Admin API for querying rooms where a user is a member (#8306)

Add a new admin API `GET /_synapse/admin/v1/users/<user_id>/joined_rooms` to
list all rooms where a user is a member.

tests/rest/admin/test_user.py

@@ -22,8 +22,8 @@ from mock import Mock
 
 import synapse.rest.admin
 from synapse.api.constants import UserTypes
-from synapse.api.errors import HttpResponseException, ResourceLimitError
-from synapse.rest.client.v1 import login
+from synapse.api.errors import Codes, HttpResponseException, ResourceLimitError
+from synapse.rest.client.v1 import login, room
 from synapse.rest.client.v2_alpha import sync
 
 from tests import unittest
@@ -995,3 +995,95 @@ class UserRestTestCase(unittest.HomeserverTestCase):
 
         # Ensure they're still alive
         self.assertEqual(0, channel.json_body["deactivated"])
+
+
+class UserMembershipRestTestCase(unittest.HomeserverTestCase):
+
+    servlets = [
+        synapse.rest.admin.register_servlets,
+        login.register_servlets,
+        sync.register_servlets,
+        room.register_servlets,
+    ]
+
+    def prepare(self, reactor, clock, hs):
+        self.store = hs.get_datastore()
+
+        self.admin_user = self.register_user("admin", "pass", admin=True)
+        self.admin_user_tok = self.login("admin", "pass")
+
+        self.other_user = self.register_user("user", "pass")
+        self.url = "/_synapse/admin/v1/users/%s/joined_rooms" % urllib.parse.quote(
+            self.other_user
+        )
+
+    def test_no_auth(self):
+        """
+        Try to list rooms of an user without authentication.
+        """
+        request, channel = self.make_request("GET", self.url, b"{}")
+        self.render(request)
+
+        self.assertEqual(401, int(channel.result["code"]), msg=channel.result["body"])
+        self.assertEqual(Codes.MISSING_TOKEN, channel.json_body["errcode"])
+
+    def test_requester_is_no_admin(self):
+        """
+        If the user is not a server admin, an error is returned.
+        """
+        other_user_token = self.login("user", "pass")
+
+        request, channel = self.make_request(
+            "GET", self.url, access_token=other_user_token,
+        )
+        self.render(request)
+
+        self.assertEqual(403, int(channel.result["code"]), msg=channel.result["body"])
+        self.assertEqual(Codes.FORBIDDEN, channel.json_body["errcode"])
+
+    def test_user_does_not_exist(self):
+        """
+        Tests that a lookup for a user that does not exist returns a 404
+        """
+        url = "/_synapse/admin/v1/users/@unknown_person:test/joined_rooms"
+        request, channel = self.make_request(
+            "GET", url, access_token=self.admin_user_tok,
+        )
+        self.render(request)
+
+        self.assertEqual(404, channel.code, msg=channel.json_body)
+        self.assertEqual(Codes.NOT_FOUND, channel.json_body["errcode"])
+
+    def test_user_is_not_local(self):
+        """
+        Tests that a lookup for a user that is not a local returns a 400
+        """
+        url = "/_synapse/admin/v1/users/@unknown_person:unknown_domain/joined_rooms"
+
+        request, channel = self.make_request(
+            "GET", url, access_token=self.admin_user_tok,
+        )
+        self.render(request)
+
+        self.assertEqual(400, channel.code, msg=channel.json_body)
+        self.assertEqual("Can only lookup local users", channel.json_body["error"])
+
+    def test_get_rooms(self):
+        """
+        Tests that a normal lookup for rooms is successfully
+        """
+        # Create rooms and join
+        other_user_tok = self.login("user", "pass")
+        number_rooms = 5
+        for n in range(number_rooms):
+            self.helper.create_room_as(self.other_user, tok=other_user_tok)
+
+        # Get rooms
+        request, channel = self.make_request(
+            "GET", self.url, access_token=self.admin_user_tok,
+        )
+        self.render(request)
+
+        self.assertEqual(200, channel.code, msg=channel.json_body)
+        self.assertEqual(number_rooms, channel.json_body["total"])
+        self.assertEqual(number_rooms, len(channel.json_body["joined_rooms"]))