justbackoff 
A simple backoff algorithm for Python >3.6.
Install
$ pip install justbackoffUsage
Backoff is a counter. It starts at min_ms. After every call to duration(),
it is multiplied by factor. It is capped at max_ms.
It returns to min_ms on every call to reset().
jitter adds randomness (see below).
Simple example
from justbackoff import Backoff
b = Backoff(min_ms=100, max_ms=10000, factor=2, jitter=False)
print(b.duration())
print(b.duration())
print(b.duration())
print("Reset!")
b.reset()
print(b.duration())
0.1
0.2
0.4
Reset!
0.1
Example using socket package
import socket
import time
from justbackoff import Backoff
sock = socket.socket()
b = Backoff()
while True:
try:
sock.connect(("127.0.0.1", 1337))
except Exception as e:
d = b.duration()
print("{}, reconnecting in {} seconds".format(e, d))
time.sleep(d)
continue
b.reset()
sock.send("Hello, world!")
sock.close()
Example using jitter
Enabling jitter adds some randomization to the backoff durations.
See Amazon's writeup of performance gains using jitter.
Seeding is not necessary but doing so gives repeatable results.
import random
from justbackoff import Backoff
b = Backoff(min_ms=100, max_ms=10000, factor=2, jitter=True)
random.seed(42)
print(b.duration())
print(b.duration())
print(b.duration())
print("Reset!")
b.reset()
print(b.duration())
print(b.duration())
print(b.duration())0.1
0.102501075522
0.182508795511
Reset!
0.1
0.173647121416
0.303009846227Credits
Ported from Go backoff
