synapse/tests/api/test_ratelimiting.py
Andrew Morgan f4e6495b5d
Performance improvements and refactor of Ratelimiter (#7595)
While working on https://github.com/matrix-org/synapse/issues/5665 I found myself digging into the `Ratelimiter` class and seeing that it was both:

* Rather undocumented, and
* causing a *lot* of config checks

This PR attempts to refactor and comment the `Ratelimiter` class, as well as encourage config file accesses to only be done at instantiation. 

Best to be reviewed commit-by-commit.
2020-06-05 10:47:20 +01:00

97 lines
3.8 KiB
Python

from synapse.api.ratelimiting import LimitExceededError, Ratelimiter
from tests import unittest
class TestRatelimiter(unittest.TestCase):
def test_allowed_via_can_do_action(self):
limiter = Ratelimiter(clock=None, rate_hz=0.1, burst_count=1)
allowed, time_allowed = limiter.can_do_action(key="test_id", _time_now_s=0)
self.assertTrue(allowed)
self.assertEquals(10.0, time_allowed)
allowed, time_allowed = limiter.can_do_action(key="test_id", _time_now_s=5)
self.assertFalse(allowed)
self.assertEquals(10.0, time_allowed)
allowed, time_allowed = limiter.can_do_action(key="test_id", _time_now_s=10)
self.assertTrue(allowed)
self.assertEquals(20.0, time_allowed)
def test_allowed_via_ratelimit(self):
limiter = Ratelimiter(clock=None, rate_hz=0.1, burst_count=1)
# Shouldn't raise
limiter.ratelimit(key="test_id", _time_now_s=0)
# Should raise
with self.assertRaises(LimitExceededError) as context:
limiter.ratelimit(key="test_id", _time_now_s=5)
self.assertEqual(context.exception.retry_after_ms, 5000)
# Shouldn't raise
limiter.ratelimit(key="test_id", _time_now_s=10)
def test_allowed_via_can_do_action_and_overriding_parameters(self):
"""Test that we can override options of can_do_action that would otherwise fail
an action
"""
# Create a Ratelimiter with a very low allowed rate_hz and burst_count
limiter = Ratelimiter(clock=None, rate_hz=0.1, burst_count=1)
# First attempt should be allowed
allowed, time_allowed = limiter.can_do_action(("test_id",), _time_now_s=0,)
self.assertTrue(allowed)
self.assertEqual(10.0, time_allowed)
# Second attempt, 1s later, will fail
allowed, time_allowed = limiter.can_do_action(("test_id",), _time_now_s=1,)
self.assertFalse(allowed)
self.assertEqual(10.0, time_allowed)
# But, if we allow 10 actions/sec for this request, we should be allowed
# to continue.
allowed, time_allowed = limiter.can_do_action(
("test_id",), _time_now_s=1, rate_hz=10.0
)
self.assertTrue(allowed)
self.assertEqual(1.1, time_allowed)
# Similarly if we allow a burst of 10 actions
allowed, time_allowed = limiter.can_do_action(
("test_id",), _time_now_s=1, burst_count=10
)
self.assertTrue(allowed)
self.assertEqual(1.0, time_allowed)
def test_allowed_via_ratelimit_and_overriding_parameters(self):
"""Test that we can override options of the ratelimit method that would otherwise
fail an action
"""
# Create a Ratelimiter with a very low allowed rate_hz and burst_count
limiter = Ratelimiter(clock=None, rate_hz=0.1, burst_count=1)
# First attempt should be allowed
limiter.ratelimit(key=("test_id",), _time_now_s=0)
# Second attempt, 1s later, will fail
with self.assertRaises(LimitExceededError) as context:
limiter.ratelimit(key=("test_id",), _time_now_s=1)
self.assertEqual(context.exception.retry_after_ms, 9000)
# But, if we allow 10 actions/sec for this request, we should be allowed
# to continue.
limiter.ratelimit(key=("test_id",), _time_now_s=1, rate_hz=10.0)
# Similarly if we allow a burst of 10 actions
limiter.ratelimit(key=("test_id",), _time_now_s=1, burst_count=10)
def test_pruning(self):
limiter = Ratelimiter(clock=None, rate_hz=0.1, burst_count=1)
limiter.can_do_action(key="test_id_1", _time_now_s=0)
self.assertIn("test_id_1", limiter.actions)
limiter.can_do_action(key="test_id_2", _time_now_s=10)
self.assertNotIn("test_id_1", limiter.actions)