restrictions delegations

app/applicationlayer/management/delegation/views.py

@@ -5,7 +5,7 @@ from rest_framework.response import Response
 from app.applicationlayer.utils import model_to_dict
 from rest_framework.filters import SearchFilter, OrderingFilter
 from django_filters import rest_framework as filters
-from app.entities.models import Delegation
+from app.entities.models import Delegation, Department
 from app.applicationlayer.utils import (
     CustomPagination, status_message_response, log_save
 )
@@ -67,16 +67,20 @@ class DelegationViewSet(viewsets.ModelViewSet):
         instance = self.get_object()
         new_instance = model_to_dict(instance)
 
+        exist_in_dept = instance.departments.all()
+
         # restrictions
-        if (new_instance['name'].lower() == 'head of department' or
+        if not exist_in_dept.count() > 0:
+
+            print(exist_in_dept)
+            
+            if not (new_instance['name'].lower() == 'head of department' or
                     new_instance['name'].lower() == 'sd/od' or
                     new_instance['name'].lower() == 'change control board' or
                     new_instance['name'].lower() == 'approver' or
                     new_instance['name'].lower() == 'vendor/implementor' or
                     new_instance['name'].lower() == 'requestor'):
 
-            print("hello")
-
                 self.perform_destroy(instance)
                 
                 log_save(
@@ -87,7 +91,27 @@ class DelegationViewSet(viewsets.ModelViewSet):
                     ''
                 )
 
-        return Response(status=status.HTTP_204_NO_CONTENT)
+                message = {
+                    'code': 200,
+                    'status': 'success',
+                    'message': 'Delegation Successfully deleted'
+                }
+                return Response(message, status=status.HTTP_200_OK)
+
+            else:
+                message = {
+                    'code': 400,
+                    'status': 'failed',
+                    'message': 'Default delegation cannot delete'
+                }
+                return Response(message, status=status.HTTP_400_BAD_REQUEST)
+        else:
+            message = {
+                'code': 400,
+                'status': 'failed',
+                'message': 'Cannot delete this delegation due to existing record in department'
+            }
+            return Response(message, status=status.HTTP_400_BAD_REQUEST)
 
     @transaction.atomic
     def update(self, request, *args, **kwargs):
@@ -98,6 +122,15 @@ class DelegationViewSet(viewsets.ModelViewSet):
         serializer.is_valid(raise_exception=True)
 
         old_instance = model_to_dict(instance)
+
+        # restrictions
+        if not (new_instance['name'].lower() == 'head of department' or
+                new_instance['name'].lower() == 'sd/od' or
+                new_instance['name'].lower() == 'change control board' or
+                new_instance['name'].lower() == 'approver' or
+                new_instance['name'].lower() == 'vendor/implementor' or
+                new_instance['name'].lower() == 'requestor'):
+
             self.perform_update(serializer)
             new_instance = serializer.data
 
@@ -110,3 +143,12 @@ class DelegationViewSet(viewsets.ModelViewSet):
             )
 
             return Response(serializer.data)
+        
+        else:
+            message = {
+                'code': 400,
+                'status': 'failed',
+                'message': 'Default delegation cannot edit'
+            }
+            return Response(message, status=status.HTTP_400_BAD_REQUEST)
+

app/entities/migrations/0036_auto_20191111_1549.py

+# Generated by Django 2.2 on 2019-11-11 15:49
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('entities', '0035_changerequesttemplateapprovers_is_default'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='department',
+            name='delegation',
+            field=models.ManyToManyField(related_name='departments', to='entities.Delegation'),
+        ),
+    ]

app/entities/models.py

@@ -149,7 +149,8 @@ class Department(AuditClass):
     )
     name = models.CharField(max_length=255)
     delegation = models.ManyToManyField(
-        Delegation
+        Delegation,
+        related_name='departments'
     )
 
     class Meta: