Use an existing python decorator with variable parameters

variable-python-decorators.py

#
# pip install tenacity
# Usage:
# → py variable-python-decorators.py 4
# The given maximum attempt number is 4
# We want this function to be retried 5 times
# We want this function to be retried 5 times
# We want this function to be retried 5 times
# We want this function to be retried 5 times
# We want this function to be retried 5 times
# The function was retried 5 times.
# We want this function to be retried only 4 times
# We want this function to be retried only 4 times
# We want this function to be retried only 4 times
# We want this function to be retried only 4 times
# The function was retried 4 times.
# 

import sys
from tenacity import retry, stop_after_attempt

# Typically, if the decorators you use are customisable, you
# have to pass parameters in the decorator like this:
max_attempts = 5
@retry(stop=stop_after_attempt(max_attempts))
def constant_decoration():
    print "We want this function to be retried {} times".format(max_attempts)
    raise Exception("Exception thrown to trigger retry")

def static_decorator():
    try:
        constant_decoration()
    except:
        print "The function was retried {} times.".format(max_attempts)

# To obtain a behavior that is variable based on runtime given arguments
# or maybe configuration, you can enhance the decorator like this:
#
# Create your own decarator that forward the call to the underlying decorator
# with the arguments you want
def variable_retry(func):
    def _retry(*args):
        if args.count > 0:
            def call():
                func(*args)
            variable_max_attempt = int(args[0])
            return apply(retry(stop=stop_after_attempt(variable_max_attempt))(call))
        else:
            return func(*args)
    return _retry

# Use your new decorator
@variable_retry
def variable_decoration(given_max_attempts):
    print "We want this function to be retried only {} times".format(given_max_attempts)
    raise Exception("Exception thrown to trigger retry")

def variable_decorator(given_max_attempts):
    try:
        variable_decoration(given_max_attempts)
    except:
        print "The function was retried {} times.".format(given_max_attempts)

def main(args):
    given_max_attempts = args[1]
    print "The given maximum attempt number is {}".format(given_max_attempts)
    static_decorator()
    variable_decorator(given_max_attempts)

if __name__ == "__main__":
    main(sys.argv)