add black configuration (#52457)

.git-blame-ignore-revs

@@ -0,0 +1,2 @@
+# misc: apply black
+4bb33d3d3c62516cfdb1ff5bba9216936a07d368

.pre-commit-config.yaml

@@ -0,0 +1,8 @@
+# See https://pre-commit.com for more information
+# See https://pre-commit.com/hooks.html for more hooks
+repos:
+-   repo: https://github.com/psf/black
+    rev: 20.8b1
+    hooks:
+    - id: black
+      args: ['--target-version', 'py37', '--skip-string-normalization', '--line-length', '110']

Jenkinsfile

@@ -14,7 +14,7 @@ pipeline {
                 sh """
 python3 -m venv ${env.TMPDIR}/venv/
 ${env.TMPDIR}/venv/bin/pip install tox
-PGPORT=`python -c 'import struct; import socket; s=socket.socket(); s.setsockopt(socket.SOL_SOCKET, socket.SO_LINGER, struct.pack("ii", 1, 0)); s.bind(("", 0)); print(s.getsockname()[1]); s.close()'` pg_virtualenv -o fsync=off ${env.TMPDIR}/venv/bin/tox -rv -e rbac-py3-dj111,authentic-py3-dj111-drf39,authentic-py3-dj22-drf39,pylint"""
+PGPORT=`python -c 'import struct; import socket; s=socket.socket(); s.setsockopt(socket.SOL_SOCKET, socket.SO_LINGER, struct.pack("ii", 1, 0)); s.bind(("", 0)); print(s.getsockname()[1]); s.close()'` pg_virtualenv -o fsync=off ${env.TMPDIR}/venv/bin/tox -rv -e code-style,rbac-py3-dj111,authentic-py3-dj111-drf39,authentic-py3-dj22-drf39,pylint"""
             }
             post {
                 always {

README

@@ -68,6 +68,16 @@ Upgrade
    using a previous one you must first upgrade to 2.1.12 before tempting
    upgrade to a release later than 2.2.0.
 
+Code Style
+==========
+
+black is used to format the code, using thoses parameters:
+
+    black --target-version py37 --skip-string-normalization --line-length 110
+
+There is .pre-commit-config.yaml to use pre-commit to automatically run black
+before commits. (execute `pre-commit install` to install the git hook.)
+
 Support
 =======
 

tox.ini

@@ -6,6 +6,7 @@
 [tox]
 toxworkdir = {env:TMPDIR:/tmp}/tox-{env:USER}/authentic/
 envlist =
+  code-style
   authentic-py3-dj111-drf39
   authentic-py3-dj22-drf39
 
@@ -106,6 +107,13 @@ commands =
     ./getlasso3.sh
     ./authentic2-ctl {posargs:--help}
 
+[testenv:code-style]
+skip_install = true
+deps =
+  pre-commit
+commands =
+  pre-commit run black --all-files --show-diff-on-failure
+
 [pytest]
 filterwarnings =
   ignore