Store room_versions in EventBase objects (#6875)

This is a bit fiddly because it all has to be done on one fell swoop:

* Wherever we create a new event, pass in the room version (and check it matches the format version)
* When we prune an event, use the room version of the unpruned event to create the pruned version.
* When we pass an event over the replication protocol, pass the room version over alongside it, and use it when deserialising the event again.
This commit is contained in:
Richard van der Hoff 2020-03-05 15:46:44 +00:00 committed by GitHub
parent fe678a0900
commit 78a15b1f9d
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5 changed files with 63 additions and 32 deletions

1
changelog.d/6875.misc Normal file
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@ -0,0 +1 @@
Refactoring work in preparation for changing the event redaction algorithm.

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@ -15,9 +15,10 @@
# See the License for the specific language governing permissions and
# limitations under the License.
import abc
import os
from distutils.util import strtobool
from typing import Optional, Type
from typing import Dict, Optional, Type
import six
@ -199,15 +200,25 @@ class _EventInternalMetadata(object):
return self._dict.get("redacted", False)
class EventBase(object):
class EventBase(metaclass=abc.ABCMeta):
@property
@abc.abstractmethod
def format_version(self) -> int:
"""The EventFormatVersion implemented by this event"""
...
def __init__(
self,
event_dict,
signatures={},
unsigned={},
internal_metadata_dict={},
rejected_reason=None,
event_dict: JsonDict,
room_version: RoomVersion,
signatures: Dict[str, Dict[str, str]],
unsigned: JsonDict,
internal_metadata_dict: JsonDict,
rejected_reason: Optional[str],
):
assert room_version.event_format == self.format_version
self.room_version = room_version
self.signatures = signatures
self.unsigned = unsigned
self.rejected_reason = rejected_reason
@ -303,7 +314,13 @@ class EventBase(object):
class FrozenEvent(EventBase):
format_version = EventFormatVersions.V1 # All events of this type are V1
def __init__(self, event_dict, internal_metadata_dict={}, rejected_reason=None):
def __init__(
self,
event_dict: JsonDict,
room_version: RoomVersion,
internal_metadata_dict: JsonDict = {},
rejected_reason: Optional[str] = None,
):
event_dict = dict(event_dict)
# Signatures is a dict of dicts, and this is faster than doing a
@ -326,8 +343,9 @@ class FrozenEvent(EventBase):
self._event_id = event_dict["event_id"]
super(FrozenEvent, self).__init__(
super().__init__(
frozen_dict,
room_version=room_version,
signatures=signatures,
unsigned=unsigned,
internal_metadata_dict=internal_metadata_dict,
@ -352,7 +370,13 @@ class FrozenEvent(EventBase):
class FrozenEventV2(EventBase):
format_version = EventFormatVersions.V2 # All events of this type are V2
def __init__(self, event_dict, internal_metadata_dict={}, rejected_reason=None):
def __init__(
self,
event_dict: JsonDict,
room_version: RoomVersion,
internal_metadata_dict: JsonDict = {},
rejected_reason: Optional[str] = None,
):
event_dict = dict(event_dict)
# Signatures is a dict of dicts, and this is faster than doing a
@ -377,8 +401,9 @@ class FrozenEventV2(EventBase):
self._event_id = None
super(FrozenEventV2, self).__init__(
super().__init__(
frozen_dict,
room_version=room_version,
signatures=signatures,
unsigned=unsigned,
internal_metadata_dict=internal_metadata_dict,
@ -445,7 +470,7 @@ class FrozenEventV3(FrozenEventV2):
return self._event_id
def event_type_from_format_version(format_version: int) -> Type[EventBase]:
def _event_type_from_format_version(format_version: int) -> Type[EventBase]:
"""Returns the python type to use to construct an Event object for the
given event format version.
@ -474,5 +499,5 @@ def make_event_from_dict(
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, internal_metadata_dict, rejected_reason)
event_type = _event_type_from_format_version(room_version.event_format)
return event_type(event_dict, room_version, internal_metadata_dict, rejected_reason)

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@ -35,26 +35,20 @@ from . import EventBase
SPLIT_FIELD_REGEX = re.compile(r"(?<!\\)\.")
def prune_event(event):
def prune_event(event: EventBase) -> EventBase:
""" Returns a pruned version of the given event, which removes all keys we
don't know about or think could potentially be dodgy.
This is used when we "redact" an event. We want to remove all fields that
the user has specified, but we do want to keep necessary information like
type, state_key etc.
Args:
event (FrozenEvent)
Returns:
FrozenEvent
"""
pruned_event_dict = prune_event_dict(event.get_dict())
from . import event_type_from_format_version
from . import make_event_from_dict
pruned_event = event_type_from_format_version(event.format_version)(
pruned_event_dict, event.internal_metadata.get_dict()
pruned_event = make_event_from_dict(
pruned_event_dict, event.room_version, event.internal_metadata.get_dict()
)
# Mark the event as redacted

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@ -18,7 +18,7 @@ import logging
from twisted.internet import defer
from synapse.api.room_versions import KNOWN_ROOM_VERSIONS
from synapse.events import event_type_from_format_version
from synapse.events import make_event_from_dict
from synapse.events.snapshot import EventContext
from synapse.http.servlet import parse_json_object_from_request
from synapse.replication.http._base import ReplicationEndpoint
@ -38,6 +38,9 @@ class ReplicationFederationSendEventsRestServlet(ReplicationEndpoint):
{
"events": [{
"event": { .. serialized event .. },
"room_version": .., // "1", "2", "3", etc: the version of the room
// containing the event
"event_format_version": .., // 1,2,3 etc: the event format version
"internal_metadata": { .. serialized internal_metadata .. },
"rejected_reason": .., // The event.rejected_reason field
"context": { .. serialized event context .. },
@ -73,6 +76,7 @@ class ReplicationFederationSendEventsRestServlet(ReplicationEndpoint):
event_payloads.append(
{
"event": event.get_pdu_json(),
"room_version": event.room_version.identifier,
"event_format_version": event.format_version,
"internal_metadata": event.internal_metadata.get_dict(),
"rejected_reason": event.rejected_reason,
@ -95,12 +99,13 @@ class ReplicationFederationSendEventsRestServlet(ReplicationEndpoint):
event_and_contexts = []
for event_payload in event_payloads:
event_dict = event_payload["event"]
format_ver = event_payload["event_format_version"]
room_ver = KNOWN_ROOM_VERSIONS[event_payload["room_version"]]
internal_metadata = event_payload["internal_metadata"]
rejected_reason = event_payload["rejected_reason"]
EventType = event_type_from_format_version(format_ver)
event = EventType(event_dict, internal_metadata, rejected_reason)
event = make_event_from_dict(
event_dict, room_ver, internal_metadata, rejected_reason
)
context = EventContext.deserialize(
self.storage, event_payload["context"]

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@ -17,7 +17,8 @@ import logging
from twisted.internet import defer
from synapse.events import event_type_from_format_version
from synapse.api.room_versions import KNOWN_ROOM_VERSIONS
from synapse.events import make_event_from_dict
from synapse.events.snapshot import EventContext
from synapse.http.servlet import parse_json_object_from_request
from synapse.replication.http._base import ReplicationEndpoint
@ -37,6 +38,9 @@ class ReplicationSendEventRestServlet(ReplicationEndpoint):
{
"event": { .. serialized event .. },
"room_version": .., // "1", "2", "3", etc: the version of the room
// containing the event
"event_format_version": .., // 1,2,3 etc: the event format version
"internal_metadata": { .. serialized internal_metadata .. },
"rejected_reason": .., // The event.rejected_reason field
"context": { .. serialized event context .. },
@ -77,6 +81,7 @@ class ReplicationSendEventRestServlet(ReplicationEndpoint):
payload = {
"event": event.get_pdu_json(),
"room_version": event.room_version.identifier,
"event_format_version": event.format_version,
"internal_metadata": event.internal_metadata.get_dict(),
"rejected_reason": event.rejected_reason,
@ -93,12 +98,13 @@ class ReplicationSendEventRestServlet(ReplicationEndpoint):
content = parse_json_object_from_request(request)
event_dict = content["event"]
format_ver = content["event_format_version"]
room_ver = KNOWN_ROOM_VERSIONS[content["room_version"]]
internal_metadata = content["internal_metadata"]
rejected_reason = content["rejected_reason"]
EventType = event_type_from_format_version(format_ver)
event = EventType(event_dict, internal_metadata, rejected_reason)
event = make_event_from_dict(
event_dict, room_ver, internal_metadata, rejected_reason
)
requester = Requester.deserialize(self.store, content["requester"])
context = EventContext.deserialize(self.storage, content["context"])