def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer):
super().prepare(reactor, clock, hs)
# poke the other server's signing key into the key store, so that we don't
# make requests for it
verify_key = signedjson.key.get_verify_key(
self.OTHER_SERVER_SIGNATURE_KEY)
verify_key_id = "%s:%s" % (verify_key.alg, verify_key.version)
self.get_success(hs.get_datastores().main.store_server_verify_keys(
from_server=self.OTHER_SERVER_NAME,
ts_added_ms=clock.time_msec(),
verify_keys=[(
self.OTHER_SERVER_NAME,
verify_key_id,
FetchKeyResult(
verify_key=verify_key,
valid_until_ts=clock.time_msec() + 1000,
),
)],
))
def create_local_event_from_event_dict(
clock: Clock,
hostname: str,
signing_key: SigningKey,
room_version: RoomVersion,
event_dict: JsonDict,
internal_metadata_dict: Optional[JsonDict] = None,
) -> EventBase:
"""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.
"""
format_version = room_version.event_format
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.setdefault("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(room_version, event_dict, hostname, signing_key)
return make_event_from_dict(event_dict,
room_version,
internal_metadata_dict=internal_metadata_dict)
async def get_retry_limiter(
destination: str,
clock: Clock,
store: DataStore,
ignore_backoff: bool = False,
**kwargs: Any,
) -> "RetryDestinationLimiter":
"""For a given destination check if we have previously failed to
send a request there and are waiting before retrying the destination.
If we are not ready to retry the destination, this will raise a
NotRetryingDestination exception. Otherwise, will return a Context Manager
that will mark the destination as down if an exception is thrown (excluding
CodeMessageException with code < 500)
Args:
destination: name of homeserver
clock: timing source
store: datastore
ignore_backoff: true to ignore the historical backoff data and
try the request anyway. We will still reset the retry_interval on success.
Example usage:
try:
limiter = await get_retry_limiter(destination, clock, store)
with limiter:
response = await do_request()
except NotRetryingDestination:
# We aren't ready to retry that destination.
raise
"""
failure_ts = None
retry_last_ts, retry_interval = (0, 0)
retry_timings = await store.get_destination_retry_timings(destination)
if retry_timings:
failure_ts = retry_timings.failure_ts
retry_last_ts = retry_timings.retry_last_ts
retry_interval = retry_timings.retry_interval
now = int(clock.time_msec())
if not ignore_backoff and retry_last_ts + retry_interval > now:
raise NotRetryingDestination(
retry_last_ts=retry_last_ts,
retry_interval=retry_interval,
destination=destination,
)
# if we are ignoring the backoff data, we should also not increment the backoff
# when we get another failure - otherwise a server can very quickly reach the
# maximum backoff even though it might only have been down briefly
backoff_on_failure = not ignore_backoff
return RetryDestinationLimiter(
destination,
clock,
store,
failure_ts,
retry_interval,
backoff_on_failure=backoff_on_failure,
**kwargs,
)
