Remove task scheduler

We have switched to using Django Q for queuing tasks so the task
scheduler can be removed. A future commit will reintroduce queing of
notifications on the end date of roles.

greg/management/commands/task_scheduler.py

-import logging
-import logging.config
-import time
-
-from django.conf import settings
-from django.core.management.base import BaseCommand
-
-from greg.schedule import ExpiringRolesNotification
-
-logging.config.dictConfig(settings.LOGGING)
-logger = logging.getLogger(__name__)
-
-
-class Command(BaseCommand):
-    """
-    This command starts a basic task runner. All tasks it is supposed to
-    run are given explicitly in code
-    """
-
-    help = "Start schedule task runner"
-
-    def handle(self, *args, **options):
-
-        logger.info("Task scheduler started")
-
-        # For now there is just one task, but the idea is that more can
-        # be added
-        expiring_role_notification_task = ExpiringRolesNotification()
-
-        while True:
-            expiring_role_notification_task.run()
-            # The single task is set up for far only needs to run once
-            # a day, but running every 6 hours just in case a run fails,
-            # it is up the task it self to figure out if needs to do
-            # something every time it is called
-            time.sleep(60 * 60 * 6)

greg/migrations/0013_delete_scheduletask.py

+# Generated by Django 3.2.8 on 2021-11-04 10:02
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("greg", "0012_ou_identifiers"),
+    ]
+
+    operations = [
+        migrations.DeleteModel(
+            name="ScheduleTask",
+        ),
+    ]

greg/models.py

@@ -469,20 +469,6 @@ class SponsorOrganizationalUnit(BaseModel):
         )
 
 
-class ScheduleTask(models.Model):
-    """
-    Stores information about a task
-    """
-
-    name = models.CharField(max_length=32)
-    last_completed = models.DateTimeField(null=True)
-
-    def __repr__(self):
-        return "{}(id={!r}, name={!r}, last_completed={!r})".format(
-            self.__class__.__name__, self.pk, self.name, self.last_completed
-        )
-
-
 class InvitationLink(BaseModel):
     """
     Link to an invitation.

greg/schedule.py

-import time
-from datetime import date, datetime, timedelta
-from typing import Optional
-
-from abc import ABC, abstractmethod
-from django.utils import timezone
-
-from greg.models import Role, Notification, ScheduleTask
-
-
-class BaseSchedule(ABC):
-    """
-    Provides common methods for tasks
-    """
-
-    task_object: ScheduleTask
-
-    def __init__(self, name: str):
-        self.task_object = ScheduleTask.objects.get(name=name)
-
-    def run(self):
-        self._run_internal()
-        self.task_object.last_completed = timezone.now()
-        self.task_object.save()
-
-    @abstractmethod
-    def _run_internal(self):
-        pass
-
-    def get_last_run(self) -> Optional[datetime]:
-        self.task_object.refresh_from_db()
-        return self.task_object.last_completed
-
-    def _store_notification(
-        self, identifier, object_type, operation, **kwargs
-    ) -> Notification:
-        return Notification.objects.create(
-            identifier=identifier,
-            object_type=object_type,
-            operation=operation,
-            issued_at=int(time.time()),
-            meta=kwargs,
-        )
-
-
-class ExpiringRolesNotification(BaseSchedule):
-    """
-    This task does a simple check for roles that will expire in 30 days
-    and creates entries in the notification table for them.
-
-    There should be an entry in the ScheduleTask-table with name role_expiration
-    before this task is run.
-
-    Some assumptions that are made:
-
-    - The task will be run every day, it does
-    not keep track of which roles it has or has not notified, it only
-    looks at which roles will expire in exactly 30 days
-
-    - If there are roles created that expire in less than 30 days, no
-    notification is necessary
-    """
-
-    EXPIRATION_THRESHOLD_DAYS = 30
-
-    def __init__(self):
-        # Will raise exception if there is not exactly one result
-        super().__init__("role_expiration")
-
-    def _run_internal(self):
-        last_run = self.get_last_run()
-        # Only run once per day
-        if last_run is None or last_run.date() != date.today():
-            check_date = datetime.today() + timedelta(
-                days=self.EXPIRATION_THRESHOLD_DAYS
-            )
-            self.__get_roles_about_to_expire(check_date)
-
-    def __get_roles_about_to_expire(self, end_date: date):
-        roles_about_to_expire = Role.objects.filter(end_date=end_date)
-
-        for role in roles_about_to_expire:
-            meta = {"person_id": role.person.id, "type_id": role.type.id}
-            self._store_notification(
-                identifier=role.id,
-                object_type="PersonRole",
-                operation="expire_reminder",
-                **meta
-            )

greg/tests/models/test_scheduletask.py

-import pytest
-
-from greg.models import ScheduleTask
-
-
-@pytest.fixture
-def scheduletask():
-    ScheduleTask.objects.create(name="foo", last_completed="2020-10-15T23:04Z")
-    return ScheduleTask.objects.get(id=1)
-
-
-@pytest.mark.django_db
-def test_scheduletask_repr(scheduletask):
-    assert (
-        repr(scheduletask)
-        == "ScheduleTask(id=1, name='foo', last_completed=datetime.datetime(2020, 10, 15, 23, 4, tzinfo=<UTC>))"
-    )

greg/tests/test_expire_role.py

-from datetime import datetime, timedelta
-
-import pytest
-from django.db.models import Q
-from django.utils import timezone
-
-from greg.models import (
-    ScheduleTask,
-    RoleType,
-    Person,
-    OrganizationalUnit,
-    Role,
-    Notification,
-    Sponsor,
-)
-from greg.schedule import ExpiringRolesNotification
-
-
-@pytest.fixture
-def role_task():
-    ScheduleTask.objects.create(
-        name="role_expiration", last_completed=timezone.now() - timedelta(days=1)
-    )
-
-
-@pytest.fixture
-def role(
-    person: Person,
-    role_type_bar: RoleType,
-    unit_foo: OrganizationalUnit,
-    sponsor_guy: Sponsor,
-) -> Role:
-    return Role.objects.create(
-        person=person,
-        type=role_type_bar,
-        orgunit=unit_foo,
-        start_date="2020-03-05",
-        end_date=datetime.today() + timedelta(days=30),
-        contact_person_unit="Contact Person",
-        available_in_search=True,
-        sponsor=sponsor_guy,
-    )
-
-
-@pytest.mark.django_db
-def test_role_picked_up(role_task: ScheduleTask, role: Role):
-    role_notification = ExpiringRolesNotification()
-    assert len(Notification.objects.filter(~Q(operation="add"))) == 0
-    role_notification.run()
-    notification = Notification.objects.get(operation="expire_reminder")
-    assert notification.identifier == role.id
-    role_notification.run()
-    notifications = Notification.objects.filter(operation="expire_reminder")
-    assert len(notifications) == 1
-
-
-@pytest.mark.django_db
-def test_no_notification_for_role_not_about_to_expire(
-    role_task: ScheduleTask, role: Role
-):
-    role.end_date = datetime.today() + timedelta(days=31)
-    role.save()
-    role_notification = ExpiringRolesNotification()
-    assert len(Notification.objects.filter(operation="expire_reminder")) == 0
-    # Role should not be picked up since it expires in 31 days
-    role_notification.run()
-    notifications = Notification.objects.filter(operation="expire_reminder")
-    assert len(notifications) == 0