Code Snippet — July 31, 2026 Retry with Exponential Backoff, Jitter & C

💻 Code Snippet — July 31, 2026

Retry with Exponential Backoff, Jitter & Circuit Breaker (Python 3.10+)

Zero-dependency @retry decorator for flaky APIs, DB connections, and network calls:

import random, time, functools
from typing import Callable, Type, Optional

def retry(max_attempts=3, base_delay=1.0, max_delay=60.0,
          backoff_factor=2.0, jitter="full",
          retryable_exceptions=(Exception,),
          circuit_breaker=0, circuit_cooldown=30.0,
          max_elapsed=None,
          on_retry=None):
    def decorator(func: Callable) -> Callable:
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            start = time.monotonic()
            for attempt in range(1, max_attempts + 1):
                if max_elapsed and (time.monotonic() - start >= max_elapsed):
                    raise TimeoutError(f"Exceeded max_elapsed={max_elapsed}s")
                try:
                    return func(*args, **kwargs)
                except retryable_exceptions as exc:
                    if attempt == max_attempts:
                        raise
                    delay = min(base_delay * (backoff_factor ** (attempt - 1)), max_delay)
                    if jitter == "full":
                        delay = random.uniform(0, delay)
                    elif jitter == "equal":
                        delay = random.uniform(delay / 2, delay)
                    if on_retry:
                        on_retry(attempt, delay, exc)
                    time.sleep(delay)
        return wrapper
    return decorator

@retry(max_attempts=5, jitter="full", max_elapsed=30)
def call_api():
    ...

Features: Exponential backoff + 3 jitter modes, per-exception policies, circuit breaker, wall-clock deadline, logging hooks. Full version with circuit breaker + per_exception map in today's workspace.

When you can't add tenacity (Lambda cold starts, Dockerfile limits), this gives you production-grade retry logic in one decorator.