[ussuri][goal] Drop python 2.7 support and testing

OpenStack is dropping the py2.7 support in ussuri cycle.

ironic-tempest-plugin is ready with python 3 and ok to drop the
python 2.7 support.

All stable jobs need to run on py3 as master ironic-tempest-plugin
cannot support py2 anymore. Any py2 cloud/env can be tested by
installing the Temepest and plugins on py3 venv.

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

Change-Id: Ibea78605aedb955e3dc70252ca380c7e5f8f8726

releasenotes/notes/drop-py-2-7-c81e7ff14950791b.yaml

@@ -0,0 +1,6 @@
+---
+upgrade:
+  - |
+    Python 2.7 support has been dropped. Last release of ironic-tempest-plugin
+    to support py2.7 is OpenStack Train. The minimum version of Python now
+    supported by ironic-tempest-plugin is Python 3.6.

setup.cfg

@@ -13,10 +13,9 @@ 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
+    Programming Language :: Python :: 3.7
 
 [files]
 packages =

test-requirements.txt

@@ -4,8 +4,7 @@
 
 hacking!=0.13.0,<0.14,>=0.12.0 # Apache-2.0
 
-sphinx!=1.6.6,!=1.6.7,>=1.6.2,<2.0.0;python_version=='2.7' # BSD
-sphinx!=1.6.6,!=1.6.7,>=1.6.2;python_version>='3.4' # BSD
+sphinx!=1.6.6,!=1.6.7,>=1.6.2 # BSD
 openstackdocstheme>=1.20.0 # Apache-2.0
 
 reno>=2.5.0 # Apache-2.0

tox.ini

@@ -1,10 +1,11 @@
 [tox]
 minversion = 3.1.0
-envlist = py3,py27,pep8
+envlist = py3,pep8
 skipsdist = True
 ignore_basepython_conflict=true
 
 [testenv]
+basepython = python3
 usedevelop = True
 install_command = pip install {opts} {packages}
 setenv =
@@ -15,29 +16,23 @@ deps = -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/
 commands = python setup.py test --slowest --testr-args='{posargs}'
 
 [testenv:pep8]
-basepython = python3
 commands = flake8 {posargs}
 
 [testenv:venv]
-basepython = python3
 commands = {posargs}
 
 [testenv:cover]
-basepython = python3
 commands = python setup.py test --coverage --testr-args='{posargs}'
 
 [testenv:docs]
-basepython = python3
 commands = python setup.py build_sphinx
 
 [testenv:pdf-docs]
-basepython = python3
 whitelist_externals = make
 commands = sphinx-build -b latex doc/source doc/build/pdf
            make -C doc/build/pdf
 
 [testenv:debug]
-basepython = python3
 commands = oslo_debug_helper {posargs}
 
 [flake8]

zuul.d/stable-jobs.yaml

@@ -4,7 +4,7 @@
     override-checkout: stable/train
     vars:
       devstack_localrc:
-        USE_PYTHON3: False
+        USE_PYTHON3: True
 
 - job:
     name: ironic-standalone-stein
@@ -12,7 +12,7 @@
     override-checkout: stable/stein
     vars:
       devstack_localrc:
-        USE_PYTHON3: False
+        USE_PYTHON3: True
 
 - job:
     name: ironic-tempest-functional-python3-train
@@ -31,7 +31,7 @@
     override-checkout: stable/train
     vars:
       devstack_localrc:
-        USE_PYTHON3: False
+        USE_PYTHON3: True
 
 - job:
     name: ironic-tempest-ipa-wholedisk-direct-tinyipa-multinode-stein
@@ -39,7 +39,7 @@
     override-checkout: stable/stein
     vars:
       devstack_localrc:
-        USE_PYTHON3: False
+        USE_PYTHON3: True
 
 - job:
     name: ironic-inspector-tempest-train
@@ -49,7 +49,7 @@
       devstack_localrc:
         FIXED_NETWORK_SIZE: 4096
         EBTABLES_RACE_FIX: True
-        USE_PYTHON3: False
+        USE_PYTHON3: True
 
 - job:
     name: ironic-inspector-tempest-stein
@@ -59,7 +59,7 @@
       devstack_localrc:
         FIXED_NETWORK_SIZE: 4096
         EBTABLES_RACE_FIX: True
-        USE_PYTHON3: False
+        USE_PYTHON3: True
 
 - job:
     name: ironic-inspector-tempest-discovery-train
@@ -67,7 +67,7 @@
     override-checkout: stable/train
     vars:
       devstack_localrc:
-        USE_PYTHON3: False
+        USE_PYTHON3: True
 
 - job:
     name: ironic-inspector-tempest-discovery-stein
@@ -75,4 +75,4 @@
     override-checkout: stable/stein
     vars:
       devstack_localrc:
-        USE_PYTHON3: False
+        USE_PYTHON3: True