663 lines
23 KiB
Python
663 lines
23 KiB
Python
# Copyright 2014-2016 OpenMarket Ltd
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# Copyright 2019 New Vector Ltd
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# Copyright 2020 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 abc
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import collections.abc
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import os
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from typing import (
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TYPE_CHECKING,
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Any,
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Dict,
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Generic,
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Iterable,
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List,
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Optional,
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Sequence,
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Tuple,
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Type,
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TypeVar,
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Union,
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overload,
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)
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import attr
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from typing_extensions import Literal
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from unpaddedbase64 import encode_base64
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from synapse.api.constants import RelationTypes
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from synapse.api.room_versions import EventFormatVersions, RoomVersion, RoomVersions
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from synapse.types import JsonDict, RoomStreamToken
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from synapse.util.caches import intern_dict
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from synapse.util.frozenutils import freeze
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from synapse.util.stringutils import strtobool
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if TYPE_CHECKING:
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from synapse.events.builder import EventBuilder
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# Whether we should use frozen_dict in FrozenEvent. Using frozen_dicts prevents
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# bugs where we accidentally share e.g. signature dicts. However, converting a
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# dict to frozen_dicts is expensive.
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#
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# NOTE: This is overridden by the configuration by the Synapse worker apps, but
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# for the sake of tests, it is set here while it cannot be configured on the
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# homeserver object itself.
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USE_FROZEN_DICTS = strtobool(os.environ.get("SYNAPSE_USE_FROZEN_DICTS", "0"))
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T = TypeVar("T")
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# DictProperty (and DefaultDictProperty) require the classes they're used with to
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# have a _dict property to pull properties from.
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#
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# TODO _DictPropertyInstance should not include EventBuilder but due to
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# https://github.com/python/mypy/issues/5570 it thinks the DictProperty and
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# DefaultDictProperty get applied to EventBuilder when it is in a Union with
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# EventBase. This is the least invasive hack to get mypy to comply.
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#
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# Note that DictProperty/DefaultDictProperty cannot actually be used with
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# EventBuilder as it lacks a _dict property.
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_DictPropertyInstance = Union["_EventInternalMetadata", "EventBase", "EventBuilder"]
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class DictProperty(Generic[T]):
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"""An object property which delegates to the `_dict` within its parent object."""
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__slots__ = ["key"]
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def __init__(self, key: str):
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self.key = key
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@overload
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def __get__(
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self,
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instance: Literal[None],
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owner: Optional[Type[_DictPropertyInstance]] = None,
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) -> "DictProperty":
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...
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@overload
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def __get__(
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self,
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instance: _DictPropertyInstance,
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owner: Optional[Type[_DictPropertyInstance]] = None,
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) -> T:
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...
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def __get__(
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self,
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instance: Optional[_DictPropertyInstance],
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owner: Optional[Type[_DictPropertyInstance]] = None,
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) -> Union[T, "DictProperty"]:
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# if the property is accessed as a class property rather than an instance
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# property, return the property itself rather than the value
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if instance is None:
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return self
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try:
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assert isinstance(instance, (EventBase, _EventInternalMetadata))
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return instance._dict[self.key]
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except KeyError as e1:
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# We want this to look like a regular attribute error (mostly so that
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# hasattr() works correctly), so we convert the KeyError into an
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# AttributeError.
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#
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# To exclude the KeyError from the traceback, we explicitly
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# 'raise from e1.__context__' (which is better than 'raise from None',
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# because that would omit any *earlier* exceptions).
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#
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raise AttributeError(
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"'%s' has no '%s' property" % (type(instance), self.key)
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) from e1.__context__
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def __set__(self, instance: _DictPropertyInstance, v: T) -> None:
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assert isinstance(instance, (EventBase, _EventInternalMetadata))
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instance._dict[self.key] = v
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def __delete__(self, instance: _DictPropertyInstance) -> None:
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assert isinstance(instance, (EventBase, _EventInternalMetadata))
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try:
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del instance._dict[self.key]
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except KeyError as e1:
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raise AttributeError(
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"'%s' has no '%s' property" % (type(instance), self.key)
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) from e1.__context__
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class DefaultDictProperty(DictProperty, Generic[T]):
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"""An extension of DictProperty which provides a default if the property is
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not present in the parent's _dict.
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Note that this means that hasattr() on the property always returns True.
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"""
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__slots__ = ["default"]
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def __init__(self, key: str, default: T):
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super().__init__(key)
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self.default = default
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@overload
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def __get__(
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self,
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instance: Literal[None],
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owner: Optional[Type[_DictPropertyInstance]] = None,
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) -> "DefaultDictProperty":
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...
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@overload
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def __get__(
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self,
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instance: _DictPropertyInstance,
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owner: Optional[Type[_DictPropertyInstance]] = None,
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) -> T:
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...
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def __get__(
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self,
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instance: Optional[_DictPropertyInstance],
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owner: Optional[Type[_DictPropertyInstance]] = None,
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) -> Union[T, "DefaultDictProperty"]:
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if instance is None:
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return self
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assert isinstance(instance, (EventBase, _EventInternalMetadata))
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return instance._dict.get(self.key, self.default)
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class _EventInternalMetadata:
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__slots__ = ["_dict", "stream_ordering", "outlier"]
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def __init__(self, internal_metadata_dict: JsonDict):
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# we have to copy the dict, because it turns out that the same dict is
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# reused. TODO: fix that
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self._dict = dict(internal_metadata_dict)
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# the stream ordering of this event. None, until it has been persisted.
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self.stream_ordering: Optional[int] = None
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# whether this event is an outlier (ie, whether we have the state at that point
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# in the DAG)
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self.outlier = False
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out_of_band_membership: DictProperty[bool] = DictProperty("out_of_band_membership")
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send_on_behalf_of: DictProperty[str] = DictProperty("send_on_behalf_of")
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recheck_redaction: DictProperty[bool] = DictProperty("recheck_redaction")
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soft_failed: DictProperty[bool] = DictProperty("soft_failed")
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proactively_send: DictProperty[bool] = DictProperty("proactively_send")
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redacted: DictProperty[bool] = DictProperty("redacted")
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txn_id: DictProperty[str] = DictProperty("txn_id")
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token_id: DictProperty[int] = DictProperty("token_id")
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historical: DictProperty[bool] = DictProperty("historical")
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# XXX: These are set by StreamWorkerStore._set_before_and_after.
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# I'm pretty sure that these are never persisted to the database, so shouldn't
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# be here
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before: DictProperty[RoomStreamToken] = DictProperty("before")
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after: DictProperty[RoomStreamToken] = DictProperty("after")
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order: DictProperty[Tuple[int, int]] = DictProperty("order")
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def get_dict(self) -> JsonDict:
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return dict(self._dict)
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def is_outlier(self) -> bool:
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return self.outlier
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def is_out_of_band_membership(self) -> bool:
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"""Whether this event is an out-of-band membership.
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OOB memberships are a special case of outlier events: they are membership events
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for federated rooms that we aren't full members of. Examples include invites
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received over federation, and rejections for such invites.
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The concept of an OOB membership is needed because these events need to be
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processed as if they're new regular events (e.g. updating membership state in
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the database, relaying to clients via /sync, etc) despite being outliers.
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See also https://matrix-org.github.io/synapse/develop/development/room-dag-concepts.html#out-of-band-membership-events.
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(Added in synapse 0.99.0, so may be unreliable for events received before that)
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"""
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return self._dict.get("out_of_band_membership", False)
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def get_send_on_behalf_of(self) -> Optional[str]:
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"""Whether this server should send the event on behalf of another server.
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This is used by the federation "send_join" API to forward the initial join
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event for a server in the room.
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returns a str with the name of the server this event is sent on behalf of.
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"""
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return self._dict.get("send_on_behalf_of")
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def need_to_check_redaction(self) -> bool:
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"""Whether the redaction event needs to be rechecked when fetching
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from the database.
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Starting in room v3 redaction events are accepted up front, and later
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checked to see if the redacter and redactee's domains match.
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If the sender of the redaction event is allowed to redact any event
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due to auth rules, then this will always return false.
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"""
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return self._dict.get("recheck_redaction", False)
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def is_soft_failed(self) -> bool:
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"""Whether the event has been soft failed.
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Soft failed events should be handled as usual, except:
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1. They should not go down sync or event streams, or generally
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sent to clients.
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2. They should not be added to the forward extremities (and
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therefore not to current state).
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"""
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return self._dict.get("soft_failed", False)
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def should_proactively_send(self) -> bool:
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"""Whether the event, if ours, should be sent to other clients and
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servers.
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This is used for sending dummy events internally. Servers and clients
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can still explicitly fetch the event.
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"""
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return self._dict.get("proactively_send", True)
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def is_redacted(self) -> bool:
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"""Whether the event has been redacted.
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This is used for efficiently checking whether an event has been
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marked as redacted without needing to make another database call.
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"""
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return self._dict.get("redacted", False)
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def is_historical(self) -> bool:
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"""Whether this is a historical message.
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This is used by the batchsend historical message endpoint and
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is needed to and mark the event as backfilled and skip some checks
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like push notifications.
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"""
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return self._dict.get("historical", False)
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class EventBase(metaclass=abc.ABCMeta):
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@property
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@abc.abstractmethod
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def format_version(self) -> int:
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"""The EventFormatVersion implemented by this event"""
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...
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def __init__(
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self,
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event_dict: JsonDict,
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room_version: RoomVersion,
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signatures: Dict[str, Dict[str, str]],
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unsigned: JsonDict,
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internal_metadata_dict: JsonDict,
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rejected_reason: Optional[str],
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):
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assert room_version.event_format == self.format_version
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self.room_version = room_version
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self.signatures = signatures
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self.unsigned = unsigned
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self.rejected_reason = rejected_reason
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self._dict = event_dict
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self.internal_metadata = _EventInternalMetadata(internal_metadata_dict)
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depth: DictProperty[int] = DictProperty("depth")
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content: DictProperty[JsonDict] = DictProperty("content")
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hashes: DictProperty[Dict[str, str]] = DictProperty("hashes")
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origin: DictProperty[str] = DictProperty("origin")
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origin_server_ts: DictProperty[int] = DictProperty("origin_server_ts")
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redacts: DefaultDictProperty[Optional[str]] = DefaultDictProperty("redacts", None)
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room_id: DictProperty[str] = DictProperty("room_id")
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sender: DictProperty[str] = DictProperty("sender")
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# TODO state_key should be Optional[str]. This is generally asserted in Synapse
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# by calling is_state() first (which ensures it is not None), but it is hard (not possible?)
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# to properly annotate that calling is_state() asserts that state_key exists
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# and is non-None. It would be better to replace such direct references with
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# get_state_key() (and a check for None).
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state_key: DictProperty[str] = DictProperty("state_key")
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type: DictProperty[str] = DictProperty("type")
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user_id: DictProperty[str] = DictProperty("sender")
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@property
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def event_id(self) -> str:
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raise NotImplementedError()
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@property
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def membership(self) -> str:
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return self.content["membership"]
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def is_state(self) -> bool:
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return self.get_state_key() is not None
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def get_state_key(self) -> Optional[str]:
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"""Get the state key of this event, or None if it's not a state event"""
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return self._dict.get("state_key")
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def get_dict(self) -> JsonDict:
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d = dict(self._dict)
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d.update({"signatures": self.signatures, "unsigned": dict(self.unsigned)})
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return d
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def get(self, key: str, default: Optional[Any] = None) -> Any:
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return self._dict.get(key, default)
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def get_internal_metadata_dict(self) -> JsonDict:
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return self.internal_metadata.get_dict()
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def get_pdu_json(self, time_now: Optional[int] = None) -> JsonDict:
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pdu_json = self.get_dict()
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if time_now is not None and "age_ts" in pdu_json["unsigned"]:
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age = time_now - pdu_json["unsigned"]["age_ts"]
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pdu_json.setdefault("unsigned", {})["age"] = int(age)
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del pdu_json["unsigned"]["age_ts"]
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# This may be a frozen event
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pdu_json["unsigned"].pop("redacted_because", None)
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return pdu_json
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def get_templated_pdu_json(self) -> JsonDict:
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"""
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Return a JSON object suitable for a templated event, as used in the
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make_{join,leave,knock} workflow.
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"""
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# By using _dict directly we don't pull in signatures/unsigned.
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template_json = dict(self._dict)
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# The hashes (similar to the signature) need to be recalculated by the
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# joining/leaving/knocking server after (potentially) modifying the
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# event.
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template_json.pop("hashes")
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return template_json
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def __getitem__(self, field: str) -> Optional[Any]:
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return self._dict[field]
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def __contains__(self, field: str) -> bool:
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return field in self._dict
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def items(self) -> List[Tuple[str, Optional[Any]]]:
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return list(self._dict.items())
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def keys(self) -> Iterable[str]:
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return self._dict.keys()
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def prev_event_ids(self) -> Sequence[str]:
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"""Returns the list of prev event IDs. The order matches the order
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specified in the event, though there is no meaning to it.
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Returns:
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The list of event IDs of this event's prev_events
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"""
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return [e for e, _ in self._dict["prev_events"]]
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def auth_event_ids(self) -> Sequence[str]:
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"""Returns the list of auth event IDs. The order matches the order
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specified in the event, though there is no meaning to it.
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Returns:
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The list of event IDs of this event's auth_events
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"""
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return [e for e, _ in self._dict["auth_events"]]
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def freeze(self) -> None:
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"""'Freeze' the event dict, so it cannot be modified by accident"""
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# this will be a no-op if the event dict is already frozen.
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self._dict = freeze(self._dict)
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def __str__(self) -> str:
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return self.__repr__()
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def __repr__(self) -> str:
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rejection = f"REJECTED={self.rejected_reason}, " if self.rejected_reason else ""
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return (
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f"<{self.__class__.__name__} "
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f"{rejection}"
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f"event_id={self.event_id}, "
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f"type={self.get('type')}, "
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f"state_key={self.get('state_key')}, "
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f"outlier={self.internal_metadata.is_outlier()}"
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">"
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)
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class FrozenEvent(EventBase):
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format_version = EventFormatVersions.ROOM_V1_V2 # All events of this type are V1
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def __init__(
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self,
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event_dict: JsonDict,
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room_version: RoomVersion,
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internal_metadata_dict: Optional[JsonDict] = None,
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rejected_reason: Optional[str] = None,
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):
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internal_metadata_dict = internal_metadata_dict or {}
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event_dict = dict(event_dict)
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# Signatures is a dict of dicts, and this is faster than doing a
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# copy.deepcopy
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signatures = {
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name: {sig_id: sig for sig_id, sig in sigs.items()}
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for name, sigs in event_dict.pop("signatures", {}).items()
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}
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unsigned = dict(event_dict.pop("unsigned", {}))
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# We intern these strings because they turn up a lot (especially when
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# caching).
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event_dict = intern_dict(event_dict)
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if USE_FROZEN_DICTS:
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frozen_dict = freeze(event_dict)
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else:
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frozen_dict = event_dict
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self._event_id = event_dict["event_id"]
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super().__init__(
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frozen_dict,
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room_version=room_version,
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signatures=signatures,
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unsigned=unsigned,
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internal_metadata_dict=internal_metadata_dict,
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rejected_reason=rejected_reason,
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)
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@property
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def event_id(self) -> str:
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return self._event_id
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class FrozenEventV2(EventBase):
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format_version = EventFormatVersions.ROOM_V3 # All events of this type are V2
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def __init__(
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self,
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event_dict: JsonDict,
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room_version: RoomVersion,
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internal_metadata_dict: Optional[JsonDict] = None,
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rejected_reason: Optional[str] = None,
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):
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internal_metadata_dict = internal_metadata_dict or {}
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event_dict = dict(event_dict)
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# Signatures is a dict of dicts, and this is faster than doing a
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# copy.deepcopy
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signatures = {
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name: {sig_id: sig for sig_id, sig in sigs.items()}
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for name, sigs in event_dict.pop("signatures", {}).items()
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}
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assert "event_id" not in event_dict
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unsigned = dict(event_dict.pop("unsigned", {}))
|
|
|
|
# We intern these strings because they turn up a lot (especially when
|
|
# caching).
|
|
event_dict = intern_dict(event_dict)
|
|
|
|
if USE_FROZEN_DICTS:
|
|
frozen_dict = freeze(event_dict)
|
|
else:
|
|
frozen_dict = event_dict
|
|
|
|
self._event_id: Optional[str] = None
|
|
|
|
super().__init__(
|
|
frozen_dict,
|
|
room_version=room_version,
|
|
signatures=signatures,
|
|
unsigned=unsigned,
|
|
internal_metadata_dict=internal_metadata_dict,
|
|
rejected_reason=rejected_reason,
|
|
)
|
|
|
|
@property
|
|
def event_id(self) -> str:
|
|
# We have to import this here as otherwise we get an import loop which
|
|
# is hard to break.
|
|
from synapse.crypto.event_signing import compute_event_reference_hash
|
|
|
|
if self._event_id:
|
|
return self._event_id
|
|
self._event_id = "$" + encode_base64(compute_event_reference_hash(self)[1])
|
|
return self._event_id
|
|
|
|
def prev_event_ids(self) -> Sequence[str]:
|
|
"""Returns the list of prev event IDs. The order matches the order
|
|
specified in the event, though there is no meaning to it.
|
|
|
|
Returns:
|
|
The list of event IDs of this event's prev_events
|
|
"""
|
|
return self._dict["prev_events"]
|
|
|
|
def auth_event_ids(self) -> Sequence[str]:
|
|
"""Returns the list of auth event IDs. The order matches the order
|
|
specified in the event, though there is no meaning to it.
|
|
|
|
Returns:
|
|
The list of event IDs of this event's auth_events
|
|
"""
|
|
return self._dict["auth_events"]
|
|
|
|
|
|
class FrozenEventV3(FrozenEventV2):
|
|
"""FrozenEventV3, which differs from FrozenEventV2 only in the event_id format"""
|
|
|
|
format_version = EventFormatVersions.ROOM_V4_PLUS # All events of this type are V3
|
|
|
|
@property
|
|
def event_id(self) -> str:
|
|
# We have to import this here as otherwise we get an import loop which
|
|
# is hard to break.
|
|
from synapse.crypto.event_signing import compute_event_reference_hash
|
|
|
|
if self._event_id:
|
|
return self._event_id
|
|
self._event_id = "$" + encode_base64(
|
|
compute_event_reference_hash(self)[1], urlsafe=True
|
|
)
|
|
return self._event_id
|
|
|
|
|
|
def _event_type_from_format_version(
|
|
format_version: int,
|
|
) -> Type[Union[FrozenEvent, FrozenEventV2, FrozenEventV3]]:
|
|
"""Returns the python type to use to construct an Event object for the
|
|
given event format version.
|
|
|
|
Args:
|
|
format_version: The event format version
|
|
|
|
Returns:
|
|
type: A type that can be initialized as per the initializer of
|
|
`FrozenEvent`
|
|
"""
|
|
|
|
if format_version == EventFormatVersions.ROOM_V1_V2:
|
|
return FrozenEvent
|
|
elif format_version == EventFormatVersions.ROOM_V3:
|
|
return FrozenEventV2
|
|
elif format_version == EventFormatVersions.ROOM_V4_PLUS:
|
|
return FrozenEventV3
|
|
else:
|
|
raise Exception("No event format %r" % (format_version,))
|
|
|
|
|
|
def make_event_from_dict(
|
|
event_dict: JsonDict,
|
|
room_version: RoomVersion = RoomVersions.V1,
|
|
internal_metadata_dict: Optional[JsonDict] = None,
|
|
rejected_reason: Optional[str] = None,
|
|
) -> EventBase:
|
|
"""Construct an EventBase from the given event dict"""
|
|
event_type = _event_type_from_format_version(room_version.event_format)
|
|
return event_type(
|
|
event_dict, room_version, internal_metadata_dict or {}, rejected_reason
|
|
)
|
|
|
|
|
|
@attr.s(slots=True, frozen=True, auto_attribs=True)
|
|
class _EventRelation:
|
|
# The target event of the relation.
|
|
parent_id: str
|
|
# The relation type.
|
|
rel_type: str
|
|
# The aggregation key. Will be None if the rel_type is not m.annotation or is
|
|
# not a string.
|
|
aggregation_key: Optional[str]
|
|
|
|
|
|
def relation_from_event(event: EventBase) -> Optional[_EventRelation]:
|
|
"""
|
|
Attempt to parse relation information an event.
|
|
|
|
Returns:
|
|
The event relation information, if it is valid. None, otherwise.
|
|
"""
|
|
relation = event.content.get("m.relates_to")
|
|
if not relation or not isinstance(relation, collections.abc.Mapping):
|
|
# No relation information.
|
|
return None
|
|
|
|
# Relations must have a type and parent event ID.
|
|
rel_type = relation.get("rel_type")
|
|
if not isinstance(rel_type, str):
|
|
return None
|
|
|
|
parent_id = relation.get("event_id")
|
|
if not isinstance(parent_id, str):
|
|
return None
|
|
|
|
# Annotations have a key field.
|
|
aggregation_key = None
|
|
if rel_type == RelationTypes.ANNOTATION:
|
|
aggregation_key = relation.get("key")
|
|
if not isinstance(aggregation_key, str):
|
|
aggregation_key = None
|
|
|
|
return _EventRelation(parent_id, rel_type, aggregation_key)
|