diff --git a/synapse/events/builder.py b/synapse/events/builder.py
index e662eaef10..06e01be918 100644
--- a/synapse/events/builder.py
+++ b/synapse/events/builder.py
@@ -13,63 +13,270 @@
# See the License for the specific language governing permissions and
# limitations under the License.
-import copy
+import attr
+from twisted.internet import defer
+
+from synapse.api.constants import (
+ KNOWN_EVENT_FORMAT_VERSIONS,
+ KNOWN_ROOM_VERSIONS,
+ MAX_DEPTH,
+ EventFormatVersions,
+)
+from synapse.crypto.event_signing import add_hashes_and_signatures
from synapse.types import EventID
from synapse.util.stringutils import random_string
-from . import EventBase, FrozenEvent, _event_dict_property
+from . import (
+ _EventInternalMetadata,
+ event_type_from_format_version,
+ room_version_to_event_format,
+)
+
+
+@attr.s(slots=True, cmp=False, frozen=True)
+class EventBuilder(object):
+ """A format independent event builder used to build up the event content
+ before signing the event.
+
+ (Note that while objects of this class are frozen, the
+ content/unsigned/internal_metadata fields are still mutable)
+
+ Attributes:
+ format_version (int): Event format version
+ room_id (str)
+ type (str)
+ sender (str)
+ content (dict)
+ unsigned (dict)
+ internal_metadata (_EventInternalMetadata)
+
+ _state (StateHandler)
+ _auth (synapse.api.Auth)
+ _store (DataStore)
+ _clock (Clock)
+ _hostname (str): The hostname of the server creating the event
+ _signing_key: The signing key to use to sign the event as the server
+ """
+
+ _state = attr.ib()
+ _auth = attr.ib()
+ _store = attr.ib()
+ _clock = attr.ib()
+ _hostname = attr.ib()
+ _signing_key = attr.ib()
+
+ format_version = attr.ib()
+
+ room_id = attr.ib()
+ type = attr.ib()
+ sender = attr.ib()
+
+ content = attr.ib(default=attr.Factory(dict))
+ unsigned = attr.ib(default=attr.Factory(dict))
+
+ # These only exist on a subset of events, so they raise AttributeError if
+ # someone tries to get them when they don't exist.
+ _state_key = attr.ib(default=None)
+ _redacts = attr.ib(default=None)
+ internal_metadata = attr.ib(default=attr.Factory(lambda: _EventInternalMetadata({})))
-class EventBuilder(EventBase):
- def __init__(self, key_values={}, internal_metadata_dict={}):
- signatures = copy.deepcopy(key_values.pop("signatures", {}))
- unsigned = copy.deepcopy(key_values.pop("unsigned", {}))
+ @property
+ def state_key(self):
+ if self._state_key is not None:
+ return self._state_key
- super(EventBuilder, self).__init__(
- key_values,
- signatures=signatures,
- unsigned=unsigned,
- internal_metadata_dict=internal_metadata_dict,
+ raise AttributeError("state_key")
+
+ def is_state(self):
+ return self._state_key is not None
+
+ @defer.inlineCallbacks
+ def build(self, prev_event_ids):
+ """Transform into a fully signed and hashed event
+
+ Args:
+ prev_event_ids (list[str]): The event IDs to use as the prev events
+
+ Returns:
+ Deferred[FrozenEvent]
+ """
+
+ state_ids = yield self._state.get_current_state_ids(
+ self.room_id, prev_event_ids,
+ )
+ auth_ids = yield self._auth.compute_auth_events(
+ self, state_ids,
)
- event_id = _event_dict_property("event_id")
- state_key = _event_dict_property("state_key")
- type = _event_dict_property("type")
+ if self.format_version == EventFormatVersions.V1:
+ auth_events = yield self._store.add_event_hashes(auth_ids)
+ prev_events = yield self._store.add_event_hashes(prev_event_ids)
+ else:
+ auth_events = auth_ids
+ prev_events = prev_event_ids
+
+ old_depth = yield self._store.get_max_depth_of(
+ prev_event_ids,
+ )
+ depth = old_depth + 1
+
+ # we cap depth of generated events, to ensure that they are not
+ # rejected by other servers (and so that they can be persisted in
+ # the db)
+ depth = min(depth, MAX_DEPTH)
+
+ event_dict = {
+ "auth_events": auth_events,
+ "prev_events": prev_events,
+ "type": self.type,
+ "room_id": self.room_id,
+ "sender": self.sender,
+ "content": self.content,
+ "unsigned": self.unsigned,
+ "depth": depth,
+ "prev_state": [],
+ }
+
+ if self.is_state():
+ event_dict["state_key"] = self._state_key
- def build(self):
- return FrozenEvent.from_event(self)
+ if self._redacts is not None:
+ event_dict["redacts"] = self._redacts
+
+ defer.returnValue(
+ create_local_event_from_event_dict(
+ clock=self._clock,
+ hostname=self._hostname,
+ signing_key=self._signing_key,
+ format_version=self.format_version,
+ event_dict=event_dict,
+ internal_metadata_dict=self.internal_metadata.get_dict(),
+ )
+ )
class EventBuilderFactory(object):
- def __init__(self, clock, hostname):
- self.clock = clock
- self.hostname = hostname
+ def __init__(self, hs):
+ self.clock = hs.get_clock()
+ self.hostname = hs.hostname
+ self.signing_key = hs.config.signing_key[0]
+
+ self.store = hs.get_datastore()
+ self.state = hs.get_state_handler()
+ self.auth = hs.get_auth()
+
+ def new(self, room_version, key_values):
+ """Generate an event builder appropriate for the given room version
+
+ Args:
+ room_version (str): Version of the room that we're creating an
+ event builder for
+ key_values (dict): Fields used as the basis of the new event
+
+ Returns:
+ EventBuilder
+ """
+
+ # There's currently only the one event version defined
+ if room_version not in KNOWN_ROOM_VERSIONS:
+ raise Exception(
+ "No event format defined for version %r" % (room_version,)
+ )
+
+ return EventBuilder(
+ store=self.store,
+ state=self.state,
+ auth=self.auth,
+ clock=self.clock,
+ hostname=self.hostname,
+ signing_key=self.signing_key,
+ format_version=room_version_to_event_format(room_version),
+ type=key_values["type"],
+ state_key=key_values.get("state_key"),
+ room_id=key_values["room_id"],
+ sender=key_values["sender"],
+ content=key_values.get("content", {}),
+ unsigned=key_values.get("unsigned", {}),
+ redacts=key_values.get("redacts", None),
+ )
+
+
+def create_local_event_from_event_dict(clock, hostname, signing_key,
+ format_version, event_dict,
+ internal_metadata_dict=None):
+ """Takes a fully formed event dict, ensuring that fields like `origin`
+ and `origin_server_ts` have correct values for a locally produced event,
+ then signs and hashes it.
+
+ Args:
+ clock (Clock)
+ hostname (str)
+ signing_key
+ format_version (int)
+ event_dict (dict)
+ internal_metadata_dict (dict|None)
+
+ Returns:
+ FrozenEvent
+ """
+
+ # There's currently only the one event version defined
+ if format_version not in KNOWN_EVENT_FORMAT_VERSIONS:
+ raise Exception(
+ "No event format defined for version %r" % (format_version,)
+ )
+
+ if internal_metadata_dict is None:
+ internal_metadata_dict = {}
+
+ time_now = int(clock.time_msec())
+
+ if format_version == EventFormatVersions.V1:
+ event_dict["event_id"] = _create_event_id(clock, hostname)
+
+ event_dict["origin"] = hostname
+ event_dict["origin_server_ts"] = time_now
+
+ event_dict.setdefault("unsigned", {})
+ age = event_dict["unsigned"].pop("age", 0)
+ event_dict["unsigned"].setdefault("age_ts", time_now - age)
+
+ event_dict.setdefault("signatures", {})
+
+ add_hashes_and_signatures(
+ event_dict,
+ hostname,
+ signing_key,
+ )
+ return event_type_from_format_version(format_version)(
+ event_dict, internal_metadata_dict=internal_metadata_dict,
+ )
- self.event_id_count = 0
- def create_event_id(self):
- i = str(self.event_id_count)
- self.event_id_count += 1
+# A counter used when generating new event IDs
+_event_id_counter = 0
- local_part = str(int(self.clock.time())) + i + random_string(5)
- e_id = EventID(local_part, self.hostname)
+def _create_event_id(clock, hostname):
+ """Create a new event ID
- return e_id.to_string()
+ Args:
+ clock (Clock)
+ hostname (str): The server name for the event ID
- def new(self, key_values={}):
- key_values["event_id"] = self.create_event_id()
+ Returns:
+ str
+ """
- time_now = int(self.clock.time_msec())
+ global _event_id_counter
- key_values.setdefault("origin", self.hostname)
- key_values.setdefault("origin_server_ts", time_now)
+ i = str(_event_id_counter)
+ _event_id_counter += 1
- key_values.setdefault("unsigned", {})
- age = key_values["unsigned"].pop("age", 0)
- key_values["unsigned"].setdefault("age_ts", time_now - age)
+ local_part = str(int(clock.time())) + i + random_string(5)
- key_values["signatures"] = {}
+ e_id = EventID(local_part, hostname)
- return EventBuilder(key_values=key_values,)
+ return e_id.to_string()
|
