def periodic(self):
start_time = compat.monotonic()
try:
self.flush()
finally:
self.interval = max(
0,
self._configured_interval - (compat.monotonic() - start_time))
def test_rate_liimter_effective_rate_rates():
limiter = RateLimiter(rate_limit=100)
# Static rate limit window
starting_window = compat.monotonic()
with mock.patch("ddtrace.internal.compat.monotonic") as mock_time:
mock_time.return_value = starting_window
for _ in range(100):
assert limiter.is_allowed() is True
assert limiter.effective_rate == 1.0
assert limiter.current_window == starting_window
for i in range(1, 101):
assert limiter.is_allowed() is False
rate = 100 / (100 + i)
assert limiter.effective_rate == rate
assert limiter.current_window == starting_window
prev_rate = 0.5
with mock.patch("ddtrace.internal.compat.monotonic") as mock_time:
window = starting_window + 1.0
mock_time.return_value = window
for i in range(100):
assert limiter.is_allowed() is True
assert limiter.effective_rate == 0.75
assert limiter.current_window == window
for i in range(1, 101):
assert limiter.is_allowed() is False
rate = 100 / (100 + i)
assert limiter.effective_rate == (rate + prev_rate) / 2
assert limiter.current_window == window
def stop(self):
# type: () -> StopWatch
"""Stops the watch."""
if self._started_at is None:
raise RuntimeError("Can not stop a stopwatch that has not been"
" started")
self._stopped_at = compat.monotonic()
return self
def test_rate_limiter_rate_limit_negative():
limiter = RateLimiter(rate_limit=-1)
assert limiter.rate_limit == -1
assert limiter.tokens == -1
assert limiter.max_tokens == -1
now = compat.monotonic()
with mock.patch("ddtrace.internal.compat.monotonic") as mock_time:
for i in range(10000):
# Make sure the time is different for every check
mock_time.return_value = now + i
assert limiter.is_allowed() is True
def test_rate_limiter_is_allowed_small_gaps():
limiter = RateLimiter(rate_limit=100)
# Start time
now = compat.monotonic()
gap = 1.0 / 100.0
# Keep incrementing by a gap to keep us at our rate limit
with mock.patch("ddtrace.internal.compat.monotonic") as mock_time:
for i in range(10000):
# Keep the same timeframe
mock_time.return_value = now + (gap * i)
assert limiter.is_allowed() is True
def test_rate_limiter_effective_rate_starting_rate():
limiter = RateLimiter(rate_limit=1)
now = compat.monotonic()
with mock.patch("ddtrace.internal.compat.monotonic") as mock_time:
mock_time.return_value = now
# Default values
assert limiter.current_window == 0
assert limiter.prev_window_rate is None
# Accessing the effective rate doesn't change anything
assert limiter.effective_rate == 1.0
assert limiter.current_window == 0
assert limiter.prev_window_rate is None
# Calling `.is_allowed()` updates the values
assert limiter.is_allowed() is True
assert limiter.effective_rate == 1.0
assert limiter.current_window == now
assert limiter.prev_window_rate is None
# Gap of 0.9999 seconds, same window
mock_time.return_value = now + 0.9999
assert limiter.is_allowed() is False
# DEV: We have rate_limit=1 set
assert limiter.effective_rate == 0.5
assert limiter.current_window == now
assert limiter.prev_window_rate is None
# Gap of 1.0 seconds, new window
mock_time.return_value = now + 1.0
assert limiter.is_allowed() is True
assert limiter.effective_rate == 0.75
assert limiter.current_window == (now + 1.0)
assert limiter.prev_window_rate == 0.5
# Gap of 1.9999 seconds, same window
mock_time.return_value = now + 1.9999
assert limiter.is_allowed() is False
assert limiter.effective_rate == 0.5
assert limiter.current_window == (now + 1.0) # Same as old window
assert limiter.prev_window_rate == 0.5
# Large gap of 100 seconds, new window
mock_time.return_value = now + 100.0
assert limiter.is_allowed() is True
assert limiter.effective_rate == 0.75
assert limiter.current_window == (now + 100.0)
assert limiter.prev_window_rate == 0.5
def elapsed(self):
# type: () -> float
"""Get how many seconds have elapsed.
:return: Number of seconds elapsed
:rtype: float
"""
# NOTE: datetime.timedelta does not support nanoseconds, so keep a float here
if self._started_at is None:
raise RuntimeError("Can not get the elapsed time of a stopwatch"
" if it has not been started/stopped")
if self._stopped_at is None:
now = compat.monotonic()
else:
now = self._stopped_at
return now - self._started_at
def test_rate_limiter_is_allowed_large_gap():
limiter = RateLimiter(rate_limit=100)
# Start time
now = compat.monotonic()
with mock.patch("ddtrace.internal.compat.monotonic") as mock_time:
# Keep the same timeframe
mock_time.return_value = now
for _ in range(100):
assert limiter.is_allowed() is True
# Large gap before next call to `is_allowed()`
with mock.patch("ddtrace.internal.compat.monotonic") as mock_time:
mock_time.return_value = now + 100
for _ in range(100):
assert limiter.is_allowed() is True
def test_rate_limiter_is_allowed(rate_limit):
limiter = RateLimiter(rate_limit=rate_limit)
def check_limit():
# Up to the allowed limit is allowed
for _ in range(rate_limit):
assert limiter.is_allowed() is True
# Any over the limit is disallowed
for _ in range(1000):
assert limiter.is_allowed() is False
# Start time
now = compat.monotonic()
# Check the limit for 5 time frames
for i in range(5):
with mock.patch("ddtrace.internal.compat.monotonic") as mock_time:
# Keep the same timeframe
mock_time.return_value = now + i
check_limit()
def start(self):
# type: () -> StopWatch
"""Starts the watch."""
self._started_at = compat.monotonic()
return self
def test_rate_limiter_init():
limiter = RateLimiter(rate_limit=100)
assert limiter.rate_limit == 100
assert limiter.tokens == 100
assert limiter.max_tokens == 100
assert limiter.last_update <= compat.monotonic()