Merge pull request #34 from vikingco/pre-django-1.8-merge-master

Trying to merge the branches

README.rst

@@ -45,6 +45,9 @@ Wishlist
 
 Releases
 --------
+v2.0.0:
+  Merging of master and pre-django-1.8 branches
+  Removes management command in favor of a celery task
 v1.2.1:
   Fix problem in migration to UUIDField for PostGres
 v1.2.0:

circle.yml

@@ -2,6 +2,10 @@ machine:
     python:
         version: 2.7.6
 
+dependencies:
+    override:
+        - pip install -U tox virtualenv
+
 test:
     override:
         - tox

deployment/requirements_test.txt

@@ -2,3 +2,5 @@ Django
 freezegun
 tox
 coverage
+celery
+amqp>=1.3.0,<2.1.0

locking/__init__.py

@@ -1 +1 @@
-__version__ = '1.2.1'
+__version__ = '2.0.0'

locking/admin.py

@@ -6,4 +6,6 @@
 class NonBlockingLockAdmin(admin.ModelAdmin):
     date_hierarchy = 'created_on'
     list_display = ('locked_object', 'created_on')
+
+
 admin.site.register(NonBlockingLock, NonBlockingLockAdmin)

locking/migrations/0004_auto_20160907_0942.py

@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.9.7 on 2016-09-07 09:42
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('locking', '0003_optimize_queries'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='nonblockinglock',
+            name='max_age',
+            field=models.PositiveIntegerField(default=600, help_text='The age of a lock before it can be overwritten. 0 means indefinitely.', verbose_name='Maximum lock age'),
+        ),
+    ]

locking/migrations/0005_merge_20170504_1024.py

@@ -0,0 +1,16 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11 on 2017-05-04 10:24
+from __future__ import unicode_literals
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('locking', '0004_auto_20160907_0942'),
+        ('locking', '0004_auto_20151115_0703'),
+    ]
+
+    operations = [
+    ]

locking/models.py

@@ -3,7 +3,7 @@
 from datetime import timedelta
 
 from django.utils import timezone
-from django.db import models, IntegrityError
+from django.db import models, IntegrityError, transaction
 from django.db.models import Q
 from django.db.models.signals import pre_save
 from django.dispatch import receiver
@@ -50,21 +50,30 @@ def acquire_lock(self, obj=None, max_age=None, lock_name=''):
         if obj is not None:
             lock_name = _get_lock_name(obj)
 
-        try:
-            lock, created = self.get_or_create(locked_object=lock_name,
-                                               defaults={'max_age': max_age})
-            if not created:
-                # check whether lock is expired
-                if lock.is_expired:
-                    # Create a new lock to provide a new id for renewal.
-                    # This ensures the owner of the previous lock doesn't
-                    # remain in possession of the active lock id.
-                    lock.release()
-                    lock = self.create(locked_object=lock_name, max_age=max_age)
-                else:
-                    raise AlreadyLocked()
-        except IntegrityError:
-            raise AlreadyLocked()
+        with transaction.atomic():
+            try:
+                now = timezone.now()
+
+                defaults = {'max_age': max_age,
+                            'created_on': now,
+                            'renewed_on': now,
+                            'expires_on': now + timedelta(seconds=max_age)}
+
+                lock, created = self.get_or_create(locked_object=lock_name,
+                                                   defaults=defaults)
+                if not created:
+                    # check whether lock is expired
+                    if lock.is_expired:
+                        # Create a new lock to provide a new id for renewal.
+                        # This ensures the owner of the previous lock doesn't
+                        # remain in possession of the active lock id.
+                        lock.release()
+                        lock = self.create(locked_object=lock_name, max_age=max_age)
+                    else:
+                        raise AlreadyLocked()
+
+            except IntegrityError:
+                raise AlreadyLocked()
 
         return lock
 

locking/tasks.py

@@ -0,0 +1,11 @@
+from celery import shared_task
+
+from .models import NonBlockingLock
+
+
+@shared_task
+def clean_expired_locks():
+    """
+    Delete all expired locks.
+    """
+    NonBlockingLock.objects.get_expired_locks().delete()

locking/tests.py

@@ -5,13 +5,12 @@
 
 from freezegun import freeze_time
 
-from django.core.management import call_command
-from django.test import TestCase
-
 from django.contrib.auth.models import User
+from django.test import TestCase
 
 from .exceptions import AlreadyLocked, RenewalError
 from .models import NonBlockingLock, _get_lock_name
+from .tasks import clean_expired_locks
 
 
 class NonBlockingLockTest(TestCase):
@@ -122,15 +121,16 @@ def test_context_manager(self):
 
 
 class CleanExpiredLocksTest(TestCase):
+    """Tests correct functioning of the task that cleans expired locks."""
     def setUp(self):
-        self.user = User.objects.create(username='CleanExpiredLocks test')
+        self.user = User.objects.create(username='hellofoo')
 
-    def test_clean_locks(self):
+    def test_clean(self):
+        """Make expired lock, ensure the management command cleans it up."""
         with freeze_time("2015-01-01 10:00"):
-            NonBlockingLock.objects.acquire_lock(self.user, max_age=1)
-
-        self.assertEqual(1, NonBlockingLock.objects.get_expired_locks().count())
-        call_command('clean_expired_locks', dry_run=True)
-        self.assertEqual(1, NonBlockingLock.objects.get_expired_locks().count())
-        call_command('clean_expired_locks')
-        self.assertEqual(0, NonBlockingLock.objects.get_expired_locks().count())
+            lock_to_be_released = NonBlockingLock.objects.acquire_lock(self.user, max_age=0)
+            NonBlockingLock.objects.acquire_lock(lock_to_be_released, max_age=1)
+        with freeze_time("2015-01-01 11:00"):
+            # Only the non-expired lock should remain
+            clean_expired_locks()
+            self.assertEqual(NonBlockingLock.objects.get(), lock_to_be_released)

setup.py

@@ -39,7 +39,7 @@ def run_tests(self):
     author='VikingCo',
     packages=find_packages('.'),
     cmdclass={'test': RunTestsCommand},
-    tests_require=['django', 'freezegun'],
+    tests_require=['django', 'freezegun', 'celery'],
     classifiers=[
         'Intended Audience :: Developers',
         'Programming Language :: Python',

test_project/test_project/urls.py

@@ -17,5 +17,5 @@
 from django.contrib import admin
 
 urlpatterns = [
-    url(r'^admin/', include(admin.site.urls)),
+    url(r'^admin/', admin.site.urls),
 ]