sagah
Orchestrated, async sagas in Python
Table of Contents:
Installation
sagah requires Python 3.6 or above.
pip install sagahGuide
Example usage:
from sagah import Saga
state = {"counter": 0}
def incr():
state["counter"] += 1
def decr():
state["counter"] -= 1
with Saga() as saga:
await saga.action(incr, decr)
await saga.action(incr, decr)
assert state["counter"] == 2If some action fails, the compensating functions from previous transactions will be called to restore the state:
from sagah import Saga
state = {"counter": 0}
def incr():
state["counter"] += 1
def decr():
state["counter"] -= 1
def fail():
raise ValueError("oops")
try:
with Saga() as saga:
await saga.action(incr, decr)
await saga.action(incr, decr)
await saga.action(fail, noop)
except Exception:
assert state["counter"] == 0Development
To develop sagah, install dependencies and enable the pre-commit hook:
pip install pre-commit poetry
poetry install
pre-commit installTo run tests:
poetry run pytest
