Check whether to ratelimit sooner to avoid work

This commit is contained in:
Erik Johnston 2016-10-19 10:45:24 +01:00
parent 50ac1d843d
commit 550308c7a1
2 changed files with 22 additions and 6 deletions

View File

@ -23,7 +23,7 @@ class Ratelimiter(object):
def __init__(self):
self.message_counts = collections.OrderedDict()
def send_message(self, user_id, time_now_s, msg_rate_hz, burst_count):
def send_message(self, user_id, time_now_s, msg_rate_hz, burst_count, update=True):
"""Can the user send a message?
Args:
user_id: The user sending a message.
@ -32,12 +32,15 @@ class Ratelimiter(object):
second.
burst_count: How many messages the user can send before being
limited.
update (bool): Whether to update the message rates or not. This is
useful to check if a message would be allowed to be sent before
its ready to be actually sent.
Returns:
A pair of a bool indicating if they can send a message now and a
time in seconds of when they can next send a message.
"""
self.prune_message_counts(time_now_s)
message_count, time_start, _ignored = self.message_counts.pop(
message_count, time_start, _ignored = self.message_counts.get(
user_id, (0., time_now_s, None),
)
time_delta = time_now_s - time_start
@ -52,6 +55,7 @@ class Ratelimiter(object):
allowed = True
message_count += 1
if update:
self.message_counts[user_id] = (
message_count, time_start, msg_rate_hz
)

View File

@ -16,7 +16,7 @@
from twisted.internet import defer
from synapse.api.constants import EventTypes, Membership
from synapse.api.errors import AuthError, Codes, SynapseError
from synapse.api.errors import AuthError, Codes, SynapseError, LimitExceededError
from synapse.crypto.event_signing import add_hashes_and_signatures
from synapse.events.utils import serialize_event
from synapse.events.validator import EventValidator
@ -239,6 +239,18 @@ class MessageHandler(BaseHandler):
"Tried to send member event through non-member codepath"
)
time_now = self.clock.time()
allowed, time_allowed = self.ratelimiter.send_message(
event.sender, time_now,
msg_rate_hz=self.hs.config.rc_messages_per_second,
burst_count=self.hs.config.rc_message_burst_count,
update=False,
)
if not allowed:
raise LimitExceededError(
retry_after_ms=int(1000 * (time_allowed - time_now)),
)
user = UserID.from_string(event.sender)
assert self.hs.is_mine(user), "User must be our own: %s" % (user,)