text: # -*- coding: utf-8 -*-
  # Copyright 2019 The Matrix.org Foundation C.I.C.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  from synapse.rest import admin
  from synapse.rest.client.v1 import login, room
  from synapse.rest.client.v2_alpha import sync
  
  from tests.unittest import HomeserverTestCase
  
  
  class RedactionsTestCase(HomeserverTestCase):
      """Tests that various redaction events are handled correctly"""
  
      servlets = [
          admin.register_servlets,
          room.register_servlets,
          login.register_servlets,
          sync.register_servlets,
      ]
  
      def make_homeserver(self, reactor, clock):
          config = self.default_config()
  
          config["rc_message"] = {"per_second": 0.2, "burst_count": 10}
          config["rc_admin_redaction"] = {"per_second": 1, "burst_count": 100}
  
          return self.setup_test_homeserver(config=config)
  
      def prepare(self, reactor, clock, hs):
          # register a couple of users
          self.mod_user_id = self.register_user("user1", "pass")
          self.mod_access_token = self.login("user1", "pass")
          self.other_user_id = self.register_user("otheruser", "pass")
          self.other_access_token = self.login("otheruser", "pass")
  
          # Create a room
          self.room_id = self.helper.create_room_as(
              self.mod_user_id, tok=self.mod_access_token
          )
  
          # Invite the other user
          self.helper.invite(
              room=self.room_id,
              src=self.mod_user_id,
              tok=self.mod_access_token,
              targ=self.other_user_id,
          )
          # The other user joins
          self.helper.join(
              room=self.room_id, user=self.other_user_id, tok=self.other_access_token
          )
  
      def _redact_event(self, access_token, room_id, event_id, expect_code=200):
          """Helper function to send a redaction event.
  
          Returns the json body.
          """
          path = "/_matrix/client/r0/rooms/%s/redact/%s" % (room_id, event_id)
  
          request, channel = self.make_request(
              "POST", path, content={}, access_token=access_token
          )
          self.render(request)
          self.assertEqual(int(channel.result["code"]), expect_code)
          return channel.json_body
  
      def _sync_room_timeline(self, access_token, room_id):
          request, channel = self.make_request(
              "GET", "sync", access_token=self.mod_access_token
          )
          self.render(request)
          self.assertEqual(channel.result["code"], b"200")
          room_sync = channel.json_body["rooms"]["join"][room_id]
          return room_sync["timeline"]["events"]
  
      def test_redact_event_as_moderator(self):
          # as a regular user, send a message to redact
          b = self.helper.send(room_id=self.room_id, tok=self.other_access_token)
          msg_id = b["event_id"]
  
          # as the moderator, send a redaction
          b = self._redact_event(self.mod_access_token, self.room_id, msg_id)
          redaction_id = b["event_id"]
  
          # now sync
          timeline = self._sync_room_timeline(self.mod_access_token, self.room_id)
  
          # the last event should be the redaction
          self.assertEqual(timeline[-1]["event_id"], redaction_id)
          self.assertEqual(timeline[-1]["redacts"], msg_id)
  
          # and the penultimate should be the redacted original
          self.assertEqual(timeline[-2]["event_id"], msg_id)
          self.assertEqual(timeline[-2]["unsigned"]["redacted_by"], redaction_id)
          self.assertEqual(timeline[-2]["content"], {})
  
      def test_redact_event_as_normal(self):
          # as a regular user, send a message to redact
          b = self.helper.send(room_id=self.room_id, tok=self.other_access_token)
          normal_msg_id = b["event_id"]
  
          # also send one as the admin
          b = self.helper.send(room_id=self.room_id, tok=self.mod_access_token)
          admin_msg_id = b["event_id"]
  
          # as a normal, try to redact the admin's event
          self._redact_event(
              self.other_access_token, self.room_id, admin_msg_id, expect_code=403
          )
  
          # now try to redact our own event
          b = self._redact_event(self.other_access_token, self.room_id, normal_msg_id)
          redaction_id = b["event_id"]
  
          # now sync
          timeline = self._sync_room_timeline(self.other_access_token, self.room_id)
  
          # the last event should be the redaction of the normal event
          self.assertEqual(timeline[-1]["event_id"], redaction_id)
          self.assertEqual(timeline[-1]["redacts"], normal_msg_id)
  
          # the penultimate should be the unredacted one from the admin
          self.assertEqual(timeline[-2]["event_id"], admin_msg_id)
          self.assertNotIn("redacted_by", timeline[-2]["unsigned"])
          self.assertTrue(timeline[-2]["content"]["body"], {})
  
          # and the antepenultimate should be the redacted normal
          self.assertEqual(timeline[-3]["event_id"], normal_msg_id)
          self.assertEqual(timeline[-3]["unsigned"]["redacted_by"], redaction_id)
          self.assertEqual(timeline[-3]["content"], {})
  
      def test_redact_nonexistent_event(self):
          # control case: an existing event
          b = self.helper.send(room_id=self.room_id, tok=self.other_access_token)
          msg_id = b["event_id"]
          b = self._redact_event(self.other_access_token, self.room_id, msg_id)
          redaction_id = b["event_id"]
  
          # room moderators can send redactions for non-existent events
          self._redact_event(self.mod_access_token, self.room_id, "$zzz")
  
          # ... but normals cannot
          self._redact_event(
              self.other_access_token, self.room_id, "$zzz", expect_code=404
          )
  
          # when we sync, we should see only the valid redaction
          timeline = self._sync_room_timeline(self.other_access_token, self.room_id)
          self.assertEqual(timeline[-1]["event_id"], redaction_id)
          self.assertEqual(timeline[-1]["redacts"], msg_id)
  
          # and the penultimate should be the redacted original
          self.assertEqual(timeline[-2]["event_id"], msg_id)
          self.assertEqual(timeline[-2]["unsigned"]["redacted_by"], redaction_id)
          self.assertEqual(timeline[-2]["content"], {})
  
      def test_redact_create_event(self):
          # control case: an existing event
          b = self.helper.send(room_id=self.room_id, tok=self.mod_access_token)
          msg_id = b["event_id"]
          self._redact_event(self.mod_access_token, self.room_id, msg_id)
  
          # sync the room, to get the id of the create event
          timeline = self._sync_room_timeline(self.other_access_token, self.room_id)
          create_event_id = timeline[0]["event_id"]
  
          # room moderators cannot send redactions for create events
          self._redact_event(
              self.mod_access_token, self.room_id, create_event_id, expect_code=403
          )
  
          # and nor can normals
          self._redact_event(
              self.other_access_token, self.room_id, create_event_id, expect_code=403
          )
  
      def test_redact_event_as_moderator_ratelimit(self):
          """Tests that the correct ratelimiting is applied to redactions
          """
  
          message_ids = []
          # as a regular user, send messages to redact
          for _ in range(20):
              b = self.helper.send(room_id=self.room_id, tok=self.other_access_token)
              message_ids.append(b["event_id"])
              self.reactor.advance(10)  # To get around ratelimits
  
          # as the moderator, send a bunch of redactions
          for msg_id in message_ids:
              # These should all succeed, even though this would be denied by
              # the standard message ratelimiter
              self._redact_event(self.mod_access_token, self.room_id, msg_id)
  