Add groups and permissions migration

opentech/users/groups.py

+GROUPS = [
+    {
+        'name': 'Applicant',
+        'permissions': [],
+    },
+    {
+        'name': 'Reviewer',
+        'permissions': [],
+    },
+    {
+        'name': 'Advisor',
+        'permissions': [],
+    },
+    {
+        'name': 'Staff',
+        'permissions': [],
+    },
+    {
+        'name': 'Manager',
+        'permissions': [
+            'add_image', 'change_image', 'delete_image',
+            'add_document', 'change_document', 'delete_document',
+            'access_admin'
+            ],
+    },
+    {
+        'name': 'Administrator',
+        'permissions': [
+            'add_image', 'change_image', 'delete_image',
+            'add_document', 'change_document', 'delete_document',
+            'add_user', 'change_user', 'delete_user',
+            'access_admin', 'change_site'
+            ],
+    }
+]

opentech/users/migrations/0002_initial_data.py

+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.7 on 2017-12-15 13:15
+from __future__ import unicode_literals
+
+from django.db import migrations
+
+from opentech.users.groups import GROUPS
+
+
+def add_groups(apps, schema_editor):
+    Group = apps.get_model('auth.Group')
+    Permission = apps.get_model('auth.Permission')
+
+    for group_data in GROUPS:
+        group, created = Group.objects.get_or_create(name=group_data['name'])
+        for permission in group_data['permissions']:
+            group.permissions.add(Permission.objects.get(codename=permission))
+    pass
+
+
+def remove_groups(apps, schema_editor):
+    Group = apps.get_model('auth.Group')
+
+    groups = [group_data['name'] for group_data in GROUPS]
+    Group.objects.filter(name__in=groups).delete()
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('users', '0001_initial'),
+        ('wagtailadmin', '0001_create_admin_access_permissions')
+    ]
+
+    operations = [
+        migrations.RunPython(add_groups, remove_groups)
+    ]