Add flake8-import-order and use python3.9 on tox

Improving the code quality of upstream by adding the flake8 check on
zuul and adding the flake8-import-order plugin to standardize imports.
Also, defaults testenv to python3.9 configuration that should be used
for now on with the debian migration.

Story: 2010100
Task: 45669
Signed-off-by: Thiago Brito <thiago.brito@windriver.com>
Change-Id: I55aa952c4f22a7af53e1f1c11a4a51997afa4bcf

.zuul.yaml

@@ -5,16 +5,26 @@
       - stx-release-notes-jobs
     check:
       jobs:
-        - openstack-tox-pep8
-        - openstack-tox-linters
+        - stx-upstream-tox-pep8
+        - stx-upstream-tox-linters
     gate:
       jobs:
-        - openstack-tox-pep8
-        - openstack-tox-linters
+        - stx-upstream-tox-pep8
+        - stx-upstream-tox-linters
     post:
       jobs:
         - stx-upstream-upload-git-mirror
 
+- job:
+    name: stx-upstream-tox-pep8
+    parent: openstack-tox-pep8
+    nodeset: debian-bullseye
+
+- job:
+    name: stx-upstream-tox-linters
+    parent: openstack-tox-linters
+    nodeset: debian-bullseye
+
 - job:
     name: stx-upstream-upload-git-mirror
     parent: upload-git-mirror

openstack/python-horizon/centos/files/guni_config.py

@@ -3,6 +3,7 @@ import fnmatch
 import os
 import resource
 import subprocess
+
 from django.conf import settings
 
 

openstack/python-keystone/centos/files/public.py

@@ -12,10 +12,11 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
+import sys
 
 from keystone.server import wsgi as wsgi_server
 
-import sys
+
 sys.argv = sys.argv[:1]
 
 application = wsgi_server.initialize_public_application()

test-requirements.txt

@@ -1,4 +1,5 @@
-bashate >= 0.2
-PyYAML >= 3.1.0
-yamllint >= 0.5.2
-flake8 >= 2.5.4 # MIT
+bashate
+PyYAML
+yamllint
+flake8
+flake8-import-order

tox.ini

@@ -4,7 +4,12 @@ minversion = 2.3
 skipsdist = True
 
 [testenv]
-install_command = pip install -U {opts} {packages}
+basepython = python3.9
+install_command = pip install \
+    -v -v -v \
+    -U \
+    -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/starlingx/root/raw/branch/master/build-tools/requirements/debian/upper-constraints.txt} \
+    {opts} {packages}
 setenv = VIRTUAL_ENV={envdir}
          OS_STDOUT_CAPTURE=1
          OS_STDERR_CAPTURE=1
@@ -12,7 +17,6 @@ setenv = VIRTUAL_ENV={envdir}
 deps = -r{toxinidir}/test-requirements.txt
 
 [testenv:linters]
-basepython = python3
 whitelist_externals = bash
 commands =
   bash -c "find {toxinidir}          \
@@ -27,8 +31,18 @@ commands =
             -o -name '*.yaml'       \
             -print0 | xargs -0 yamllint"
 
+[flake8]
+# E123, E125 skipped as they are invalid PEP-8.
+# E501 skipped because some of the code files include templates
+#      that end up quite wide
+# H405: multi line docstring summary not separated with an empty line
+show-source = True
+ignore = E123,E125,E501,H405
+exclude = .venv,.git,.tox,dist,doc,*lib/python*,*egg,build,release-tag-*
+import-order-style = google
+
+
 [testenv:pep8]
-basepython = python3
 usedevelop = False
 description =
           Run style checks.
@@ -38,18 +52,7 @@ commands =
           flake8
 
 
-[flake8]
-# E123, E125 skipped as they are invalid PEP-8.
-# E501 skipped because some of the code files include templates
-#      that end up quite wide
-# H405: multi line docstring summary not separated with an empty line
-show-source = True
-ignore = E123,E125,E501,H405
-exclude = .venv,.git,.tox,dist,doc,*lib/python*,*egg,build,release-tag-*
-
-
 [testenv:venv]
-basepython = python3
 commands = {posargs}
 
 [testenv:docs]
@@ -71,8 +74,8 @@ whitelist_externals =
     reno
 
 [testenv:newnote]
-basepython = python3
 # Re-use the releasenotes venv
+basepython = python3
 envdir = {toxworkdir}/releasenotes
 deps = -r{toxinidir}/doc/requirements.txt
 commands = reno new {posargs}