Show erasure status when listing users in the Admin API (#14205)

* Show erasure status when listing users in the Admin API

* Use USING when joining erased_users

* Add changelog entry

* Revert "Use USING when joining erased_users"

This reverts commit 30bd2bf106415caadcfdbdd1b234ef2b106cc394.

* Make the erased check work on postgres

* Add a testcase for showing erased user status

* Appease the style linter

* Explicitly convert `erased` to bool to make SQLite consistent with Postgres

This also adds us an easy way in to fix the other accidentally integered columns.

* Move erasure status test to UsersListTestCase

* Include user erased status when fetching user info via the admin API

* Document the erase status in user_admin_api

* Appease the linter and mypy

* Signpost comments in tests

Co-authored-by: Tadeusz Sośnierz <tadeusz@sosnierz.com>
Co-authored-by: David Robertson <david.m.robertson1@gmail.com>

5 files changed, 51 insertions, 3 deletions

diff --git a/changelog.d/14205.feature b/changelog.d/14205.feature
new file mode 100644
index 0000000000..6692063352
--- /dev/null
+++ b/changelog.d/14205.feature
@@ -0,0 +1 @@
+Show erasure status when listing users in the Admin API.
diff --git a/docs/admin_api/user_admin_api.md b/docs/admin_api/user_admin_api.md
index 3625c7b6c5..c95d6c9b05 100644
--- a/docs/admin_api/user_admin_api.md
+++ b/docs/admin_api/user_admin_api.md
@@ -37,6 +37,7 @@ It returns a JSON body like the following:
     "is_guest": 0,
     "admin": 0,
     "deactivated": 0,
+    "erased": false,
     "shadow_banned": 0,
     "creation_ts": 1560432506,
     "appservice_id": null,
@@ -167,6 +168,7 @@ A response body like the following is returned:
             "admin": 0,
             "user_type": null,
             "deactivated": 0,
+            "erased": false,
             "shadow_banned": 0,
             "displayname": "<User One>",
             "avatar_url": null,
@@ -177,6 +179,7 @@ A response body like the following is returned:
             "admin": 1,
             "user_type": null,
             "deactivated": 0,
+            "erased": false,
             "shadow_banned": 0,
             "displayname": "<User Two>",
             "avatar_url": "<avatar_url>",
@@ -247,6 +250,7 @@ The following fields are returned in the JSON response body:
   - `user_type` - string - Type of the user. Normal users are type `None`.
     This allows user type specific behaviour. There are also types `support` and `bot`. 
   - `deactivated` - bool - Status if that user has been marked as deactivated.
+  - `erased` - bool - Status if that user has been marked as erased.
   - `shadow_banned` - bool - Status if that user has been marked as shadow banned.
   - `displayname` - string - The user's display name if they have set one.
   - `avatar_url` - string -  The user's avatar URL if they have set one.
diff --git a/synapse/handlers/admin.py b/synapse/handlers/admin.py
index f2989cc4a2..5bf8e86387 100644
--- a/synapse/handlers/admin.py
+++ b/synapse/handlers/admin.py
@@ -100,6 +100,7 @@ class AdminHandler:
         user_info_dict["avatar_url"] = profile.avatar_url
         user_info_dict["threepids"] = threepids
         user_info_dict["external_ids"] = external_ids
+        user_info_dict["erased"] = await self.store.is_user_erased(user.to_string())
 
         return user_info_dict
 
diff --git a/synapse/storage/databases/main/__init__.py b/synapse/storage/databases/main/__init__.py
index a62b4abd4e..cfaedf5e0c 100644
--- a/synapse/storage/databases/main/__init__.py
+++ b/synapse/storage/databases/main/__init__.py
@@ -201,7 +201,7 @@ class DataStore(
         name: Optional[str] = None,
         guests: bool = True,
         deactivated: bool = False,
-        order_by: str = UserSortOrder.USER_ID.value,
+        order_by: str = UserSortOrder.NAME.value,
         direction: str = "f",
         approved: bool = True,
     ) -> Tuple[List[JsonDict], int]:
@@ -261,6 +261,7 @@ class DataStore(
             sql_base = f"""
                 FROM users as u
                 LEFT JOIN profiles AS p ON u.name = '@' || p.user_id || ':' || ?
+                LEFT JOIN erased_users AS eu ON u.name = eu.user_id
                 {where_clause}
                 """
             sql = "SELECT COUNT(*) as total_users " + sql_base
@@ -269,7 +270,8 @@ class DataStore(
 
             sql = f"""
                 SELECT name, user_type, is_guest, admin, deactivated, shadow_banned,
-                displayname, avatar_url, creation_ts * 1000 as creation_ts, approved
+                displayname, avatar_url, creation_ts * 1000 as creation_ts, approved,
+                eu.user_id is not null as erased
                 {sql_base}
                 ORDER BY {order_by_column} {order}, u.name ASC
                 LIMIT ? OFFSET ?
@@ -277,6 +279,13 @@ class DataStore(
             args += [limit, start]
             txn.execute(sql, args)
             users = self.db_pool.cursor_to_dict(txn)
+
+            # some of those boolean values are returned as integers when we're on SQLite
+            columns_to_boolify = ["erased"]
+            for user in users:
+                for column in columns_to_boolify:
+                    user[column] = bool(user[column])
+
             return users, count
 
         return await self.db_pool.runInteraction(
diff --git a/tests/rest/admin/test_user.py b/tests/rest/admin/test_user.py
index 4c1ce33463..63410ffdf1 100644
--- a/tests/rest/admin/test_user.py
+++ b/tests/rest/admin/test_user.py
@@ -31,7 +31,7 @@ from synapse.api.room_versions import RoomVersions
 from synapse.rest.client import devices, login, logout, profile, register, room, sync
 from synapse.rest.media.v1.filepath import MediaFilePaths
 from synapse.server import HomeServer
-from synapse.types import JsonDict, UserID
+from synapse.types import JsonDict, UserID, create_requester
 from synapse.util import Clock
 
 from tests import unittest
@@ -924,6 +924,36 @@ class UsersListTestCase(unittest.HomeserverTestCase):
         self.assertEqual(1, len(non_admin_user_ids), non_admin_user_ids)
         self.assertEqual(not_approved_user, non_admin_user_ids[0])
 
+    def test_erasure_status(self) -> None:
+        # Create a new user.
+        user_id = self.register_user("eraseme", "eraseme")
+
+        # They should appear in the list users API, marked as not erased.
+        channel = self.make_request(
+            "GET",
+            self.url + "?deactivated=true",
+            access_token=self.admin_user_tok,
+        )
+        users = {user["name"]: user for user in channel.json_body["users"]}
+        self.assertIs(users[user_id]["erased"], False)
+
+        # Deactivate that user, requesting erasure.
+        deactivate_account_handler = self.hs.get_deactivate_account_handler()
+        self.get_success(
+            deactivate_account_handler.deactivate_account(
+                user_id, erase_data=True, requester=create_requester(user_id)
+            )
+        )
+
+        # Repeat the list users query. They should now be marked as erased.
+        channel = self.make_request(
+            "GET",
+            self.url + "?deactivated=true",
+            access_token=self.admin_user_tok,
+        )
+        users = {user["name"]: user for user in channel.json_body["users"]}
+        self.assertIs(users[user_id]["erased"], True)
+
     def _order_test(
         self,
         expected_user_list: List[str],
@@ -1195,6 +1225,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
         self.assertEqual("foo@bar.com", channel.json_body["threepids"][0]["address"])
         self.assertEqual("mxc://servername/mediaid", channel.json_body["avatar_url"])
         self.assertEqual("User1", channel.json_body["displayname"])
+        self.assertFalse(channel.json_body["erased"])
 
         # Deactivate and erase user
         channel = self.make_request(
@@ -1219,6 +1250,7 @@ class DeactivateAccountTestCase(unittest.HomeserverTestCase):
         self.assertEqual(0, len(channel.json_body["threepids"]))
         self.assertIsNone(channel.json_body["avatar_url"])
         self.assertIsNone(channel.json_body["displayname"])
+        self.assertTrue(channel.json_body["erased"])
 
         self._is_erased("@user:test", True)
 
@@ -2757,6 +2789,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
         self.assertIn("avatar_url", content)
         self.assertIn("admin", content)
         self.assertIn("deactivated", content)
+        self.assertIn("erased", content)
         self.assertIn("shadow_banned", content)
         self.assertIn("creation_ts", content)
         self.assertIn("appservice_id", content)