user-groups: Add delete API endpoint.

Significantly modified by tabbott to fix some bugs.

zerver/tests/test_user_groups.py

@@ -13,7 +13,8 @@ from zerver.lib.user_groups import (
     get_user_groups,
     user_groups_in_realm,
 )
-from zerver.models import UserProfile, UserGroup, get_realm, Realm
+from zerver.models import UserProfile, UserGroup, get_realm, Realm, \
+    UserGroupMembership
 
 class UserGroupTestCase(ZulipTestCase):
     def create_user_group_for_test(self, group_name,
@@ -123,3 +124,27 @@ class UserGroupAPITestCase(ZulipTestCase):
         params = {'name': 'help'}
         result = self.client_patch('/json/user_groups/1111', info=params)
         self.assert_json_error(result, "Invalid user group")
+
+    def test_user_group_delete(self):
+        # type: () -> None
+        hamlet = self.example_user('hamlet')
+        self.login(self.example_email("hamlet"))
+        params = {
+            'name': 'support',
+            'members': ujson.dumps([hamlet.id]),
+            'description': 'Support team',
+        }
+        self.client_post('/json/user_groups/create', info=params)
+        user_group = UserGroup.objects.first()
+
+        # Test success
+        self.assertEqual(UserGroup.objects.count(), 1)
+        self.assertEqual(UserGroupMembership.objects.count(), 1)
+        result = self.client_delete('/json/user_groups/{}'.format(user_group.id))
+        self.assert_json_success(result)
+        self.assertEqual(UserGroup.objects.count(), 0)
+        self.assertEqual(UserGroupMembership.objects.count(), 0)
+
+        # Test when invalid user group is supplied
+        result = self.client_delete('/json/user_groups/1111')
+        self.assert_json_error(result, "Invalid user group")

zerver/views/user_groups.py

@@ -45,3 +45,10 @@ def edit_user_group(request, user_profile,
         result['description'] = _("Description successfully updated.")
 
     return json_success(result)
+
+@has_request_variables
+def delete_user_group(request, user_profile, user_group_id=REQ(validator=check_int)):
+    # type: (HttpRequest, UserProfile, int) -> HttpResponse
+    user_group = access_user_group_by_id(user_group_id, user_profile.realm)
+    user_group.delete()
+    return json_success()

zproject/urls.py

@@ -219,7 +219,8 @@ v1_api_and_json_patterns = [
     url(r'^user_groups/create$', rest_dispatch,
         {'POST': 'zerver.views.user_groups.add_user_group'}),
     url(r'^user_groups/(?P<user_group_id>\d+)$', rest_dispatch,
-        {'PATCH': 'zerver.views.user_groups.edit_user_group'}),
+        {'PATCH': 'zerver.views.user_groups.edit_user_group',
+         'DELETE': 'zerver.views.user_groups.delete_user_group'}),
 
     # users/me -> zerver.views.user_settings
     url(r'^users/me/api_key/regenerate$', rest_dispatch,