/usr/lib/python2.7/dist-packages/mrjob/retry.py is in python-mrjob 0.3.3.2-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 | # Copyright 2009-2010 Yelp
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""A simple wrapper for retrying when we get transient errors."""
import logging
import time
log = logging.getLogger('mrjob.retry')
class RetryWrapper(object):
"""This class can wrap any object. The wrapped object will behave like
the original one, except that if you call a function and it raises a
retriable exception, we'll back off for a certain number of seconds
and call the function again, until it succeeds or we get a non-retriable
exception.
"""
def __init__(self, wrapped, retry_if, backoff=15, multiplier=1.5,
max_tries=10):
"""
Wrap the given object
:param wrapped: the object to wrap. this should work for functions as
well as regular objects (essentially, we're wrapping
``__call__``)
:param retry_if: a method that takes an exception, and returns whether
we should retry
:type backoff: float
:param backoff: the number of seconds to wait the first time we get a
retriable error.
:type multiplier: float
:param multiplier: if we retry multiple times, the amount to multiply
the backoff time by every time we get an error
:type max_tries: int
:param max_tries: how many tries we get. ``0`` means to keep trying
forever
"""
self.__wrapped = wrapped
self.__retry_if = retry_if
self.__backoff = backoff
if self.__backoff <= 0:
raise ValueError('backoff must be positive')
self.__multiplier = multiplier
if self.__multiplier < 1:
raise ValueError('multiplier must be at least one!')
self.__max_tries = max_tries
def __getattr__(self, name):
"""The glue that makes functions retriable, and returns other
attributes from the wrapped object as-is."""
x = getattr(self.__wrapped, name)
if hasattr(x, '__call__'):
return self.__wrap_method_with_call_and_maybe_retry(x)
else:
return x
def __wrap_method_with_call_and_maybe_retry(self, f):
"""Wrap method f in a retry loop."""
def call_and_maybe_retry(*args, **kwargs):
backoff = self.__backoff
tries = 0
while (not self.__max_tries or tries < self.__max_tries):
try:
return f(*args, **kwargs)
except Exception, ex:
if self.__retry_if(ex):
log.info('Got retriable error: %r' % ex)
log.info('Backing off for %.1f seconds' % backoff)
time.sleep(backoff)
tries += 1
backoff *= self.__multiplier
else:
raise
# pretend to be the original function
call_and_maybe_retry.__name__ == f.__name__
return call_and_maybe_retry
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