Permissions script and updated readme

.gitignore

@@ -1,3 +1,4 @@
+.idea/workspace.xml
 etc/
 
 # Swap

README.md

@@ -36,6 +36,12 @@
 
     # check for any obvious issues
     python manage.py check
+
+    # set group permissions (add and change for ALL apps)
+    python manage.py set_group_permissions --group-name='foo'
+
+    # set group permissions (add and change for specified apps)
+    python manage.py set_group_permissions --group-name='foo' --app-list='foo,bar,foobar'
 
 
 ### Production setup

ambition/management/commands/set_group_permissions.py

@@ -0,0 +1,34 @@
+import os
+
+from django.apps import apps as django_apps
+from django.core.management.base import BaseCommand, CommandError
+from django.apps import apps
+from ...permissions import Permissions
+from django.conf import settings
+
+
+class Command(BaseCommand):
+
+    help = 'Set permissions for group'
+
+    def add_arguments(self, parser):
+        parser.add_argument(
+            '--group-name',
+            dest='group_name',
+            default=None,
+            help=('group name in which you want to set app permissions',
+                  'for'),
+        )
+
+        parser.add_argument(
+            '--app-list',
+            dest='list_of_apps',
+            default=None,
+            help=('group name in which you want to set app permissions',
+                  'for'),
+        )
+
+    def handle(self, *args, **options):
+        app_list = options['list_of_apps'].split(',') if options['list_of_apps'] else None
+        group_name = options['group_name']
+        Permissions(group_name, app_list)

ambition/permissions.py

@@ -0,0 +1,51 @@
+from django.db.models import Q
+from django.apps import apps
+from django.contrib.auth.models import Group, Permission
+
+
+class PermissionsInvalidAppError(Exception):
+    pass
+
+
+class Permissions:
+
+    def __init__(self, group_name=None, list_of_apps=None):
+        new_group, created = Group.objects.get_or_create(name=group_name)
+
+        """ Provided a list of apps is given """
+        if list_of_apps:
+            for app in list_of_apps:
+                self.add_permissions_for_app(group_name=new_group, app=app)
+        else:
+            self.add_for_all_apps(group_name=new_group)
+
+    def add_permissions_for_app(self, group_name=None, app=None):
+        """Given a group name and a specific app,
+            input add & change permissions for the app."""
+
+        try:
+            app_models = apps.get_app_config(app).get_models()
+
+        except LookupError:
+            raise LookupError(f'Got invalid app name {app}')
+
+        else:
+            for model in app_models:
+                permissions = Permission.objects.filter(
+                    Q(codename__contains=model._meta.model_name),
+                    Q(codename__startswith='add_') |
+                    Q(codename__startswith='change_'))
+                for permission in permissions:
+                    group_name.permissions.add(permission)
+            group_name.save()
+
+
+    def add_for_all_apps(self, group_name=None):
+        """Get list of ALL app permissions with add and change.
+            Will be called if list of apps is not specified"""
+        permissions = Permission.objects.filter(
+            Q(codename__startswith='add_') |
+            Q(codename__startswith='change_'))
+        for permission in permissions:
+            group_name.permissions.add(permission)
+        group_name.save()