#!/usr/bin/env python3
# Copyright 2014-2018 PUNCH Cyber Analytics Group
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from functools import wraps
import threading
import time
# Based on code from https://gist.github.com/gregburek/1441055
def ratelimited():
"""
Thread safe decorator to rate limit a function
"""
lock = threading.Lock()
def decorator(func):
last_call = time.perf_counter()
@wraps(func)
async def ratelimit(*args, **kwargs):
limit = kwargs.get("ratelimit", None)
if limit:
count, seconds = limit.split("/")
interval = int(seconds) / int(count)
lock.acquire()
nonlocal last_call
elapsed = time.perf_counter() - last_call
left_to_wait = interval - elapsed
if left_to_wait > 0:
time.sleep(left_to_wait)
last_call = time.perf_counter()
lock.release()
try:
kwargs.pop("ratelimit")
except KeyError:
pass
return await func(*args, **kwargs)
return ratelimit
return decorator
