Django 4.0 and Python 3.10 support (#528)

* Replaced pytz with zoneinfo

* Fixed tests

* Added Python 3.10 to test suite

* Removed now-redundant testing requirement

* Bumped minimum django-timezone-field version

* Upgraded pytest

* Addressed points made in the PR

* Added Python 3.10 environment to GitHub Actions

* Removed pytz from new test

* Fixed test

* Added RabbitMQ to GitHub Actions

* Fixed apicheck and linkcheck calling wrong Django version

* Fixed flake8 woes

* Fixed Sphinx generation warnings

Co-authored-by: Bruno Marques <[email protected]>

.github/workflows/test.yml

@@ -12,7 +12,13 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ['3.7', '3.8', '3.9', 'pypy-3.9']
+        python-version: ['3.7', '3.8', '3.9', '3.10', 'pypy-3.9']
+
+    services:
+      rabbitmq:
+        image: rabbitmq
+        ports:
+          - "5672:5672"
 
     steps:
     - uses: actions/checkout@v3

README.rst

@@ -46,7 +46,7 @@ Important Warning about Time Zones
 
 
 
-.. note:: 
+.. note::
    This will reset the state as if the periodic tasks have never run before.
 
 
@@ -95,7 +95,7 @@ create the interval object:
 .. code-block:: Python
 
         >>> from django_celery_beat.models import PeriodicTask, IntervalSchedule
-        
+
         # executes every 10 seconds.
         >>> schedule, created = IntervalSchedule.objects.get_or_create(
         ...     every=10,
@@ -181,7 +181,7 @@ of a ``30 * * * *`` (execute every 30 minutes) crontab entry you specify:
         ...     day_of_week='*',
         ...     day_of_month='*',
         ...     month_of_year='*',
-        ...     timezone=pytz.timezone('Canada/Pacific')
+        ...     timezone=zoneinfo.ZoneInfo('Canada/Pacific')
         ... )
 
 The crontab schedule is linked to a specific timezone using the 'timezone' input parameter.
@@ -288,7 +288,7 @@ After installation, add ``django_celery_beat`` to Django's settings module:
 Run the ``django_celery_beat`` migrations using:
 
 .. code-block:: bash
-    
+
         $ python manage.py migrate django_celery_beat
 
 

django_celery_beat/migrations/0016_alter_crontabschedule_timezone.py

@@ -0,0 +1,25 @@
+# Generated by Django 4.0.3 on 2022-03-21 20:20
+# flake8: noqa
+from django.db import migrations
+import django_celery_beat.models
+import timezone_field.fields
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('django_celery_beat', '0015_edit_solarschedule_events_choices'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='crontabschedule',
+            name='timezone',
+            field=timezone_field.fields.TimeZoneField(
+                default=
+                django_celery_beat.models.crontab_schedule_celery_timezone,
+                help_text=
+                'Timezone to Run the Cron Schedule on. Default is UTC.',
+                use_pytz=False, verbose_name='Cron Timezone'),
+        ),
+    ]

django_celery_beat/models.py

@@ -1,4 +1,8 @@
 """Database models."""
+try:
+    from zoneinfo import available_timezones
+except ImportError:
+    from backports.zoneinfo import available_timezones
 from datetime import timedelta
 
 import timezone_field
@@ -66,10 +70,9 @@ def crontab_schedule_celery_timezone():
             settings, '%s_TIMEZONE' % current_app.namespace)
     except AttributeError:
         return 'UTC'
-    return CELERY_TIMEZONE if CELERY_TIMEZONE in [
-        choice[0].zone for choice in timezone_field.
-        TimeZoneField.default_choices
-    ] else 'UTC'
+    if CELERY_TIMEZONE in available_timezones():
+        return CELERY_TIMEZONE
+    return 'UTC'
 
 
 class SolarSchedule(models.Model):
@@ -297,6 +300,7 @@ class CrontabSchedule(models.Model):
 
     timezone = timezone_field.TimeZoneField(
         default=crontab_schedule_celery_timezone,
+        use_pytz=False,
         verbose_name=_('Cron Timezone'),
         help_text=_(
             'Timezone to Run the Cron Schedule on. Default is UTC.'),
@@ -357,8 +361,8 @@ def from_schedule(cls, schedule):
 class PeriodicTasks(models.Model):
     """Helper table for tracking updates to periodic tasks.
 
-    This stores a single row with ``ident=1``.  ``last_update`` is updated
-    via django signals whenever anything is changed in the :class:`~.PeriodicTask` model.
+    This stores a single row with ``ident=1``. ``last_update`` is updated via
+    signals whenever anything changes in the :class:`~.PeriodicTask` model.
     Basically this acts like a DB data audit trigger.
     Doing this so we also track deletions, and not just insert/update.
     """

django_celery_beat/schedulers.py

@@ -136,12 +136,8 @@ def is_due(self):
         return self.schedule.is_due(last_run_at_in_tz)
 
     def _default_now(self):
-        # The PyTZ datetime must be localised for the Django-Celery-Beat
-        # scheduler to work. Keep in mind that timezone arithmatic
-        # with a localized timezone may be inaccurate.
         if getattr(settings, 'DJANGO_CELERY_BEAT_TZ_AWARE', True):
-            now = self.app.now()
-            now = now.tzinfo.localize(now.replace(tzinfo=None))
+            now = datetime.datetime.now(self.app.timezone)
         else:
             # this ends up getting passed to maybe_make_aware, which expects
             # all naive datetime objects to be in utc time.

django_celery_beat/tzcrontab.py

@@ -2,8 +2,7 @@
 from celery import schedules
 
 from collections import namedtuple
-from datetime import datetime
-import pytz
+from datetime import datetime, timezone
 
 
 schedstate = namedtuple('schedstate', ('is_due', 'next'))
@@ -14,7 +13,7 @@ class TzAwareCrontab(schedules.crontab):
 
     def __init__(
             self, minute='*', hour='*', day_of_week='*',
-            day_of_month='*', month_of_year='*', tz=pytz.utc, app=None
+            day_of_month='*', month_of_year='*', tz=timezone.utc, app=None
     ):
         """Overwrite Crontab constructor to include a timezone argument."""
         self.tz = tz
@@ -28,9 +27,7 @@ def __init__(
         )
 
     def nowfunc(self):
-        return self.tz.normalize(
-            pytz.utc.localize(datetime.utcnow())
-        )
+        return datetime.now(self.tz)
 
     def is_due(self, last_run_at):
         """Calculate when the next run will take place.

docs/conf.py

@@ -24,12 +24,12 @@
     ],
     extlinks={
       'github_project': (
-        f'https://github.com/%s',
-        'GitHub project',
+        'https://github.com/%s',
+        'GitHub project %s',
       ),
       'github_pr': (
-        f'https://github.com/celery/django-celery-beat/pull/%s',
-        'GitHub PR #',
+        'https://github.com/celery/django-celery-beat/pull/%s',
+        'GitHub PR #%s',
       ),
     },
     extra_intersphinx_mapping={

requirements/default.txt

@@ -1,3 +1,5 @@
 celery>=5.2.3,<6.0
-django-timezone-field>=4.2.3
+django-timezone-field>=5.0
+backports.zoneinfo; python_version<"3.9"
+tzdata
 python-crontab>=2.3.4

requirements/test.txt

@@ -1,6 +1,5 @@
 case>=1.3.1
-pytest-django<5.0
-pytz>dev
-pytest<8.0
+pytest-django>=2.2,<5.0
+pytest>=6.2.5,<8.0
 pytest-timeout
 ephem

setup.py

@@ -38,11 +38,12 @@ def _pyimp():
     Programming Language :: Python :: 3.7
     Programming Language :: Python :: 3.8
     Programming Language :: Python :: 3.9
+    Programming Language :: Python :: 3.10
     Programming Language :: Python :: Implementation :: CPython
     Programming Language :: Python :: Implementation :: PyPy
     Framework :: Django
-    Framework :: Django :: 4.0
     Framework :: Django :: 3.2
+    Framework :: Django :: 4.0
     Operating System :: OS Independent
     Topic :: Communications
     Topic :: System :: Distributed Computing

t/proj/urls.py

@@ -2,5 +2,5 @@
 from django.urls import path
 
 urlpatterns = [
-     path('admin/', admin.site.urls),
+    path('admin/', admin.site.urls),
 ]

t/unit/test_models.py

@@ -1,4 +1,9 @@
+import datetime
 import os
+try:
+    from zoneinfo import available_timezones, ZoneInfo
+except ImportError:
+    from backports.zoneinfo import available_timezones, ZoneInfo
 
 from celery import schedules
 from django.test import TestCase, override_settings
@@ -9,8 +14,6 @@
 from django.db.migrations.questioner import NonInteractiveMigrationQuestioner
 from django.utils import timezone
 from django.conf import settings
-import pytz, datetime
-import timezone_field
 
 from django_celery_beat import migrations as beat_migrations
 from django_celery_beat.models import (
@@ -84,8 +87,7 @@ def _test_duplicate_schedules(self, cls, kwargs, schedule=None):
 
 
 class CrontabScheduleTestCase(TestCase, TestDuplicatesMixin):
-    FIRST_VALID_TIMEZONE = timezone_field.\
-        TimeZoneField.default_choices[0][0].zone
+    FIRST_VALID_TIMEZONE = available_timezones().pop()
 
     def test_default_timezone_without_settings_config(self):
         assert crontab_schedule_celery_timezone() == "UTC"
@@ -148,11 +150,12 @@ def test_duplicate_schedules(self):
         kwargs = {'clocked_time': timezone.now()}
         self._test_duplicate_schedules(ClockedSchedule, kwargs)
 
-    # IMPORTANT: we must have a valid time-zone (not UTC) to do an accurate testing
-    @override_settings(TIME_ZONE='Africa/Cairo') 
+    # IMPORTANT: we must have a valid timezone (not UTC) for accurate testing
+    @override_settings(TIME_ZONE='Africa/Cairo')
     def test_timezone_format(self):
-        """Make sure the scheduled time is not shown in UTC when time zone is used"""
-        tz_info = pytz.timezone(settings.TIME_ZONE).localize(datetime.datetime.utcnow())
-        schedule, created = ClockedSchedule.objects.get_or_create(clocked_time=tz_info)
+        """Ensure scheduled time is not shown in UTC when timezone is used"""
+        tz_info = datetime.datetime.now(ZoneInfo(settings.TIME_ZONE))
+        schedule, created = ClockedSchedule.objects.get_or_create(
+            clocked_time=tz_info)
         # testnig str(schedule) calls make_aware() internally
         assert str(schedule.clocked_time) == str(schedule)

tox.ini

@@ -3,18 +3,20 @@ python =
     3.7: py37
     3.8: py38, apicheck, linkcheck
     3.9: py39, flake8, pydocstyle, cov
+    3.10: py310
     pypy-3.9: pypy3
 
 [gh-actions:env]
 DJANGO =
     3.2: django32
     4.0: django40
-    
+
 [tox]
 envlist =
     py37-django{32}
     py38-django{32,40}
     py39-django{32,40}
+    py310-django{32,40}
     pypy3-django{32}
     flake8
     apicheck
@@ -43,12 +45,12 @@ commands =
 
 
 [testenv:apicheck]
-basepython = python3.9
+basepython = python3.8
 commands =
     sphinx-build -W -b apicheck -d {envtmpdir}/doctrees docs docs/_build/apicheck
 
 [testenv:linkcheck]
-basepython = python3.9
+basepython = python3.8
 commands =
     sphinx-build -W -b linkcheck -d {envtmpdir}/doctrees docs docs/_build/linkcheck