fix(scan): set scheduler_task to null when removing periodic tasks (#8082)

api/CHANGELOG.md

@@ -13,6 +13,9 @@ All notable changes to the **Prowler API** are documented in this file.
 ### Changed
 - Reworked `GET /compliance-overviews` to return proper requirement metrics [(#7877)](https://github.com/prowler-cloud/prowler/pull/7877)
 
+### Fixed
+- Scheduled scans are no longer deleted when their daily schedule run is disabled [(#8082)](https://github.com/prowler-cloud/prowler/pull/8082)
+
 ---
 
 ## [v1.8.5] (Prowler v5.7.5)

api/src/backend/api/migrations/0031_lighthouseconfiguration.py

@@ -54,6 +54,7 @@ class Migration(migrations.Migration):
                             ("gpt-4o-mini-2024-07-18", "GPT-4o Mini v2024-07-18"),
                             ("gpt-4o-mini", "GPT-4o Mini Default"),
                         ],
+                        default="gpt-4o-2024-08-06",
                         help_text="Must be one of the supported model names",
                         max_length=50,
                     ),

api/src/backend/api/migrations/0032_scan_disable_on_cascade_periodic_tasks.py

@@ -0,0 +1,24 @@
+# Generated by Django 5.1.10 on 2025-06-23 10:04
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("api", "0031_lighthouseconfiguration"),
+        ("django_celery_beat", "0019_alter_periodictasks_options"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="scan",
+            name="scheduler_task",
+            field=models.ForeignKey(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.SET_NULL,
+                to="django_celery_beat.periodictask",
+            ),
+        ),
+    ]

api/src/backend/api/models.py

@@ -437,7 +437,7 @@ class Scan(RowLevelSecurityProtectedModel):
     completed_at = models.DateTimeField(null=True, blank=True)
     next_scan_at = models.DateTimeField(null=True, blank=True)
     scheduler_task = models.ForeignKey(
-        PeriodicTask, on_delete=models.CASCADE, null=True, blank=True
+        PeriodicTask, on_delete=models.SET_NULL, null=True, blank=True
     )
     output_location = models.CharField(blank=True, null=True, max_length=200)
 

api/src/backend/tasks/tests/test_beat.py

@@ -55,3 +55,22 @@ class TestScheduleProviderScan:
         assert "There is already a scheduled scan for this provider." in str(
             exc_info.value
         )
+
+    def test_remove_periodic_task(self, providers_fixture):
+        provider_instance = providers_fixture[0]
+
+        assert Scan.objects.count() == 0
+        with patch("tasks.tasks.perform_scheduled_scan_task.apply_async"):
+            schedule_provider_scan(provider_instance)
+
+        assert Scan.objects.count() == 1
+        scan = Scan.objects.first()
+        periodic_task = scan.scheduler_task
+        assert periodic_task is not None
+
+        periodic_task.delete()
+
+        scan.refresh_from_db()
+        # Assert the scan still exists but its scheduler_task is set to None
+        # Otherwise, Scan.DoesNotExist would be raised
+        assert Scan.objects.get(id=scan.id).scheduler_task is None