fastapi-cb is a Python implementation of the Circuit Breaker pattern,
described in Michael T. Nygard's book Release It!_.
Circuit breakers exist to allow one subsystem to fail without destroying the entire system. This is done by wrapping dangerous operations (typically integration points) with a component that can circumvent calls when the system is not healthy.
This project is a fork of aiobreaker by Alexander Lyon that add support for integration with FastAPI.
- Works well with FastAPI framework
- Configurable list of excluded exceptions (e.g. business exceptions)
- Configurable failure threshold and reset timeout
- Support for several event listeners per circuit breaker
- Can guard generator functions
- Functions and properties for easy monitoring and management
asynciosupport- Optional redis backing
- Synchronous and asynchronous event listeners
All you need is python 3.8 or higher.
To install, simply download from pypi:
pip install fastapi_cbThe first step is to create an instance of CircuitBreaker for each
integration point you want to protect against.
from fastapi_cb import CircuitBreaker
# Used in database integration points
db_breaker = CircuitBreaker(fail_max=5, reset_timeout=timedelta(seconds=60))
@db_breaker
async def outside_integration():
"""Hits the api"""
...At that point, go ahead and get familiar with the documentation.