retry之python重试机制

安装 pip install retry

Retry装饰器

retry(exceptions=Exception, tries=-1, delay=0, max_delay=None, backoff=1, jitter=0, logger=logging_logger):

"""Return a retry decorator.

 

    :param exceptions: an exception or a tuple of exceptions to catch. default: Exception.

    :param tries: the maximum number of attempts. default: -1 (infinite).

    :param delay: initial delay between attempts. default: 0.

    :param max_delay: the maximum value of delay. default: None (no limit).

    :param backoff: multiplier applied to delay between attempts. default: 1 (no backoff).

    :param jitter: extra seconds added to delay between attempts. default: 0.

                   fixed if a number, random if a range tuple (min, max)

    :param logger: logger.warning(fmt, error, delay) will be called on failed attempts.

                   default: retry.logging_logger. if None, logging is disabled.

    """

使用

@retry(ZeroDivisionError, tries=3, delay=2)

def make_trouble():

retry_call

def retry_call(f, fargs=None, fkwargs=None, exceptions=Exception, tries=-1, delay=0, max_delay=None, backoff=1,

jitter=0,

logger=logging_logger):

"""

    Calls a function and re-executes it if it failed.

 

    :param f: the function to execute.

    :param fargs: the positional arguments of the function to execute.

    :param fkwargs: the named arguments of the function to execute.

    :param exceptions: an exception or a tuple of exceptions to catch. default: Exception.

    :param tries: the maximum number of attempts. default: -1 (infinite).

    :param delay: initial delay between attempts. default: 0.

    :param max_delay: the maximum value of delay. default: None (no limit).

    :param backoff: multiplier applied to delay between attempts. default: 1 (no backoff).

    :param jitter: extra seconds added to delay between attempts. default: 0.

                   fixed if a number, random if a range tuple (min, max)

    :param logger: logger.warning(fmt, error, delay) will be called on failed attempts.

                   default: retry.logging_logger. if None, logging is disabled.

    :returns: the result of the f function.

    """

该方法和retry装饰器类似，除了它带函数和函数的参数，他可以动态的判断重试次数

import requests

from retry.api import retry_call

def make_trouble(service, info=None):

if not info:

info = ''

r = requests.get(service + info)

return r.text

def what_is_my_ip(approach=None):

if approach == "optimistic":

tries = 1

elif approach == "conservative":

tries = 3

else:

# skeptical

tries = -1

result = retry_call(make_trouble, fargs=["http://ipinfo.io/"], fkwargs={"info": "ip"}, tries=tries)

print(result)

what_is_my_ip("conservative")