Refactor managemails to use signals

- use signals to trigger Celery tasks to create and delete mailboxes
- add generic TestCaseWithCeleryTasks class to handle celery task tests
  in a uniform way

gnuviechadmin/managemails/apps.py

@@ -15,3 +15,11 @@ class ManageMailsAppConfig(AppConfig):
 
     name = "managemails"
     verbose_name = _("Mailboxes and Mail Addresses")
+
+    def ready(self):
+        """
+        Takes care of importing the signal handlers of the :py:mod:`userdbs`
+        app.
+
+        """
+        import managemails.signals  # NOQA

gnuviechadmin/managemails/models.py

@@ -8,7 +8,6 @@ from model_utils.models import TimeStampedModel
 from passlib.handlers.sha2_crypt import sha512_crypt
 
 from domains.models import MailDomain
-from fileservertasks.tasks import create_file_mailbox, delete_file_mailbox
 from osusers.models import User as OsUser
 
 
@@ -123,16 +122,6 @@ class Mailbox(ActivateAbleMixin, TimeStampedModel):
         """
         self.password = sha512_crypt.hash(password)
 
-    def save(self, *args, **kwargs):
-        # TODO: refactor to use signals
-        create_file_mailbox.delay(self.osuser.username, self.username).get()
-        super(Mailbox, self).save(*args, **kwargs)
-
-    def delete(self, *args, **kwargs):
-        # TODO: refactor to use signals
-        delete_file_mailbox.delay(self.osuser.username, self.username).get()
-        super(Mailbox, self).delete(*args, **kwargs)
-
     def get_mailaddresses(self):
         """
         Get a list of mail addresses assigned to this mailbox.

gnuviechadmin/managemails/signals.py

@@ -0,0 +1,62 @@
+"""
+This module contains the signal handlers of the :py:mod:`managemails` app.
+
+The module starts Celery_ tasks.
+
+.. _Celery: https://www.celeryproject.org/
+
+"""
+import logging
+
+from django.db.models.signals import post_delete, post_save
+from django.dispatch import receiver
+
+from fileservertasks.tasks import create_file_mailbox, delete_file_mailbox
+from managemails.models import Mailbox
+from taskresults.models import TaskResult
+
+_LOGGER = logging.getLogger(__name__)
+
+
+@receiver(post_save, sender=Mailbox)
+def handle_mailbox_created(sender, instance, created, **kwargs):
+    """
+    Handles post creation actions on :py:class:`Mailbox <managemails.models.Mailbox>` instances.
+
+    :param sender: sender of the signal
+    :param instance: Mailbox instance
+    :param created: whether the instance has just been created
+
+    This signal handler starts a Celery_ task.
+
+    """
+    if created:
+        taskresult = TaskResult.objects.create_task_result(
+            "handle_mailbox_created",
+            create_file_mailbox.s(instance.osuser.username, instance.username),
+        )
+        _LOGGER.info(
+            "Mailbox creation has been requested in task %s", taskresult.task_id
+        )
+    _LOGGER.debug("mailbox %s has been %s", instance, created and "created" or "updated")
+
+
+@receiver(post_delete, sender=Mailbox)
+def handle_mailbox_deleted(sender, instance, **kwargs):
+    """
+    Handles cleanup actions to be done after deletion of a
+    :py:class:`Mailbox <managemails.models.Mailbox>` instance.
+
+    :param sender: sender of the signal
+    :param instance: Mailbox instance
+
+    This signal handler starts a Celery_ task.
+
+    """
+    taskresult = TaskResult.objects.create_task_result(
+        "handle_mailbox_deleted",
+        delete_file_mailbox.s(instance.osuser.username, instance.username)
+    )
+    _LOGGER.info(
+        "Mailbox deletion has been requested in task %s", taskresult.task_id
+    )

gnuviechadmin/managemails/tests/test_models.py

@@ -1,24 +1,20 @@
 """
 This module contains tests for :py:mod:`managemails.models`
 """
-from unittest.mock import patch
-
 from django.contrib.auth import get_user_model
 from django.test import TestCase, TransactionTestCase
 from django.test.utils import override_settings
-from passlib.hash import sha512_crypt
+from passlib.handlers.sha2_crypt import sha512_crypt
 
 from domains.models import MailDomain
 from managemails.models import MailAddress, Mailbox
 from osusers.models import User
+from taskresults.tests.testutils import TestCaseWithCeleryTasks
 
 Customer = get_user_model()
 
 
-@override_settings(
-    CELERY_ALWAYS_EAGER=True, CELERY_CACHE_BACKEND="memory", BROKER_BACKEND="memory"
-)
-class MailboxTest(TestCase):
+class MailboxTest(TestCaseWithCeleryTasks):
     def setUp(self):
         super(MailboxTest, self).setUp()
         self.customer = Customer.objects.create_user("test")
@@ -35,22 +31,32 @@ class MailboxTest(TestCase):
         mb.set_password("test")
         self.assertEqual(str(mb), "test")
 
-    @patch("managemails.models.create_file_mailbox")
-    def test_save(self, create_file_mailbox_task):
+    def test_save(self):
         user = User.objects.create_user(self.customer)
+
+        self.resetCeleryTasks()
+
         mb = Mailbox.objects.create_mailbox(user)
         self.assertIsNotNone(mb.pk)
-        create_file_mailbox_task.delay.assert_called_with(user.username, mb.username)
 
-    @patch("managemails.models.delete_file_mailbox")
-    def test_delete(self, delete_file_mailbox_task):
+        self.assertCeleryTasksRun([
+            (1, "handle_mailbox_created"),
+        ])
+
+    def test_delete(self):
         user = User.objects.create_user(self.customer)
         mb = Mailbox.objects.create_mailbox(user)
+
+        self.resetCeleryTasks()
+
         mb.delete()
         self.assertIsNone(mb.pk)
-        delete_file_mailbox_task.delay.assert_called_with(user.username, mb.username)
 
-    def test_get_mailaddresses(self):
+        self.assertCeleryTasksRun([
+            (1, "handle_mailbox_deleted"),
+        ])
+
+    def test_get_mail_addresses(self):
         user = User.objects.create_user(self.customer)
         mb = Mailbox.objects.create_mailbox(user)
         md = MailDomain.objects.create(domain="example.org")
@@ -61,10 +67,7 @@ class MailboxTest(TestCase):
         self.assertIn(address, mailaddresses)
 
 
-@override_settings(
-    CELERY_ALWAYS_EAGER=True, CELERY_CACHE_BACKEND="memory", BROKER_BACKEND="memory"
-)
-class MailAddressTest(TransactionTestCase):
+class MailAddressTest(TestCaseWithCeleryTasks):
     def test__str__(self):
         md = MailDomain.objects.create(domain="example.org")
         ma = MailAddress.objects.create(localpart="test", domain=md)
@@ -214,10 +217,7 @@ class MailAddressTest(TransactionTestCase):
         self.assertEqual(mafwds[0].target, "test2@example.org")
 
 
-@override_settings(
-    CELERY_ALWAYS_EAGER=True, CELERY_CACHE_BACKEND="memory", BROKER_BACKEND="memory"
-)
-class MailboxManagerTest(TransactionTestCase):
+class MailboxManagerTest(TestCaseWithCeleryTasks):
     def setUp(self):
         super(MailboxManagerTest, self).setUp()
         self.customer = Customer.objects.create_user("test")
@@ -302,10 +302,7 @@ class MailboxManagerTest(TransactionTestCase):
         self.assertTrue(sha512_crypt.verify("test", mailbox.password))
 
 
-@override_settings(
-    CELERY_ALWAYS_EAGER=True, CELERY_CACHE_BACKEND="memory", BROKER_BACKEND="memory"
-)
-class MailAddressMailboxTest(TestCase):
+class MailAddressMailboxTest(TestCaseWithCeleryTasks):
     def setUp(self):
         super(MailAddressMailboxTest, self).setUp()
         self.customer = Customer.objects.create_user("test")

gnuviechadmin/taskresults/tests/testutils.py

@@ -0,0 +1,21 @@
+from django.test import TestCase
+from django.test.utils import override_settings
+
+from taskresults.models import TaskResult
+
+
+@override_settings(
+    CELERY_ALWAYS_EAGER=True, CELERY_CACHE_BACKEND="memory", BROKER_BACKEND="memory"
+)
+class TestCaseWithCeleryTasks(TestCase):
+    def resetCeleryTasks(self):
+        TaskResult.objects.all().delete()
+
+    def assertCeleryTasksRun(self, tasks):
+        task_results = TaskResult.objects.all()
+
+        self.assertEqual(task_results.count(), sum([t[0] for t in tasks]))
+
+        creators = [r.creator for r in task_results]
+        for t_count, t_creator in tasks:
+            self.assertEqual(creators.count(t_creator), t_count)