879 lines
		
	
	
		
			34 KiB
		
	
	
	
		
			Python
		
	
	
			
		
		
	
	
			879 lines
		
	
	
		
			34 KiB
		
	
	
	
		
			Python
		
	
	
# Copyright 2017 New Vector Ltd
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# Copyright 2019 The Matrix.org Foundation C.I.C.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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#     http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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import inspect
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import logging
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from typing import (
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    TYPE_CHECKING,
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    Any,
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    Awaitable,
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    Callable,
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    Collection,
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    List,
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    Optional,
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    Tuple,
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    Union,
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)
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# `Literal` appears with Python 3.8.
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from typing_extensions import Literal
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import synapse
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from synapse.api.errors import Codes
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from synapse.logging.opentracing import trace
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from synapse.media._base import FileInfo
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from synapse.media.media_storage import ReadableFileWrapper
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from synapse.spam_checker_api import RegistrationBehaviour
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from synapse.types import JsonDict, RoomAlias, UserProfile
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from synapse.util.async_helpers import delay_cancellation, maybe_awaitable
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from synapse.util.metrics import Measure
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if TYPE_CHECKING:
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    import synapse.events
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    import synapse.server
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logger = logging.getLogger(__name__)
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CHECK_EVENT_FOR_SPAM_CALLBACK = Callable[
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    ["synapse.events.EventBase"],
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    Awaitable[
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        Union[
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            str,
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            Codes,
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            # Highly experimental, not officially part of the spamchecker API, may
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            # disappear without warning depending on the results of ongoing
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            # experiments.
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            # Use this to return additional information as part of an error.
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            Tuple[Codes, JsonDict],
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            # Deprecated
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            bool,
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        ]
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    ],
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]
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SHOULD_DROP_FEDERATED_EVENT_CALLBACK = Callable[
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    ["synapse.events.EventBase"],
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    Awaitable[Union[bool, str]],
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]
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USER_MAY_JOIN_ROOM_CALLBACK = Callable[
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    [str, str, bool],
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    Awaitable[
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        Union[
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            Literal["NOT_SPAM"],
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            Codes,
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            # Highly experimental, not officially part of the spamchecker API, may
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            # disappear without warning depending on the results of ongoing
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            # experiments.
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            # Use this to return additional information as part of an error.
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            Tuple[Codes, JsonDict],
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            # Deprecated
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            bool,
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        ]
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    ],
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]
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USER_MAY_INVITE_CALLBACK = Callable[
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    [str, str, str],
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    Awaitable[
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        Union[
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            Literal["NOT_SPAM"],
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            Codes,
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            # Highly experimental, not officially part of the spamchecker API, may
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            # disappear without warning depending on the results of ongoing
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            # experiments.
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            # Use this to return additional information as part of an error.
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            Tuple[Codes, JsonDict],
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            # Deprecated
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            bool,
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        ]
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    ],
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]
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USER_MAY_SEND_3PID_INVITE_CALLBACK = Callable[
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    [str, str, str, str],
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    Awaitable[
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        Union[
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            Literal["NOT_SPAM"],
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            Codes,
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            # Highly experimental, not officially part of the spamchecker API, may
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            # disappear without warning depending on the results of ongoing
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            # experiments.
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            # Use this to return additional information as part of an error.
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            Tuple[Codes, JsonDict],
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            # Deprecated
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            bool,
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        ]
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    ],
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]
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USER_MAY_CREATE_ROOM_CALLBACK = Callable[
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    [str],
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    Awaitable[
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        Union[
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            Literal["NOT_SPAM"],
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            Codes,
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            # Highly experimental, not officially part of the spamchecker API, may
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            # disappear without warning depending on the results of ongoing
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            # experiments.
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            # Use this to return additional information as part of an error.
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            Tuple[Codes, JsonDict],
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            # Deprecated
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            bool,
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        ]
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    ],
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]
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USER_MAY_CREATE_ROOM_ALIAS_CALLBACK = Callable[
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    [str, RoomAlias],
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    Awaitable[
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        Union[
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            Literal["NOT_SPAM"],
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            Codes,
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            # Highly experimental, not officially part of the spamchecker API, may
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            # disappear without warning depending on the results of ongoing
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            # experiments.
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            # Use this to return additional information as part of an error.
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            Tuple[Codes, JsonDict],
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            # Deprecated
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            bool,
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        ]
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    ],
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]
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USER_MAY_PUBLISH_ROOM_CALLBACK = Callable[
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    [str, str],
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    Awaitable[
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        Union[
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            Literal["NOT_SPAM"],
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            Codes,
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            # Highly experimental, not officially part of the spamchecker API, may
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            # disappear without warning depending on the results of ongoing
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            # experiments.
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            # Use this to return additional information as part of an error.
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            Tuple[Codes, JsonDict],
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            # Deprecated
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            bool,
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        ]
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    ],
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]
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CHECK_USERNAME_FOR_SPAM_CALLBACK = Callable[[UserProfile], Awaitable[bool]]
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LEGACY_CHECK_REGISTRATION_FOR_SPAM_CALLBACK = Callable[
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    [
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        Optional[dict],
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        Optional[str],
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        Collection[Tuple[str, str]],
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    ],
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    Awaitable[RegistrationBehaviour],
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]
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CHECK_REGISTRATION_FOR_SPAM_CALLBACK = Callable[
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    [
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        Optional[dict],
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        Optional[str],
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        Collection[Tuple[str, str]],
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        Optional[str],
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    ],
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    Awaitable[RegistrationBehaviour],
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]
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CHECK_MEDIA_FILE_FOR_SPAM_CALLBACK = Callable[
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    [ReadableFileWrapper, FileInfo],
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    Awaitable[
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        Union[
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            Literal["NOT_SPAM"],
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            Codes,
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            # Highly experimental, not officially part of the spamchecker API, may
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            # disappear without warning depending on the results of ongoing
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            # experiments.
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            # Use this to return additional information as part of an error.
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            Tuple[Codes, JsonDict],
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            # Deprecated
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            bool,
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        ]
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    ],
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]
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CHECK_LOGIN_FOR_SPAM_CALLBACK = Callable[
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    [
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        str,
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        Optional[str],
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        Optional[str],
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        Collection[Tuple[Optional[str], str]],
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        Optional[str],
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    ],
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    Awaitable[
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        Union[
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            Literal["NOT_SPAM"],
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            Codes,
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            # Highly experimental, not officially part of the spamchecker API, may
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            # disappear without warning depending on the results of ongoing
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            # experiments.
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            # Use this to return additional information as part of an error.
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            Tuple[Codes, JsonDict],
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        ]
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    ],
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]
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def load_legacy_spam_checkers(hs: "synapse.server.HomeServer") -> None:
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    """Wrapper that loads spam checkers configured using the old configuration, and
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    registers the spam checker hooks they implement.
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    """
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    spam_checkers: List[Any] = []
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    api = hs.get_module_api()
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    for module, config in hs.config.spamchecker.spam_checkers:
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        # Older spam checkers don't accept the `api` argument, so we
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        # try and detect support.
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        spam_args = inspect.getfullargspec(module)
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        if "api" in spam_args.args:
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            spam_checkers.append(module(config=config, api=api))
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        else:
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            spam_checkers.append(module(config=config))
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    # The known spam checker hooks. If a spam checker module implements a method
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    # which name appears in this set, we'll want to register it.
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    spam_checker_methods = {
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        "check_event_for_spam",
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        "user_may_invite",
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        "user_may_create_room",
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        "user_may_create_room_alias",
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        "user_may_publish_room",
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        "check_username_for_spam",
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        "check_registration_for_spam",
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        "check_media_file_for_spam",
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    }
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    for spam_checker in spam_checkers:
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        # Methods on legacy spam checkers might not be async, so we wrap them around a
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        # wrapper that will call maybe_awaitable on the result.
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        def async_wrapper(f: Optional[Callable]) -> Optional[Callable[..., Awaitable]]:
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            # f might be None if the callback isn't implemented by the module. In this
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            # case we don't want to register a callback at all so we return None.
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            if f is None:
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                return None
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            wrapped_func = f
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            if f.__name__ == "check_registration_for_spam":
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                checker_args = inspect.signature(f)
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                if len(checker_args.parameters) == 3:
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                    # Backwards compatibility; some modules might implement a hook that
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                    # doesn't expect a 4th argument. In this case, wrap it in a function
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                    # that gives it only 3 arguments and drops the auth_provider_id on
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                    # the floor.
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                    def wrapper(
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                        email_threepid: Optional[dict],
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                        username: Optional[str],
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                        request_info: Collection[Tuple[str, str]],
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                        auth_provider_id: Optional[str],
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                    ) -> Union[Awaitable[RegistrationBehaviour], RegistrationBehaviour]:
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                        # Assertion required because mypy can't prove we won't
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                        # change `f` back to `None`. See
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                        # https://mypy.readthedocs.io/en/latest/common_issues.html#narrowing-and-inner-functions
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                        assert f is not None
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                        return f(
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                            email_threepid,
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                            username,
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                            request_info,
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                        )
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                    wrapped_func = wrapper
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                elif len(checker_args.parameters) != 4:
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                    raise RuntimeError(
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                        "Bad signature for callback check_registration_for_spam",
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                    )
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            def run(*args: Any, **kwargs: Any) -> Awaitable:
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                # Assertion required because mypy can't prove we won't change `f`
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                # back to `None`. See
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                # https://mypy.readthedocs.io/en/latest/common_issues.html#narrowing-and-inner-functions
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                assert wrapped_func is not None
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                return maybe_awaitable(wrapped_func(*args, **kwargs))
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            return run
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        # Register the hooks through the module API.
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        hooks = {
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            hook: async_wrapper(getattr(spam_checker, hook, None))
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            for hook in spam_checker_methods
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        }
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        api.register_spam_checker_callbacks(**hooks)
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class SpamCheckerModuleApiCallbacks:
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    NOT_SPAM: Literal["NOT_SPAM"] = "NOT_SPAM"
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    def __init__(self, hs: "synapse.server.HomeServer") -> None:
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        self.clock = hs.get_clock()
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        self._check_event_for_spam_callbacks: List[CHECK_EVENT_FOR_SPAM_CALLBACK] = []
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        self._should_drop_federated_event_callbacks: List[
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            SHOULD_DROP_FEDERATED_EVENT_CALLBACK
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        ] = []
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        self._user_may_join_room_callbacks: List[USER_MAY_JOIN_ROOM_CALLBACK] = []
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        self._user_may_invite_callbacks: List[USER_MAY_INVITE_CALLBACK] = []
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        self._user_may_send_3pid_invite_callbacks: List[
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            USER_MAY_SEND_3PID_INVITE_CALLBACK
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        ] = []
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        self._user_may_create_room_callbacks: List[USER_MAY_CREATE_ROOM_CALLBACK] = []
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        self._user_may_create_room_alias_callbacks: List[
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            USER_MAY_CREATE_ROOM_ALIAS_CALLBACK
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        ] = []
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        self._user_may_publish_room_callbacks: List[USER_MAY_PUBLISH_ROOM_CALLBACK] = []
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        self._check_username_for_spam_callbacks: List[
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            CHECK_USERNAME_FOR_SPAM_CALLBACK
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        ] = []
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        self._check_registration_for_spam_callbacks: List[
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            CHECK_REGISTRATION_FOR_SPAM_CALLBACK
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        ] = []
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        self._check_media_file_for_spam_callbacks: List[
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            CHECK_MEDIA_FILE_FOR_SPAM_CALLBACK
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        ] = []
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        self._check_login_for_spam_callbacks: List[CHECK_LOGIN_FOR_SPAM_CALLBACK] = []
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    def register_callbacks(
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        self,
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        check_event_for_spam: Optional[CHECK_EVENT_FOR_SPAM_CALLBACK] = None,
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        should_drop_federated_event: Optional[
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            SHOULD_DROP_FEDERATED_EVENT_CALLBACK
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        ] = None,
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        user_may_join_room: Optional[USER_MAY_JOIN_ROOM_CALLBACK] = None,
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        user_may_invite: Optional[USER_MAY_INVITE_CALLBACK] = None,
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        user_may_send_3pid_invite: Optional[USER_MAY_SEND_3PID_INVITE_CALLBACK] = None,
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        user_may_create_room: Optional[USER_MAY_CREATE_ROOM_CALLBACK] = None,
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        user_may_create_room_alias: Optional[
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            USER_MAY_CREATE_ROOM_ALIAS_CALLBACK
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        ] = None,
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        user_may_publish_room: Optional[USER_MAY_PUBLISH_ROOM_CALLBACK] = None,
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        check_username_for_spam: Optional[CHECK_USERNAME_FOR_SPAM_CALLBACK] = None,
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        check_registration_for_spam: Optional[
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            CHECK_REGISTRATION_FOR_SPAM_CALLBACK
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        ] = None,
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        check_media_file_for_spam: Optional[CHECK_MEDIA_FILE_FOR_SPAM_CALLBACK] = None,
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        check_login_for_spam: Optional[CHECK_LOGIN_FOR_SPAM_CALLBACK] = None,
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    ) -> None:
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        """Register callbacks from module for each hook."""
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        if check_event_for_spam is not None:
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            self._check_event_for_spam_callbacks.append(check_event_for_spam)
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        if should_drop_federated_event is not None:
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            self._should_drop_federated_event_callbacks.append(
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                should_drop_federated_event
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            )
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        if user_may_join_room is not None:
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            self._user_may_join_room_callbacks.append(user_may_join_room)
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        if user_may_invite is not None:
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            self._user_may_invite_callbacks.append(user_may_invite)
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        if user_may_send_3pid_invite is not None:
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            self._user_may_send_3pid_invite_callbacks.append(
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                user_may_send_3pid_invite,
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            )
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        if user_may_create_room is not None:
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            self._user_may_create_room_callbacks.append(user_may_create_room)
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        if user_may_create_room_alias is not None:
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            self._user_may_create_room_alias_callbacks.append(
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                user_may_create_room_alias,
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            )
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        if user_may_publish_room is not None:
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            self._user_may_publish_room_callbacks.append(user_may_publish_room)
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        if check_username_for_spam is not None:
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            self._check_username_for_spam_callbacks.append(check_username_for_spam)
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        if check_registration_for_spam is not None:
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            self._check_registration_for_spam_callbacks.append(
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                check_registration_for_spam,
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            )
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        if check_media_file_for_spam is not None:
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            self._check_media_file_for_spam_callbacks.append(check_media_file_for_spam)
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        if check_login_for_spam is not None:
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            self._check_login_for_spam_callbacks.append(check_login_for_spam)
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    @trace
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    async def check_event_for_spam(
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        self, event: "synapse.events.EventBase"
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    ) -> Union[Tuple[Codes, JsonDict], str]:
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        """Checks if a given event is considered "spammy" by this server.
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        If the server considers an event spammy, then it will be rejected if
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        sent by a local user. If it is sent by a user on another server, the
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        event is soft-failed.
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        Args:
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            event: the event to be checked
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        Returns:
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            - `NOT_SPAM` if the event is considered good (non-spammy) and should be let
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                through. Other spamcheck filters may still reject it.
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            - A `Code` if the event is considered spammy and is rejected with a specific
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                error message/code.
 | 
						|
            - A string that isn't `NOT_SPAM` if the event is considered spammy and the
 | 
						|
                string should be used as the client-facing error message. This usage is
 | 
						|
                generally discouraged as it doesn't support internationalization.
 | 
						|
        """
 | 
						|
        for callback in self._check_event_for_spam_callbacks:
 | 
						|
            with Measure(self.clock, f"{callback.__module__}.{callback.__qualname__}"):
 | 
						|
                res = await delay_cancellation(callback(event))
 | 
						|
                if res is False or res == self.NOT_SPAM:
 | 
						|
                    # This spam-checker accepts the event.
 | 
						|
                    # Other spam-checkers may reject it, though.
 | 
						|
                    continue
 | 
						|
                elif res is True:
 | 
						|
                    # This spam-checker rejects the event with deprecated
 | 
						|
                    # return value `True`
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
                elif (
 | 
						|
                    isinstance(res, tuple)
 | 
						|
                    and len(res) == 2
 | 
						|
                    and isinstance(res[0], synapse.api.errors.Codes)
 | 
						|
                    and isinstance(res[1], dict)
 | 
						|
                ):
 | 
						|
                    return res
 | 
						|
                elif isinstance(res, synapse.api.errors.Codes):
 | 
						|
                    return res, {}
 | 
						|
                elif not isinstance(res, str):
 | 
						|
                    # mypy complains that we can't reach this code because of the
 | 
						|
                    # return type in CHECK_EVENT_FOR_SPAM_CALLBACK, but we don't know
 | 
						|
                    # for sure that the module actually returns it.
 | 
						|
                    logger.warning(
 | 
						|
                        "Module returned invalid value, rejecting message as spam"
 | 
						|
                    )
 | 
						|
                    res = "This message has been rejected as probable spam"
 | 
						|
                else:
 | 
						|
                    # The module rejected the event either with a `Codes`
 | 
						|
                    # or some other `str`. In either case, we stop here.
 | 
						|
                    pass
 | 
						|
 | 
						|
                return res
 | 
						|
 | 
						|
        # No spam-checker has rejected the event, let it pass.
 | 
						|
        return self.NOT_SPAM
 | 
						|
 | 
						|
    async def should_drop_federated_event(
 | 
						|
        self, event: "synapse.events.EventBase"
 | 
						|
    ) -> Union[bool, str]:
 | 
						|
        """Checks if a given federated event is considered "spammy" by this
 | 
						|
        server.
 | 
						|
 | 
						|
        If the server considers an event spammy, it will be silently dropped,
 | 
						|
        and in doing so will split-brain our view of the room's DAG.
 | 
						|
 | 
						|
        Args:
 | 
						|
            event: the event to be checked
 | 
						|
 | 
						|
        Returns:
 | 
						|
            True if the event should be silently dropped
 | 
						|
        """
 | 
						|
        for callback in self._should_drop_federated_event_callbacks:
 | 
						|
            with Measure(self.clock, f"{callback.__module__}.{callback.__qualname__}"):
 | 
						|
                res: Union[bool, str] = await delay_cancellation(callback(event))
 | 
						|
            if res:
 | 
						|
                return res
 | 
						|
 | 
						|
        return False
 | 
						|
 | 
						|
    async def user_may_join_room(
 | 
						|
        self, user_id: str, room_id: str, is_invited: bool
 | 
						|
    ) -> Union[Tuple[Codes, JsonDict], Literal["NOT_SPAM"]]:
 | 
						|
        """Checks if a given users is allowed to join a room.
 | 
						|
        Not called when a user creates a room.
 | 
						|
 | 
						|
        Args:
 | 
						|
            userid: The ID of the user wanting to join the room
 | 
						|
            room_id: The ID of the room the user wants to join
 | 
						|
            is_invited: Whether the user is invited into the room
 | 
						|
 | 
						|
        Returns:
 | 
						|
            NOT_SPAM if the operation is permitted, [Codes, Dict] otherwise.
 | 
						|
        """
 | 
						|
        for callback in self._user_may_join_room_callbacks:
 | 
						|
            with Measure(self.clock, f"{callback.__module__}.{callback.__qualname__}"):
 | 
						|
                res = await delay_cancellation(callback(user_id, room_id, is_invited))
 | 
						|
                # Normalize return values to `Codes` or `"NOT_SPAM"`.
 | 
						|
                if res is True or res is self.NOT_SPAM:
 | 
						|
                    continue
 | 
						|
                elif res is False:
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
                elif isinstance(res, synapse.api.errors.Codes):
 | 
						|
                    return res, {}
 | 
						|
                elif (
 | 
						|
                    isinstance(res, tuple)
 | 
						|
                    and len(res) == 2
 | 
						|
                    and isinstance(res[0], synapse.api.errors.Codes)
 | 
						|
                    and isinstance(res[1], dict)
 | 
						|
                ):
 | 
						|
                    return res
 | 
						|
                else:
 | 
						|
                    logger.warning(
 | 
						|
                        "Module returned invalid value, rejecting join as spam"
 | 
						|
                    )
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
 | 
						|
        # No spam-checker has rejected the request, let it pass.
 | 
						|
        return self.NOT_SPAM
 | 
						|
 | 
						|
    async def user_may_invite(
 | 
						|
        self, inviter_userid: str, invitee_userid: str, room_id: str
 | 
						|
    ) -> Union[Tuple[Codes, dict], Literal["NOT_SPAM"]]:
 | 
						|
        """Checks if a given user may send an invite
 | 
						|
 | 
						|
        Args:
 | 
						|
            inviter_userid: The user ID of the sender of the invitation
 | 
						|
            invitee_userid: The user ID targeted in the invitation
 | 
						|
            room_id: The room ID
 | 
						|
 | 
						|
        Returns:
 | 
						|
            NOT_SPAM if the operation is permitted, Codes otherwise.
 | 
						|
        """
 | 
						|
        for callback in self._user_may_invite_callbacks:
 | 
						|
            with Measure(self.clock, f"{callback.__module__}.{callback.__qualname__}"):
 | 
						|
                res = await delay_cancellation(
 | 
						|
                    callback(inviter_userid, invitee_userid, room_id)
 | 
						|
                )
 | 
						|
                # Normalize return values to `Codes` or `"NOT_SPAM"`.
 | 
						|
                if res is True or res is self.NOT_SPAM:
 | 
						|
                    continue
 | 
						|
                elif res is False:
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
                elif isinstance(res, synapse.api.errors.Codes):
 | 
						|
                    return res, {}
 | 
						|
                elif (
 | 
						|
                    isinstance(res, tuple)
 | 
						|
                    and len(res) == 2
 | 
						|
                    and isinstance(res[0], synapse.api.errors.Codes)
 | 
						|
                    and isinstance(res[1], dict)
 | 
						|
                ):
 | 
						|
                    return res
 | 
						|
                else:
 | 
						|
                    logger.warning(
 | 
						|
                        "Module returned invalid value, rejecting invite as spam"
 | 
						|
                    )
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
 | 
						|
        # No spam-checker has rejected the request, let it pass.
 | 
						|
        return self.NOT_SPAM
 | 
						|
 | 
						|
    async def user_may_send_3pid_invite(
 | 
						|
        self, inviter_userid: str, medium: str, address: str, room_id: str
 | 
						|
    ) -> Union[Tuple[Codes, dict], Literal["NOT_SPAM"]]:
 | 
						|
        """Checks if a given user may invite a given threepid into the room
 | 
						|
 | 
						|
        Note that if the threepid is already associated with a Matrix user ID, Synapse
 | 
						|
        will call user_may_invite with said user ID instead.
 | 
						|
 | 
						|
        Args:
 | 
						|
            inviter_userid: The user ID of the sender of the invitation
 | 
						|
            medium: The 3PID's medium (e.g. "email")
 | 
						|
            address: The 3PID's address (e.g. "alice@example.com")
 | 
						|
            room_id: The room ID
 | 
						|
 | 
						|
        Returns:
 | 
						|
            NOT_SPAM if the operation is permitted, Codes otherwise.
 | 
						|
        """
 | 
						|
        for callback in self._user_may_send_3pid_invite_callbacks:
 | 
						|
            with Measure(self.clock, f"{callback.__module__}.{callback.__qualname__}"):
 | 
						|
                res = await delay_cancellation(
 | 
						|
                    callback(inviter_userid, medium, address, room_id)
 | 
						|
                )
 | 
						|
                # Normalize return values to `Codes` or `"NOT_SPAM"`.
 | 
						|
                if res is True or res is self.NOT_SPAM:
 | 
						|
                    continue
 | 
						|
                elif res is False:
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
                elif isinstance(res, synapse.api.errors.Codes):
 | 
						|
                    return res, {}
 | 
						|
                elif (
 | 
						|
                    isinstance(res, tuple)
 | 
						|
                    and len(res) == 2
 | 
						|
                    and isinstance(res[0], synapse.api.errors.Codes)
 | 
						|
                    and isinstance(res[1], dict)
 | 
						|
                ):
 | 
						|
                    return res
 | 
						|
                else:
 | 
						|
                    logger.warning(
 | 
						|
                        "Module returned invalid value, rejecting 3pid invite as spam"
 | 
						|
                    )
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
 | 
						|
        return self.NOT_SPAM
 | 
						|
 | 
						|
    async def user_may_create_room(
 | 
						|
        self, userid: str
 | 
						|
    ) -> Union[Tuple[Codes, dict], Literal["NOT_SPAM"]]:
 | 
						|
        """Checks if a given user may create a room
 | 
						|
 | 
						|
        Args:
 | 
						|
            userid: The ID of the user attempting to create a room
 | 
						|
        """
 | 
						|
        for callback in self._user_may_create_room_callbacks:
 | 
						|
            with Measure(self.clock, f"{callback.__module__}.{callback.__qualname__}"):
 | 
						|
                res = await delay_cancellation(callback(userid))
 | 
						|
                if res is True or res is self.NOT_SPAM:
 | 
						|
                    continue
 | 
						|
                elif res is False:
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
                elif isinstance(res, synapse.api.errors.Codes):
 | 
						|
                    return res, {}
 | 
						|
                elif (
 | 
						|
                    isinstance(res, tuple)
 | 
						|
                    and len(res) == 2
 | 
						|
                    and isinstance(res[0], synapse.api.errors.Codes)
 | 
						|
                    and isinstance(res[1], dict)
 | 
						|
                ):
 | 
						|
                    return res
 | 
						|
                else:
 | 
						|
                    logger.warning(
 | 
						|
                        "Module returned invalid value, rejecting room creation as spam"
 | 
						|
                    )
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
 | 
						|
        return self.NOT_SPAM
 | 
						|
 | 
						|
    async def user_may_create_room_alias(
 | 
						|
        self, userid: str, room_alias: RoomAlias
 | 
						|
    ) -> Union[Tuple[Codes, dict], Literal["NOT_SPAM"]]:
 | 
						|
        """Checks if a given user may create a room alias
 | 
						|
 | 
						|
        Args:
 | 
						|
            userid: The ID of the user attempting to create a room alias
 | 
						|
            room_alias: The alias to be created
 | 
						|
 | 
						|
        """
 | 
						|
        for callback in self._user_may_create_room_alias_callbacks:
 | 
						|
            with Measure(self.clock, f"{callback.__module__}.{callback.__qualname__}"):
 | 
						|
                res = await delay_cancellation(callback(userid, room_alias))
 | 
						|
                if res is True or res is self.NOT_SPAM:
 | 
						|
                    continue
 | 
						|
                elif res is False:
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
                elif isinstance(res, synapse.api.errors.Codes):
 | 
						|
                    return res, {}
 | 
						|
                elif (
 | 
						|
                    isinstance(res, tuple)
 | 
						|
                    and len(res) == 2
 | 
						|
                    and isinstance(res[0], synapse.api.errors.Codes)
 | 
						|
                    and isinstance(res[1], dict)
 | 
						|
                ):
 | 
						|
                    return res
 | 
						|
                else:
 | 
						|
                    logger.warning(
 | 
						|
                        "Module returned invalid value, rejecting room create as spam"
 | 
						|
                    )
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
 | 
						|
        return self.NOT_SPAM
 | 
						|
 | 
						|
    async def user_may_publish_room(
 | 
						|
        self, userid: str, room_id: str
 | 
						|
    ) -> Union[Tuple[Codes, dict], Literal["NOT_SPAM"]]:
 | 
						|
        """Checks if a given user may publish a room to the directory
 | 
						|
 | 
						|
        Args:
 | 
						|
            userid: The user ID attempting to publish the room
 | 
						|
            room_id: The ID of the room that would be published
 | 
						|
        """
 | 
						|
        for callback in self._user_may_publish_room_callbacks:
 | 
						|
            with Measure(self.clock, f"{callback.__module__}.{callback.__qualname__}"):
 | 
						|
                res = await delay_cancellation(callback(userid, room_id))
 | 
						|
                if res is True or res is self.NOT_SPAM:
 | 
						|
                    continue
 | 
						|
                elif res is False:
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
                elif isinstance(res, synapse.api.errors.Codes):
 | 
						|
                    return res, {}
 | 
						|
                elif (
 | 
						|
                    isinstance(res, tuple)
 | 
						|
                    and len(res) == 2
 | 
						|
                    and isinstance(res[0], synapse.api.errors.Codes)
 | 
						|
                    and isinstance(res[1], dict)
 | 
						|
                ):
 | 
						|
                    return res
 | 
						|
                else:
 | 
						|
                    logger.warning(
 | 
						|
                        "Module returned invalid value, rejecting room publication as spam"
 | 
						|
                    )
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
 | 
						|
        return self.NOT_SPAM
 | 
						|
 | 
						|
    async def check_username_for_spam(self, user_profile: UserProfile) -> bool:
 | 
						|
        """Checks if a user ID or display name are considered "spammy" by this server.
 | 
						|
 | 
						|
        If the server considers a username spammy, then it will not be included in
 | 
						|
        user directory results.
 | 
						|
 | 
						|
        Args:
 | 
						|
            user_profile: The user information to check, it contains the keys:
 | 
						|
                * user_id
 | 
						|
                * display_name
 | 
						|
                * avatar_url
 | 
						|
 | 
						|
        Returns:
 | 
						|
            True if the user is spammy.
 | 
						|
        """
 | 
						|
        for callback in self._check_username_for_spam_callbacks:
 | 
						|
            with Measure(self.clock, f"{callback.__module__}.{callback.__qualname__}"):
 | 
						|
                # Make a copy of the user profile object to ensure the spam checker cannot
 | 
						|
                # modify it.
 | 
						|
                res = await delay_cancellation(callback(user_profile.copy()))
 | 
						|
            if res:
 | 
						|
                return True
 | 
						|
 | 
						|
        return False
 | 
						|
 | 
						|
    async def check_registration_for_spam(
 | 
						|
        self,
 | 
						|
        email_threepid: Optional[dict],
 | 
						|
        username: Optional[str],
 | 
						|
        request_info: Collection[Tuple[str, str]],
 | 
						|
        auth_provider_id: Optional[str] = None,
 | 
						|
    ) -> RegistrationBehaviour:
 | 
						|
        """Checks if we should allow the given registration request.
 | 
						|
 | 
						|
        Args:
 | 
						|
            email_threepid: The email threepid used for registering, if any
 | 
						|
            username: The request user name, if any
 | 
						|
            request_info: List of tuples of user agent and IP that
 | 
						|
                were used during the registration process.
 | 
						|
            auth_provider_id: The SSO IdP the user used, e.g "oidc", "saml",
 | 
						|
                "cas". If any. Note this does not include users registered
 | 
						|
                via a password provider.
 | 
						|
 | 
						|
        Returns:
 | 
						|
            Enum for how the request should be handled
 | 
						|
        """
 | 
						|
 | 
						|
        for callback in self._check_registration_for_spam_callbacks:
 | 
						|
            with Measure(self.clock, f"{callback.__module__}.{callback.__qualname__}"):
 | 
						|
                behaviour = await delay_cancellation(
 | 
						|
                    callback(email_threepid, username, request_info, auth_provider_id)
 | 
						|
                )
 | 
						|
            assert isinstance(behaviour, RegistrationBehaviour)
 | 
						|
            if behaviour != RegistrationBehaviour.ALLOW:
 | 
						|
                return behaviour
 | 
						|
 | 
						|
        return RegistrationBehaviour.ALLOW
 | 
						|
 | 
						|
    @trace
 | 
						|
    async def check_media_file_for_spam(
 | 
						|
        self, file_wrapper: ReadableFileWrapper, file_info: FileInfo
 | 
						|
    ) -> Union[Tuple[Codes, dict], Literal["NOT_SPAM"]]:
 | 
						|
        """Checks if a piece of newly uploaded media should be blocked.
 | 
						|
 | 
						|
        This will be called for local uploads, downloads of remote media, each
 | 
						|
        thumbnail generated for those, and web pages/images used for URL
 | 
						|
        previews.
 | 
						|
 | 
						|
        Note that care should be taken to not do blocking IO operations in the
 | 
						|
        main thread. For example, to get the contents of a file a module
 | 
						|
        should do::
 | 
						|
 | 
						|
            async def check_media_file_for_spam(
 | 
						|
                self, file: ReadableFileWrapper, file_info: FileInfo
 | 
						|
            ) -> Union[Codes, Literal["NOT_SPAM"]]:
 | 
						|
                buffer = BytesIO()
 | 
						|
                await file.write_chunks_to(buffer.write)
 | 
						|
 | 
						|
                if buffer.getvalue() == b"Hello World":
 | 
						|
                    return synapse.module_api.NOT_SPAM
 | 
						|
 | 
						|
                return Codes.FORBIDDEN
 | 
						|
 | 
						|
 | 
						|
        Args:
 | 
						|
            file: An object that allows reading the contents of the media.
 | 
						|
            file_info: Metadata about the file.
 | 
						|
        """
 | 
						|
 | 
						|
        for callback in self._check_media_file_for_spam_callbacks:
 | 
						|
            with Measure(self.clock, f"{callback.__module__}.{callback.__qualname__}"):
 | 
						|
                res = await delay_cancellation(callback(file_wrapper, file_info))
 | 
						|
                # Normalize return values to `Codes` or `"NOT_SPAM"`.
 | 
						|
                if res is False or res is self.NOT_SPAM:
 | 
						|
                    continue
 | 
						|
                elif res is True:
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
                elif isinstance(res, synapse.api.errors.Codes):
 | 
						|
                    return res, {}
 | 
						|
                elif (
 | 
						|
                    isinstance(res, tuple)
 | 
						|
                    and len(res) == 2
 | 
						|
                    and isinstance(res[0], synapse.api.errors.Codes)
 | 
						|
                    and isinstance(res[1], dict)
 | 
						|
                ):
 | 
						|
                    return res
 | 
						|
                else:
 | 
						|
                    logger.warning(
 | 
						|
                        "Module returned invalid value, rejecting media file as spam"
 | 
						|
                    )
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
 | 
						|
        return self.NOT_SPAM
 | 
						|
 | 
						|
    async def check_login_for_spam(
 | 
						|
        self,
 | 
						|
        user_id: str,
 | 
						|
        device_id: Optional[str],
 | 
						|
        initial_display_name: Optional[str],
 | 
						|
        request_info: Collection[Tuple[Optional[str], str]],
 | 
						|
        auth_provider_id: Optional[str] = None,
 | 
						|
    ) -> Union[Tuple[Codes, dict], Literal["NOT_SPAM"]]:
 | 
						|
        """Checks if we should allow the given registration request.
 | 
						|
 | 
						|
        Args:
 | 
						|
            user_id: The request user ID
 | 
						|
            request_info: List of tuples of user agent and IP that
 | 
						|
                were used during the registration process.
 | 
						|
            auth_provider_id: The SSO IdP the user used, e.g "oidc", "saml",
 | 
						|
                "cas". If any. Note this does not include users registered
 | 
						|
                via a password provider.
 | 
						|
 | 
						|
        Returns:
 | 
						|
            Enum for how the request should be handled
 | 
						|
        """
 | 
						|
 | 
						|
        for callback in self._check_login_for_spam_callbacks:
 | 
						|
            with Measure(self.clock, f"{callback.__module__}.{callback.__qualname__}"):
 | 
						|
                res = await delay_cancellation(
 | 
						|
                    callback(
 | 
						|
                        user_id,
 | 
						|
                        device_id,
 | 
						|
                        initial_display_name,
 | 
						|
                        request_info,
 | 
						|
                        auth_provider_id,
 | 
						|
                    )
 | 
						|
                )
 | 
						|
                # Normalize return values to `Codes` or `"NOT_SPAM"`.
 | 
						|
                if res is self.NOT_SPAM:
 | 
						|
                    continue
 | 
						|
                elif isinstance(res, synapse.api.errors.Codes):
 | 
						|
                    return res, {}
 | 
						|
                elif (
 | 
						|
                    isinstance(res, tuple)
 | 
						|
                    and len(res) == 2
 | 
						|
                    and isinstance(res[0], synapse.api.errors.Codes)
 | 
						|
                    and isinstance(res[1], dict)
 | 
						|
                ):
 | 
						|
                    return res
 | 
						|
                else:
 | 
						|
                    logger.warning(
 | 
						|
                        "Module returned invalid value, rejecting login as spam"
 | 
						|
                    )
 | 
						|
                    return synapse.api.errors.Codes.FORBIDDEN, {}
 | 
						|
 | 
						|
        return self.NOT_SPAM
 |