stamina

Production-grade Retries Made Easy

Transient failures are common in distributed systems. To make your systems resilient, you need to retry failed operations. But bad retries can make things much worse.

stamina is an opinionated wrapper around the great-but-unopinionated Tenacity package. Its goal is to be as ergonomic as possible, while doing the right thing by default, while minimizing potential for misuse. It is the result of years of copy-pasting the same configuration over and over again:

• Retry only on certain exceptions.
• Exponential backoff with jitter between retries.
• Limit the number of retries and total time.
• Automatic async support.
• Preserve type hints of the decorated callable.
• Count (Prometheus) and log (structlog) retries with basic metadata, if they're installed.
• Easy global deactivation for testing.

For example:

import httpx

import stamina


@stamina.retry(on=httpx.HTTPError, attempts=3)
def do_it(code: int) -> httpx.Response:
    resp = httpx.get(f"https://httpbin.org/status/{code}")
    resp.raise_for_status()

    return resp

Async callables work use the same API and it's possible to retry arbitrary blocks, too. Please refer to our tutorial for more examples.

Project Information

• PyPI
• Source Code
• Documentation
• Changelog

Credits

stamina is written by Hynek Schlawack and distributed under the terms of the MIT license.

The development is kindly supported by my employer Variomedia AG and all my amazing GitHub Sponsors.

This project would not be possible without the years of incredible work that went into Tenacity.