1 files changed, 168 insertions, 10 deletions
diff --git a/synapse/events/__init__.py b/synapse/events/__init__.py
index 12f1eb0a3e..20c1ab4203 100644
--- a/synapse/events/__init__.py
+++ b/synapse/events/__init__.py
@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2019 New Vector Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -18,6 +19,9 @@ from distutils.util import strtobool
 
 import six
 
+from unpaddedbase64 import encode_base64
+
+from synapse.api.constants import KNOWN_ROOM_VERSIONS, EventFormatVersions, RoomVersions
 from synapse.util.caches import intern_dict
 from synapse.util.frozenutils import freeze
 
@@ -41,8 +45,13 @@ class _EventInternalMetadata(object):
     def is_outlier(self):
         return getattr(self, "outlier", False)
 
-    def is_invite_from_remote(self):
-        return getattr(self, "invite_from_remote", False)
+    def is_out_of_band_membership(self):
+        """Whether this is an out of band membership, like an invite or an invite
+        rejection. This is needed as those events are marked as outliers, but
+        they still need to be processed as if they're new events (e.g. updating
+        invite state in the database, relaying to clients, etc).
+        """
+        return getattr(self, "out_of_band_membership", False)
 
     def get_send_on_behalf_of(self):
         """Whether this server should send the event on behalf of another server.
@@ -53,6 +62,21 @@ class _EventInternalMetadata(object):
         """
         return getattr(self, "send_on_behalf_of", None)
 
+    def need_to_check_redaction(self):
+        """Whether the redaction event needs to be rechecked when fetching
+        from the database.
+
+        Starting in room v3 redaction events are accepted up front, and later
+        checked to see if the redacter and redactee's domains match.
+
+        If the sender of the redaction event is allowed to redact any event
+        due to auth rules, then this will always return false.
+
+        Returns:
+            bool
+        """
+        return getattr(self, "recheck_redaction", False)
+
 
 def _event_dict_property(key):
     # We want to be able to use hasattr with the event dict properties.
@@ -159,8 +183,28 @@ class EventBase(object):
     def keys(self):
         return six.iterkeys(self._event_dict)
 
+    def prev_event_ids(self):
+        """Returns the list of prev event IDs. The order matches the order
+        specified in the event, though there is no meaning to it.
+
+        Returns:
+            list[str]: The list of event IDs of this event's prev_events
+        """
+        return [e for e, _ in self.prev_events]
+
+    def auth_event_ids(self):
+        """Returns the list of auth event IDs. The order matches the order
+        specified in the event, though there is no meaning to it.
+
+        Returns:
+            list[str]: The list of event IDs of this event's auth_events
+        """
+        return [e for e, _ in self.auth_events]
+
 
 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):
         event_dict = dict(event_dict)
 
@@ -195,22 +239,136 @@ class FrozenEvent(EventBase):
             rejected_reason=rejected_reason,
         )
 
-    @staticmethod
-    def from_event(event):
-        e = FrozenEvent(
-            event.get_pdu_json()
+    def __str__(self):
+        return self.__repr__()
+
+    def __repr__(self):
+        return "<FrozenEvent event_id='%s', type='%s', state_key='%s'>" % (
+            self.get("event_id", None),
+            self.get("type", None),
+            self.get("state_key", None),
+        )
+
+
+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):
+        event_dict = dict(event_dict)
+
+        # Signatures is a dict of dicts, and this is faster than doing a
+        # copy.deepcopy
+        signatures = {
+            name: {sig_id: sig for sig_id, sig in sigs.items()}
+            for name, sigs in event_dict.pop("signatures", {}).items()
+        }
+
+        assert "event_id" not in event_dict
+
+        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 = None
+        self.type = event_dict["type"]
+        if "state_key" in event_dict:
+            self.state_key = event_dict["state_key"]
+
+        super(FrozenEventV2, self).__init__(
+            frozen_dict,
+            signatures=signatures,
+            unsigned=unsigned,
+            internal_metadata_dict=internal_metadata_dict,
+            rejected_reason=rejected_reason,
         )
 
-        e.internal_metadata = event.internal_metadata
+    @property
+    def event_id(self):
+        # 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):
+        """Returns the list of prev event IDs. The order matches the order
+        specified in the event, though there is no meaning to it.
+
+        Returns:
+            list[str]: The list of event IDs of this event's prev_events
+        """
+        return self.prev_events
+
+    def auth_event_ids(self):
+        """Returns the list of auth event IDs. The order matches the order
+        specified in the event, though there is no meaning to it.
 
-        return e
+        Returns:
+            list[str]: The list of event IDs of this event's auth_events
+        """
+        return self.auth_events
 
     def __str__(self):
         return self.__repr__()
 
     def __repr__(self):
-        return "<FrozenEvent event_id='%s', type='%s', state_key='%s'>" % (
-            self.get("event_id", None),
+        return "<FrozenEventV2 event_id='%s', type='%s', state_key='%s'>" % (
+            self.event_id,
             self.get("type", None),
             self.get("state_key", None),
         )
+
+
+def room_version_to_event_format(room_version):
+    """Converts a room version string to the event format
+
+    Args:
+        room_version (str)
+
+    Returns:
+        int
+    """
+    if room_version not in KNOWN_ROOM_VERSIONS:
+        # We should have already checked version, so this should not happen
+        raise RuntimeError("Unrecognized room version %s" % (room_version,))
+
+    if room_version in (
+        RoomVersions.V1, RoomVersions.V2, RoomVersions.STATE_V2_TEST,
+    ):
+        return EventFormatVersions.V1
+    elif room_version in (RoomVersions.V3,):
+        return EventFormatVersions.V2
+    else:
+        raise RuntimeError("Unrecognized room version %s" % (room_version,))
+
+
+def event_type_from_format_version(format_version):
+    """Returns the python type to use to construct an Event object for the
+    given event format version.
+
+    Args:
+        format_version (int): The event format version
+
+    Returns:
+        type: A type that can be initialized as per the initializer of
+        `FrozenEvent`
+    """
+
+    if format_version == EventFormatVersions.V1:
+        return FrozenEvent
+    elif format_version == EventFormatVersions.V2:
+        return FrozenEventV2
+    else:
+        raise Exception(
+            "No event format %r" % (format_version,)
+        )