir }}/etc/accounts.yaml': logs
+      tempestconf_pip_virtualenv_python: "python3"
       devstack_plugins:
         heat: https://opendev.org/openstack/heat
         manila: https://opendev.org/openstack/manila
         manila-ui: https://opendev.org/openstack/manila-ui
         designate: https://opendev.org/openstack/designate
       devstack_localrc:
+        USE_PYTHON3: True
         MANILA_USE_UWSGI: False
         MANILA_USE_MOD_WSGI: False
-      devstack_services:
+      devstack_services: &devstack_services
         h-eng: True
         h-api: True
         h-api-cfn: True
@@ -191,6 +187,13 @@
     override-checkout: stable/queens
     vars:
       branch: stable/queens
+      devstack_services:
+        <<: *devstack_services
+        # disable Swift services
+        s-account: false
+        s-container: false
+        s-object: false
+        s-proxy: false
 
 - job:
     name: python-tempestconf-tempest-devstack-demo
@@ -238,6 +241,13 @@
     override-checkout: stable/queens
     vars:
       branch: stable/queens
+      devstack_services:
+        <<: *devstack_services
+        # disable Swift services
+        s-account: false
+        s-container: false
+        s-object: false
+        s-proxy: false
 
 - job:
     name: python-tempestconf-tempest-packstack-admin
@@ -258,39 +268,3 @@
       user: demo
       test_demo: true
       cloud_admin: packstack-admin
-
-- job:
-    name: python-tempestconf-tempest-devstack-admin-py3
-    parent: python-tempestconf-tempest-devstack-admin
-    description: |
-      Tempest job for python-tempestconf on a devstack environment with python3 enabled.
-    vars:
-      tempestconf_pip_virtualenv_python: "python3"
-      devstack_localrc:
-        USE_PYTHON3: true
-      devstack_services:
-        s-account: false
-        s-container: false
-        s-object: false
-        s-proxy: false
-        # without Swift, c-bak cannot run (in the Gate at least)
-        c-bak: false
-
-- job:
-    name: python-tempestconf-tempest-devstack-demo-py3
-    parent: python-tempestconf-tempest-devstack-demo
-    description: |
-      Tempest job for python-tempestconf on a devstack environment with python3 enabled
-      for demo users.
-    vars:
-      aditional_tempestconf_params: "auth.tempest_roles member"
-      tempestconf_pip_virtualenv_python: "python3"
-      devstack_localrc:
-        USE_PYTHON3: true
-      devstack_services:
-        s-account: false
-        s-container: false
-        s-object: false
-        s-proxy: false
-        # without Swift, c-bak cannot run (in the Gate at least)
-        c-bak: false

doc/source/contributor/contributing.rst

@@ -66,7 +66,7 @@ If you've made any changes in the documentation (under ``doc/``) run::
 
 If you've made any changes in the source code run unit tests as follows::
 
-    $ tox -epy27
+    $ tox -epy36
 
 and **pep8** check like following::
 

doc/source/install/installation.rst

@@ -21,16 +21,10 @@ Git
 
 4. *(optional)* Instead of manual installation described in steps 2 and 3
    above, tox can be used for installing the requirements as well.
-   To create python 2.7 environment run following::
+   To create python 3.6 environment run following::
-
-    $ tox -epy27
-    $ source .tox/py27/bin/activate
-
-   and python 3.5 environment can be created as follows::
-
-    $ tox -epy35
-    $ source .tox/py35/bin/activate
 
+    $ tox -epy36
+    $ source .tox/py36/bin/activate
 
 RPM Installation (RDO)
 ----------------------

releasenotes/notes/drop-py2-7-5f618ce22079b071.yaml

@@ -0,0 +1,7 @@
+---
+upgrade:
+  - |
+    Python 2.7 and python 3.5 support have been dropped. Last release
+    of python-tempestconf to support python 2.7 and python 3.5 is
+    python-tempestconf 2.5.0. The minimum version of Python now supported
+    by python-tempestconf is Python 3.6.

setup.cfg

@@ -13,10 +13,7 @@ classifier =
     License :: OSI Approved :: Apache Software License
     Operating System :: POSIX :: Linux
     Programming Language :: Python
-    Programming Language :: Python :: 2
-    Programming Language :: Python :: 2.7
     Programming Language :: Python :: 3
-    Programming Language :: Python :: 3.5
     Programming Language :: Python :: 3.6
 
 [files]

tox.ini

@@ -1,9 +1,13 @@
 [tox]
-minversion = 2.0
+minversion = 3.1.1
-envlist = py37,py36,py35,py27,pypy,pep8
+envlist = py37,py36,pypy,pep8
 skipsdist = True
+# this allows tox to infer the base python from the environment name
+# and override any basepython configured in this file
+ignore_basepython_conflict = true
 
 [testenv]
+basepython = python3
 usedevelop = True
 install_command = pip install -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master} {opts} {packages}
 setenv =
@@ -18,15 +22,12 @@ commands =
     stestr --test-path ./config_tempest/tests run {posargs}
 
 [testenv:pep8]
-basepython = python3
 commands = flake8 {posargs}
 
 [testenv:venv]
-basepython = python3
 commands = {posargs}
 
 [testenv:cover]
-basepython = python3
 setenv =
   {[testenv]setenv}
   PYTHON=coverage run --source config_tempest --parallel-mode
@@ -40,18 +41,15 @@ commands =
     coverage report
 
 [testenv:docs]
-basepython = python3
 deps = -r{toxinidir}/doc/requirements.txt
 commands = sphinx-build -b html doc/source doc/build/html
 
 [testenv:releasenotes]
-basepython = python3
 deps = -r{toxinidir}/doc/requirements.txt
 commands =
   sphinx-build -a -E -W -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html
 
 [testenv:debug]
-basepython = python3
 commands = oslo_debug_helper {posargs}
 
 [flake8]