retryz 0.1.1

Retry decorator with a bunch of configuration parameters.

Introduction

Function decorator that helps to retry the function under certain criteria.

This package contains the retry decorator and a bunch of configuration parameters for this decorator.

Tested on python 2.7 and python 3.4.

For quick start, check the tutorial section of this page. Check test_retryz.py for detail examples.

Installation

pip install retryz

Tutorial

• Retry if ValueError is caught.

@retry(on_error=ValueError)
def my_func():
    ...

• Retry if ValueError or TypeError is caught.

@retry(on_errors=[ValueError, TypeError])
def my_func():
    ...

• Retry until TypeError is caught.

@retry(unless_error=TypeError)
def my_func():
    ...

• Retry until TypeError or AttributeError is caught.

@retry(unless_errors=[TypeError, AttributeError])
def my_func():
    ...

• When on_error is a callback, it will retry until on_error returns False. Note that callback could be a function or an instancemethod. But it could not be a staticmethod or class method. It takes one parameter which is the error instance raised by the decorated function.

def _error_callback(self, ex):
    assert_that(ex, instance_of(TypeError))
    return self.call_count != 4

@retry(on_error=_error_callback)
def error_call_back(self):
    ...

• Retry if returns certain value.

@retry(on_return=True)
def my_func(self):
    ...

• Retry if return value in the list.

@retry(on_returns=[1, 2, 3, 4, 5])
def my_func(self):
    ...

• Retry until certain value is returned.

@retry(unless_return=4)
def my_func(self):
    ...

• Retry until any of the value is returned.

@retry(unless_returns=[3, 4])
def my_func(self):
    ...

• When on_return is a callback, it will retry until on_return returns False. Note that callback could be a function or an instancemethod. But it could not be a staticmethod or class method. It takes one parameter which is the return value of the decorated function.

def _return_callback(ret):
    return 4 + ret < 7

@retry(on_return=_return_callback)
def my_func(self):
    ...

• Retry until timeout (in seconds)

@retry(timeout=0.1)
def my_func():
    ...

• Retry maximum X times.

@retry(limit=3)
def my_func():
    ...

• Wait X seconds between each retry.

@retry(wait=0.1, timeout=0.3)
def my_func():
    ...

• When wait is a callback, it will wait for the amount of seconds returned by the callback. The callback could be a function or a instance method. It takes one parameter which is the current count of retry.

def _wait_callback(self, tried):
    return 2 ** tried

@retry(wait=_wait_callback, timeout=0.1)
def my_func():
    ...

To file issue, please visit:

https://github.com/jealous/retryz

Contact author:

[e-mail]