feat: Organisation reverts to free plan

api/organisations/apps.py

@@ -6,7 +6,3 @@
 
 class OrganisationsConfig(AppConfig):
     name = "organisations"
-
-    def ready(self):
-        # noinspection PyUnresolvedReferences
-        import organisations.signals  # noqa

api/organisations/chargebee/webhook_handlers.py

@@ -126,7 +126,7 @@ def process_subscription(request: Request) -> Response:
         return Response(status=status.HTTP_200_OK)
 
     if subscription["status"] in ("non_renewing", "cancelled"):
-        existing_subscription.cancel(
+        existing_subscription.prepare_for_cancel(
             datetime.fromtimestamp(subscription.get("current_term_end")).replace(
                 tzinfo=timezone.utc
             ),

api/organisations/migrations/0050_add_historical_subscription.py

@@ -0,0 +1,48 @@
+# Generated by Django 3.2.23 on 2023-12-06 17:10
+
+from django.conf import settings
+from django.db import migrations, models
+import django.db.models.deletion
+import simple_history.models
+import uuid
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+        ('organisations', '0049_subscription_billing_status'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='HistoricalSubscription',
+            fields=[
+                ('id', models.IntegerField(auto_created=True, blank=True, db_index=True, verbose_name='ID')),
+                ('deleted_at', models.DateTimeField(blank=True, db_index=True, default=None, editable=False, null=True)),
+                ('uuid', models.UUIDField(db_index=True, default=uuid.uuid4, editable=False)),
+                ('subscription_id', models.CharField(blank=True, max_length=100, null=True)),
+                ('subscription_date', models.DateTimeField(blank=True, null=True)),
+                ('plan', models.CharField(blank=True, default='free', max_length=100, null=True)),
+                ('max_seats', models.IntegerField(default=1)),
+                ('max_api_calls', models.BigIntegerField(default=50000)),
+                ('cancellation_date', models.DateTimeField(blank=True, null=True)),
+                ('customer_id', models.CharField(blank=True, max_length=100, null=True)),
+                ('billing_status', models.CharField(blank=True, choices=[('ACTIVE', 'Active'), ('DUNNING', 'Dunning')], max_length=20, null=True)),
+                ('payment_method', models.CharField(blank=True, choices=[('CHARGEBEE', 'Chargebee'), ('XERO', 'Xero'), ('AWS_MARKETPLACE', 'AWS Marketplace')], max_length=20, null=True)),
+                ('notes', models.CharField(blank=True, max_length=500, null=True)),
+                ('history_id', models.AutoField(primary_key=True, serialize=False)),
+                ('history_date', models.DateTimeField()),
+                ('history_change_reason', models.CharField(max_length=100, null=True)),
+                ('history_type', models.CharField(choices=[('+', 'Created'), ('~', 'Changed'), ('-', 'Deleted')], max_length=1)),
+                ('history_user', models.ForeignKey(null=True, on_delete=django.db.models.deletion.SET_NULL, related_name='+', to=settings.AUTH_USER_MODEL)),
+                ('organisation', models.ForeignKey(blank=True, db_constraint=False, null=True, on_delete=django.db.models.deletion.DO_NOTHING, related_name='+', to='organisations.organisation')),
+            ],
+            options={
+                'verbose_name': 'historical subscription',
+                'ordering': ('-history_date', '-history_id'),
+                'get_latest_by': 'history_date',
+            },
+            bases=(simple_history.models.HistoricalChanges, models.Model),
+        ),
+    ]

api/organisations/models.py

@@ -13,6 +13,7 @@
     LifecycleModelMixin,
     hook,
 )
+from simple_history.models import HistoricalRecords
 
 from organisations.chargebee import (
     get_customer_id_from_subscription_id,
@@ -132,7 +133,7 @@ def is_auto_seat_upgrade_available(self) -> bool:
     @hook(BEFORE_DELETE)
     def cancel_subscription(self):
         if self.has_paid_subscription():
-            self.subscription.cancel()
+            self.subscription.prepare_for_cancel()
 
     @hook(AFTER_CREATE)
     def create_subscription(self):
@@ -198,7 +199,7 @@ class Subscription(LifecycleModelMixin, SoftDeleteExportableModel):
     subscription_id = models.CharField(max_length=100, blank=True, null=True)
     subscription_date = models.DateTimeField(blank=True, null=True)
     plan = models.CharField(max_length=100, null=True, blank=True, default=FREE_PLAN_ID)
-    max_seats = models.IntegerField(default=1)
+    max_seats = models.IntegerField(default=MAX_SEATS_IN_FREE_PLAN)
     max_api_calls = models.BigIntegerField(default=MAX_API_CALLS_IN_FREE_PLAN)
     cancellation_date = models.DateTimeField(blank=True, null=True)
     customer_id = models.CharField(max_length=100, blank=True, null=True)
@@ -218,6 +219,9 @@ class Subscription(LifecycleModelMixin, SoftDeleteExportableModel):
     )
     notes = models.CharField(max_length=500, blank=True, null=True)
 
+    # Intentionally avoid the AuditLog for subscriptions.
+    history = HistoricalRecords()
+
     def update_plan(self, plan_id):
         plan_metadata = get_plan_meta_data(plan_id)
         self.cancellation_date = None
@@ -237,17 +241,64 @@ def update_mailer_lite_subscribers(self):
             mailer_lite = MailerLite()
             mailer_lite.update_organisation_users(self.organisation.id)
 
-    def cancel(self, cancellation_date=timezone.now(), update_chargebee=True):
-        self.cancellation_date = cancellation_date
+    def save_as_free_subscription(self):
+        """
+        Wipes a subscription to a normal free plan.
+
+        The only normal field that is retained is the notes field.
+        """
+        self.subscription_id = None
+        self.subscription_date = None
+        self.plan = FREE_PLAN_ID
+        self.max_seats = MAX_SEATS_IN_FREE_PLAN
+        self.max_api_calls = MAX_API_CALLS_IN_FREE_PLAN
+        self.cancellation_date = None
+        self.customer_id = None
         self.billing_status = None
+        self.payment_method = None
+
         self.save()
-        # If the date is in the future, a recurring task takes it.
-        if cancellation_date <= timezone.now():
-            self.organisation.cancel_users()
+
+        if not getattr(self.organisation, "subscription_information_cache", None):
+            return
+
+        self.organisation.subscription_information_cache.delete()
+
+    def prepare_for_cancel(
+        self, cancellation_date=timezone.now(), update_chargebee=True
+    ) -> None:
+        """
+        This method get's a subscription ready for cancelation.
+
+        If cancellation_date is in the future some aspects are
+        reserved for a task after the date has passed.
+        """
+        # Avoid circular import.
+        from organisations.tasks import send_org_subscription_cancelled_alert
 
         if self.payment_method == CHARGEBEE and update_chargebee:
             cancel_chargebee_subscription(self.subscription_id)
 
+        send_org_subscription_cancelled_alert.delay(
+            kwargs={
+                "organisation_name": self.organisation.name,
+                "formatted_cancellation_date": cancellation_date.strftime(
+                    "%Y-%m-%d %H:%M:%S"
+                ),
+            }
+        )
+
+        if cancellation_date <= timezone.now():
+            # Since the date is immediate, wipe data right away.
+            self.organisation.cancel_users()
+            self.save_as_free_subscription()
+            return
+
+        # Since the date is in the future, a task takes it.
+        self.cancellation_date = cancellation_date
+        self.billing_status = None
+        self.save()
+
     def get_portal_url(self, redirect_url):
         if not self.subscription_id:
             return None

api/organisations/tasks.py

@@ -38,6 +38,17 @@ def send_org_over_limit_alert(organisation_id):
     )
 
 
+@register_task_handler()
+def send_org_subscription_cancelled_alert(
+    organisation_name: str,
+    formatted_cancellation_date: str,
+):
+    FFAdminUser.send_alert_to_admin_users(
+        subject=f"Organisation {organisation_name} has cancelled their subscription",
+        message=f"Organisation {organisation_name} has cancelled their subscription on {formatted_cancellation_date}",
+    )
+
+
 @register_task_handler()
 def update_organisation_subscription_information_influx_cache():
     subscription_info_cache.update_caches((SubscriptionCacheEntity.INFLUX,))
@@ -61,3 +72,4 @@ def finish_subscription_cancellation():
         cancellation_date__gt=previously,
     ):
         subscription.organisation.cancel_users()
+        subscription.save_as_free_subscription()

api/tests/unit/organisations/test_unit_organisations_models.py

@@ -85,7 +85,8 @@ def test_cancel_subscription_cancels_chargebee_subscription(
         )
         # refresh subscription object
         subscription.refresh_from_db()
-        assert subscription.cancellation_date
+        # Subscription has been immediately transformed to free.
+        assert subscription.cancellation_date is None
 
 
 def test_organisation_rebuild_environment_document_on_stop_serving_flags_changed(

api/tests/unit/organisations/test_unit_organisations_tasks.py

@@ -8,10 +8,12 @@
 from organisations.models import (
     Organisation,
     OrganisationRole,
+    OrganisationSubscriptionInformationCache,
     UserOrganisation,
 )
 from organisations.subscriptions.constants import (
     FREE_PLAN_ID,
+    MAX_API_CALLS_IN_FREE_PLAN,
     MAX_SEATS_IN_FREE_PLAN,
 )
 from organisations.subscriptions.xero.metadata import XeroSubscriptionMetadata
@@ -76,7 +78,56 @@ def test_send_org_over_limit_alert_for_organisation_with_subscription(
     assert kwargs["subject"] == ALERT_EMAIL_SUBJECT
 
 
-def test_finish_subscription_cancellation(db: None):
+def test_subscription_cancellation(db: None) -> None:
+    # Given
+    organisation = Organisation.objects.create()
+    OrganisationSubscriptionInformationCache.objects.create(
+        organisation=organisation,
+    )
+    UserOrganisation.objects.create(
+        organisation=organisation,
+        user=FFAdminUser.objects.create(email=f"{uuid.uuid4()}@example.com"),
+        role=OrganisationRole.ADMIN,
+    )
+
+    assert organisation.subscription_information_cache
+    subscription = organisation.subscription
+    notes = "Notes to be kept"
+    subscription.subscription_id = "id"
+    subscription.subscription_date = timezone.now()
+    subscription.plan = "plan_code"
+    subscription.max_seats = 1_000_000
+    subscription.max_api_calls = 1_000_000
+    subscription.cancellation_date = timezone.now()
+    subscription.customer_id = "customer23"
+    subscription.billing_status = "ACTIVE"
+    subscription.payment_method = "CHARGEBEE"
+    subscription.notes = notes
+
+    subscription.save()
+
+    # When
+    finish_subscription_cancellation()
+
+    # Then
+    organisation.refresh_from_db()
+    subscription.refresh_from_db()
+    assert getattr(organisation, "subscription_information_cache", None) is None
+    assert subscription.subscription_id is None
+    assert subscription.subscription_date is None
+    assert subscription.plan == FREE_PLAN_ID
+    assert subscription.max_seats == MAX_SEATS_IN_FREE_PLAN
+    assert subscription.max_api_calls == MAX_API_CALLS_IN_FREE_PLAN
+    assert subscription.cancellation_date is None
+    assert subscription.customer_id is None
+    assert subscription.billing_status is None
+    assert subscription.payment_method is None
+    assert subscription.cancellation_date is None
+    assert subscription.notes == notes
+
+
+def test_finish_subscription_cancellation(db: None) -> None:
+    # Given
     organisation1 = Organisation.objects.create()
     organisation2 = Organisation.objects.create()
     organisation3 = Organisation.objects.create()
@@ -91,7 +142,7 @@ def test_finish_subscription_cancellation(db: None):
             role=OrganisationRole.ADMIN,
         )
     future = timezone.now() + timedelta(days=20)
-    organisation1.subscription.cancel(cancellation_date=future)
+    organisation1.subscription.prepare_for_cancel(cancellation_date=future)
 
     # Two organisations are impacted.
     for __ in range(organisation_user_count):
@@ -101,7 +152,7 @@ def test_finish_subscription_cancellation(db: None):
             role=OrganisationRole.ADMIN,
         )
 
-    organisation2.subscription.cancel(
+    organisation2.subscription.prepare_for_cancel(
         cancellation_date=timezone.now() - timedelta(hours=2)
     )
 
@@ -111,7 +162,7 @@ def test_finish_subscription_cancellation(db: None):
             user=FFAdminUser.objects.create(email=f"{uuid.uuid4()}@example.com"),
             role=OrganisationRole.ADMIN,
         )
-    organisation3.subscription.cancel(
+    organisation3.subscription.prepare_for_cancel(
         cancellation_date=timezone.now() - timedelta(hours=4)
     )
 

api/tests/unit/organisations/test_unit_organisations_views.py

@@ -1475,9 +1475,9 @@ def test_when_subscription_is_cancelled_then_remove_all_but_the_first_user(
     assert response.status_code == 200
 
     subscription.refresh_from_db()
-    assert subscription.cancellation_date == datetime.utcfromtimestamp(
-        current_term_end
-    ).replace(tzinfo=timezone.utc)
+
+    # Subscription is now a free plan.
+    assert subscription.cancellation_date is None
     organisation.refresh_from_db()
     assert organisation.num_seats == 1