agendas: prevent cascade deletion of custody holiday rules (#66326)

chrono/agendas/migrations/0133_auto_20220628_1600.py

@@ -0,0 +1,23 @@
+# Generated by Django 2.2.26 on 2022-06-28 14:00
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('agendas', '0132_sharedcustodysettings_holidays_calendar'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='sharedcustodyholidayrule',
+            name='holiday',
+            field=models.ForeignKey(
+                on_delete=django.db.models.deletion.PROTECT,
+                to='agendas.TimePeriodExceptionGroup',
+                verbose_name='Holiday',
+            ),
+        ),
+    ]

chrono/agendas/models.py

@@ -3369,7 +3369,7 @@ class SharedCustodyHolidayRule(models.Model):
     ]
 
     agenda = models.ForeignKey(SharedCustodyAgenda, on_delete=models.CASCADE, related_name='holiday_rules')
-    holiday = models.ForeignKey(TimePeriodExceptionGroup, verbose_name=_('Holiday'), on_delete=models.CASCADE)
+    holiday = models.ForeignKey(TimePeriodExceptionGroup, verbose_name=_('Holiday'), on_delete=models.PROTECT)
     years = models.CharField(_('Years'), choices=YEAR_CHOICES, blank=True, max_length=16)
     periodicity = models.CharField(_('Periodicity'), choices=PERIODICITY_CHOICES, blank=True, max_length=32)
     guardian = models.ForeignKey(Person, verbose_name=_('Guardian'), on_delete=models.CASCADE)

chrono/manager/views.py

@@ -31,6 +31,7 @@ from django.contrib import messages
 from django.core.exceptions import PermissionDenied
 from django.db import IntegrityError, transaction
 from django.db.models import BooleanField, Count, Max, Min, Q, Value
+from django.db.models.deletion import ProtectedError
 from django.http import Http404, HttpResponse, HttpResponseForbidden, HttpResponseRedirect
 from django.shortcuts import get_object_or_404, redirect, render
 from django.template.defaultfilters import title
@@ -3561,6 +3562,15 @@ class UnavailabilityCalendarDeleteView(DeleteView):
     def get_success_url(self):
         return reverse('chrono-manager-unavailability-calendar-list')
 
+    def delete(self, request, *args, **kwargs):
+        try:
+            return super().delete(request, *args, **kwargs)
+        except ProtectedError:
+            messages.warning(
+                request, _('This calendar cannot be deleted because it is used by shared custody agendas.')
+            )
+            return HttpResponseRedirect(self.get_object().get_absolute_url())
+
 
 unavailability_calendar_delete = UnavailabilityCalendarDeleteView.as_view()
 

tests/manager/test_shared_custody_agenda.py

@@ -290,6 +290,12 @@ def test_shared_custody_agenda_holiday_rules(app, admin_user):
     resp = app.get('/manage/shared-custody/%s/2022/12/' % agenda.pk)
     assert 'John Doe (Vacances de Noël)' in resp.text
 
+    # calendar cannot be deleted
+    resp = app.get('/manage/unavailability-calendar/%s/settings' % unavailability_calendar.pk)
+    resp = resp.click('Delete')
+    resp = resp.form.submit().follow()
+    assert 'This calendar cannot be deleted because it is used by shared custody agendas.' in resp.text
+
 
 def test_shared_custody_settings_feature_flag(app, admin_user, settings):
     settings.SHARED_CUSTODY_ENABLED = False