user_groups: Include settings and supergroups in error response.

The error response when a user group cannot be deactivated due
to it being used as a subgroup or for a setting includes details
about the supergroups, streams, user groups as well the settings
for which it is used.

api_docs/changelog.md

@@ -20,6 +20,13 @@ format used by the Zulip server that they are interacting with.
 
 ## Changes in Zulip 10.0
 
+**Feature level 298**
+
+* [`POST /user_groups/{user_group_id}/deactivate`](/api/deactivate-user-group):
+  Server now returns a specific error response (`"code": CANNOT_DEACTIVATE_GROUP_IN_USE`)
+  when a user group cannot be deactivated because it is in use. The
+  error response contains details about where the user group is being used.
+
 **Feature level 297**
 
 * [`GET /events`](/api/get-events), [`POST /register`](/api/register-queue):

version.py

@@ -34,7 +34,7 @@ DESKTOP_WARNING_VERSION = "5.9.3"
 # new level means in api_docs/changelog.md, as well as "**Changes**"
 # entries in the endpoint's documentation in `zulip.yaml`.
 
-API_FEATURE_LEVEL = 297  # Last bumped for saved_snippets
+API_FEATURE_LEVEL = 298  # Last bumped for CANNOT_DEACTIVATE_GROUP_IN_USE error.
 
 # Bump the minor PROVISION_VERSION to indicate that folks should provision
 # only when going from an old version of the code to a newer version. Bump

zerver/lib/exceptions.py

@@ -54,6 +54,7 @@ class ErrorCode(Enum):
     PUSH_NOTIFICATIONS_DISALLOWED = auto()
     EXPECTATION_MISMATCH = auto()
     SYSTEM_GROUP_REQUIRED = auto()
+    CANNOT_DEACTIVATE_GROUP_IN_USE = auto()
 
 
 class JsonableError(Exception):
@@ -715,3 +716,19 @@ class IncompatibleParameterValuesError(JsonableError):
     @override
     def msg_format() -> str:
         return _("Incompatible values for '{first_parameter}' and '{second_parameter}'.")
+
+
+class CannotDeactivateGroupInUseError(JsonableError):
+    code = ErrorCode.CANNOT_DEACTIVATE_GROUP_IN_USE
+    data_fields = ["objections"]
+
+    def __init__(
+        self,
+        objections: list[dict[str, Any]],
+    ) -> None:
+        self.objections = objections
+
+    @staticmethod
+    @override
+    def msg_format() -> str:
+        return _("Cannot deactivate user group in use.")

zerver/lib/user_groups.py

@@ -2,7 +2,7 @@ from collections import defaultdict
 from collections.abc import Collection, Iterable, Iterator, Mapping
 from contextlib import contextmanager
 from dataclasses import asdict, dataclass
-from typing import TypedDict
+from typing import Any, TypedDict
 
 from django.conf import settings
 from django.db import connection, transaction
@@ -13,6 +13,7 @@ from django_cte import With
 from psycopg2.sql import SQL, Literal
 
 from zerver.lib.exceptions import (
+    CannotDeactivateGroupInUseError,
     JsonableError,
     PreviousSettingValueMismatchedError,
     SystemGroupRequiredError,
@@ -198,14 +199,14 @@ def access_user_group_for_deactivation(
         user_group_id, user_profile, permission_setting="can_manage_group"
     )
 
-    if (
+    objections: list[dict[str, Any]] = []
+    supergroup_ids = (
         user_group.direct_supergroups.exclude(named_user_group=None)
         .filter(named_user_group__deactivated=False)
-        .exists()
-    ):
-        raise JsonableError(
-            _("You cannot deactivate a user group that is subgroup of any user group.")
-        )
+        .values_list("id", flat=True)
+    )
+    if supergroup_ids:
+        objections.append(dict(type="subgroup", supergroup_ids=list(supergroup_ids)))
 
     anonymous_supergroup_ids = user_group.direct_supergroups.filter(
         named_user_group=None
@@ -214,10 +215,10 @@ def access_user_group_for_deactivation(
     # We check both the cases - whether the group is being directly used
     # as the value of a setting or as a subgroup of an anonymous group
     # used for a setting.
-    setting_group_ids_using_deactivating_user_group = [
-        *list(anonymous_supergroup_ids),
+    setting_group_ids_using_deactivating_user_group = {
+        *set(anonymous_supergroup_ids),
         user_group.id,
-    ]
+    }
 
     stream_setting_query = Q()
     for setting_name in Stream.stream_permission_group_settings:
@@ -225,12 +226,19 @@ def access_user_group_for_deactivation(
             **{f"{setting_name}__in": setting_group_ids_using_deactivating_user_group}
         )
 
-    if (
-        Stream.objects.filter(realm_id=user_group.realm_id, deactivated=False)
-        .filter(stream_setting_query)
-        .exists()
+    for stream in Stream.objects.filter(realm_id=user_group.realm_id, deactivated=False).filter(
+        stream_setting_query
     ):
-        raise JsonableError(_("You cannot deactivate a user group which is used for setting."))
+        objection_settings = [
+            setting_name
+            for setting_name in Stream.stream_permission_group_settings
+            if getattr(stream, setting_name + "_id")
+            in setting_group_ids_using_deactivating_user_group
+        ]
+        if len(objection_settings) > 0:
+            objections.append(
+                dict(type="channel", channel_id=stream.id, settings=objection_settings)
+            )
 
     group_setting_query = Q()
     for setting_name in NamedUserGroup.GROUP_PERMISSION_SETTINGS:
@@ -238,22 +246,33 @@ def access_user_group_for_deactivation(
             **{f"{setting_name}__in": setting_group_ids_using_deactivating_user_group}
         )
 
-    if (
-        NamedUserGroup.objects.filter(realm_id=user_group.realm_id, deactivated=False)
-        .filter(group_setting_query)
-        .exists()
-    ):
-        raise JsonableError(_("You cannot deactivate a user group which is used for setting."))
+    for group in NamedUserGroup.objects.filter(
+        realm_id=user_group.realm_id, deactivated=False
+    ).filter(group_setting_query):
+        objection_settings = []
+        for setting_name in NamedUserGroup.GROUP_PERMISSION_SETTINGS:
+            if (
+                getattr(group, setting_name + "_id")
+                in setting_group_ids_using_deactivating_user_group
+            ):
+                objection_settings.append(setting_name)
 
-    realm_setting_query = Q()
+        if len(objection_settings) > 0:
+            objections.append(
+                dict(type="user_group", group_id=group.id, settings=objection_settings)
+            )
+
+    objection_settings = []
+    realm = user_group.realm
     for setting_name in Realm.REALM_PERMISSION_GROUP_SETTINGS:
-        realm_setting_query |= Q(
-            **{f"{setting_name}__in": setting_group_ids_using_deactivating_user_group}
-        )
+        if getattr(realm, setting_name + "_id") in setting_group_ids_using_deactivating_user_group:
+            objection_settings.append(setting_name)
 
-    if Realm.objects.filter(id=user_group.realm_id).filter(realm_setting_query).exists():
-        raise JsonableError(_("You cannot deactivate a user group which is used for setting."))
+    if objection_settings:
+        objections.append(dict(type="realm", settings=objection_settings))
 
+    if len(objections) > 0:
+        raise CannotDeactivateGroupInUseError(objections)
     return user_group
 
 

zerver/openapi/zulip.yaml

@@ -20651,6 +20651,44 @@ paths:
       responses:
         "200":
           $ref: "#/components/responses/SimpleSuccess"
+        "400":
+          description: Bad request.
+          content:
+            application/json:
+              schema:
+                oneOf:
+                  - allOf:
+                      - $ref: "#/components/schemas/CodedError"
+                      - example:
+                          {
+                            "code": "BAD_REQUEST",
+                            "msg": "Invalid user group",
+                            "result": "error",
+                          }
+                        description: |
+                          An example JSON response when the user group ID is invalid.
+                  - allOf:
+                      - $ref: "#/components/schemas/CodedError"
+                      - example:
+                          {
+                            "code": "CANNOT_DEACTIVATE_GROUP_IN_USE",
+                            "msg": "Cannot deactivate user group in use.",
+                            "objections":
+                              [
+                                {
+                                  "type": "realm",
+                                  "settings":
+                                    ["can_create_public_channel_group"],
+                                },
+                              ],
+                            "result": "error",
+                          }
+                        description: |
+                          An example JSON response when the user group being deactivated
+                          is used for a setting or as a subgroup.
+
+                          **Changes**: New in Zulip 10.0 (feature level 298). Previously,
+                          this error returned the `"BAD_REQUEST"` code.
   /real-time:
     # This entry is a hack; it exists to give us a place to put the text
     # documenting the parameters for call_on_each_event and friends.

zerver/tests/test_user_groups.py

@@ -1355,8 +1355,10 @@ class UserGroupAPITestCase(UserGroupTestCase):
         )
         # Check that group that is subgroup of another group cannot be deactivated.
         result = self.client_post(f"/json/user_groups/{leadership_group.id}/deactivate")
-        self.assert_json_error(
-            result, "You cannot deactivate a user group that is subgroup of any user group."
+        self.assert_json_error(result, "Cannot deactivate user group in use.")
+        data = orjson.loads(result.content)
+        self.assertEqual(
+            data["objections"], [{"type": "subgroup", "supergroup_ids": [support_group.id]}]
         )
 
         # If the supergroup is itself deactivated, then subgroup can be deactivated.
@@ -1393,18 +1395,18 @@ class UserGroupAPITestCase(UserGroupTestCase):
             )
 
             result = self.client_post(f"/json/user_groups/{support_group.id}/deactivate")
-            self.assert_json_error(
-                result, "You cannot deactivate a user group which is used for setting."
-            )
+            self.assert_json_error(result, "Cannot deactivate user group in use.")
+            data = orjson.loads(result.content)
+            self.assertEqual(data["objections"], [{"type": "realm", "settings": [setting_name]}])
 
             do_change_realm_permission_group_setting(
                 realm, setting_name, support_group, acting_user=None
             )
 
             result = self.client_post(f"/json/user_groups/{support_group.id}/deactivate")
-            self.assert_json_error(
-                result, "You cannot deactivate a user group which is used for setting."
-            )
+            self.assert_json_error(result, "Cannot deactivate user group in use.")
+            data = orjson.loads(result.content)
+            self.assertEqual(data["objections"], [{"type": "realm", "settings": [setting_name]}])
 
             # Reset the realm setting to one of the system group so this setting
             # does not interfere when testing for another setting.
@@ -1419,8 +1421,11 @@ class UserGroupAPITestCase(UserGroupTestCase):
             )
 
             result = self.client_post(f"/json/user_groups/{support_group.id}/deactivate")
-            self.assert_json_error(
-                result, "You cannot deactivate a user group which is used for setting."
+            self.assert_json_error(result, "Cannot deactivate user group in use.")
+            data = orjson.loads(result.content)
+            self.assertEqual(
+                data["objections"],
+                [{"type": "channel", "channel_id": stream.id, "settings": [setting_name]}],
             )
 
             # Test the group can be deactivated, if the stream which uses
@@ -1444,8 +1449,11 @@ class UserGroupAPITestCase(UserGroupTestCase):
             )
 
             result = self.client_post(f"/json/user_groups/{support_group.id}/deactivate")
-            self.assert_json_error(
-                result, "You cannot deactivate a user group which is used for setting."
+            self.assert_json_error(result, "Cannot deactivate user group in use.")
+            data = orjson.loads(result.content)
+            self.assertEqual(
+                data["objections"],
+                [{"type": "channel", "channel_id": stream.id, "settings": [setting_name]}],
             )
 
             # Test the group can be deactivated, if the stream which uses
@@ -1473,8 +1481,17 @@ class UserGroupAPITestCase(UserGroupTestCase):
             )
 
             result = self.client_post(f"/json/user_groups/{support_group.id}/deactivate")
-            self.assert_json_error(
-                result, "You cannot deactivate a user group which is used for setting."
+            self.assert_json_error(result, "Cannot deactivate user group in use.")
+            data = orjson.loads(result.content)
+            self.assertEqual(
+                data["objections"],
+                [
+                    {
+                        "type": "user_group",
+                        "group_id": leadership_group.id,
+                        "settings": [setting_name],
+                    }
+                ],
             )
 
             # Test the group can be deactivated, if the user group which uses
@@ -1499,8 +1516,17 @@ class UserGroupAPITestCase(UserGroupTestCase):
             )
 
             result = self.client_post(f"/json/user_groups/{support_group.id}/deactivate")
-            self.assert_json_error(
-                result, "You cannot deactivate a user group which is used for setting."
+            self.assert_json_error(result, "Cannot deactivate user group in use.")
+            data = orjson.loads(result.content)
+            self.assertEqual(
+                data["objections"],
+                [
+                    {
+                        "type": "user_group",
+                        "group_id": leadership_group.id,
+                        "settings": [setting_name],
+                    }
+                ],
             )
 
             # Test the group can be deactivated, if the user group which uses