Andrew Thompson Andrew Thompson - 1 month ago 12
Python Question

Dynamic parameters with Python's retry decorator

I'm currently using the python retrying package which contains the

@retry
decorator that has a number of optional parameters. I have these parameters set correctly for our production environment with long enough wait times in between retries (below it's set to 2000 milliseconds) but I would like to set these values differently for unit testing purposes so that execution is very quick.

For example here the wait_fixed time is set to 2000 milliseconds for production but for my unit test that calls
some_function()
I'd like to override the
wait_fixed
parameter to be 1 millisecond so it executes very quickly.

@retry(stop_max_attempt_number=3, wait_fixed=2000)
def some_function(self):
return True


The problem I'm running into is that the decorator is interpreted when the function is defined so as of yet I have not found a way to override the
wait_fixed
parameter from my unit tests.

Answer

main.py

import settings
from retrying import retry


@retry(stop_max_attempt_number=settings.STOP_MAX_ATTEMPT_NUMBER, 
       wait_fixed=settings.WAIT_FIXED)
def some_function(self):
    return True

settings.py

import json


with open('config.json') as jsonf:
    config = json.loads(jsonf.read())

WAIT_FIXED=int(config['WAIT_FIXED'])
STOP_MAX_ATTEMPT_NUMBER=int(config['STOP_MAX_ATTEMPT_NUMBER'])

config.json

{
    "STOP_MAX_ATTEMPT_NUMBER" : "3",
    "WAIT_FIXED" : "2000"
}

Have your test runner put a suitable config.json in place.