Reference library

Reliability & rate limiting

Retries, exponential backoff, circuit breakers, token buckets, and idempotent handlers.

4 matches

GCRA generic cell rate algorithm in Python

Mock implementation of the Generic Cell Rate Algorithm (GCRA) for traffic shaping and rate limiting.

from collections import deque
import time

class GCRA:
    def __init__(self, rate, burst):
        self.tau = burst
        self.T = rate
        self.t = 0
        self.LCT = 0

    def add_cell(self, arrival_time):
        if arrival_time <= self.t:
            return False
        arrived_early = (arrival_time - s…

14 0 Open

Reliability & rate limiting easy

How to Inject Random Latency for Chaos Testing in Python

Mock unreliable services by wrapping functions with a decorator that adds random network-like delays before execution.

chaos-engineering decorators latency

Python

import random
import time
from functools import wraps

def inject_latency(func):
    @wraps(func)
    def wrapper(*args, **kwargs):
        latency = random.uniform(0.1, 0.5)
        print(f"Injecting {latency:.3f}s latency...")
        time.sleep(latency)
        return func(*args, **kwargs)
    return wrapper

@inje…

12 0 Open

Reliability & rate limiting easy

How to Mock a Timeout per HTTP Request in Python

Simulate a per-request HTTP timeout using unittest.mock to test timeout handling without network access.

mocking timeout testing

Python

import time
from unittest.mock import Mock, patch

# Simulate an HTTP client that might time out
def fetch_data(url, timeout=5):
    time.sleep(0.5)  # Simulate network delay
    return f"Response from {url}"

# Mock to test timeout behavior without real network
def test_timeout():
    mock_response = Mock(side_effect…

12 0 Open

Reliability & rate limiting medium

Leaky Bucket Rate Limiter in Python: Smooth Burst Traffic

Implements a token-bucket-style leaky bucket rate limiter that smooths bursty traffic by draining at a fixed rate and dropping excess packets.

rate-limiting traffic-shaping simulation

Python

import time
import random


class LeakyBucket:
    def __init__(self, capacity, drain_rate):
        self.capacity = capacity
        self.drain_rate = drain_rate
        self.water = 0.0
        self.last_time = time.time()

    def allow(self, packet_size=1.0):
        now = time.time()
        elapsed = now - self.…

14 0 Open

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