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Diffstat (limited to 'lib/ansible/module_utils/cloud.py')
| -rw-r--r-- | lib/ansible/module_utils/cloud.py | 217 |
1 files changed, 0 insertions, 217 deletions
diff --git a/lib/ansible/module_utils/cloud.py b/lib/ansible/module_utils/cloud.py deleted file mode 100644 index 0d29071fe1..0000000000 --- a/lib/ansible/module_utils/cloud.py +++ /dev/null @@ -1,217 +0,0 @@ -# -# (c) 2016 Allen Sanabria, <asanabria@linuxdynasty.org> -# -# This file is part of Ansible -# -# Ansible is free software: you can redistribute it and/or modify -# it under the terms of the GNU General Public License as published by -# the Free Software Foundation, either version 3 of the License, or -# (at your option) any later version. -# -# Ansible is distributed in the hope that it will be useful, -# but WITHOUT ANY WARRANTY; without even the implied warranty of -# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -# GNU General Public License for more details. -# -# You should have received a copy of the GNU General Public License -# along with Ansible. If not, see <http://www.gnu.org/licenses/>. -# -""" -This module adds shared support for generic cloud modules - -In order to use this module, include it as part of a custom -module as shown below. - -from ansible.module_utils.cloud import CloudRetry - -The 'cloud' module provides the following common classes: - - * CloudRetry - - The base class to be used by other cloud providers, in order to - provide a backoff/retry decorator based on status codes. - - - Example using the AWSRetry class which inherits from CloudRetry. - - @AWSRetry.exponential_backoff(retries=10, delay=3) - get_ec2_security_group_ids_from_names() - - @AWSRetry.jittered_backoff() - get_ec2_security_group_ids_from_names() - -""" -import random -from functools import wraps -import syslog -import time - - -def _exponential_backoff(retries=10, delay=2, backoff=2, max_delay=60): - """ Customizable exponential backoff strategy. - Args: - retries (int): Maximum number of times to retry a request. - delay (float): Initial (base) delay. - backoff (float): base of the exponent to use for exponential - backoff. - max_delay (int): Optional. If provided each delay generated is capped - at this amount. Defaults to 60 seconds. - Returns: - Callable that returns a generator. This generator yields durations in - seconds to be used as delays for an exponential backoff strategy. - Usage: - >>> backoff = _exponential_backoff() - >>> backoff - <function backoff_backoff at 0x7f0d939facf8> - >>> list(backoff()) - [2, 4, 8, 16, 32, 60, 60, 60, 60, 60] - """ - def backoff_gen(): - for retry in range(0, retries): - sleep = delay * backoff ** retry - yield sleep if max_delay is None else min(sleep, max_delay) - return backoff_gen - - -def _full_jitter_backoff(retries=10, delay=3, max_delay=60, _random=random): - """ Implements the "Full Jitter" backoff strategy described here - https://www.awsarchitectureblog.com/2015/03/backoff.html - Args: - retries (int): Maximum number of times to retry a request. - delay (float): Approximate number of seconds to sleep for the first - retry. - max_delay (int): The maximum number of seconds to sleep for any retry. - _random (random.Random or None): Makes this generator testable by - allowing developers to explicitly pass in the a seeded Random. - Returns: - Callable that returns a generator. This generator yields durations in - seconds to be used as delays for a full jitter backoff strategy. - Usage: - >>> backoff = _full_jitter_backoff(retries=5) - >>> backoff - <function backoff_backoff at 0x7f0d939facf8> - >>> list(backoff()) - [3, 6, 5, 23, 38] - >>> list(backoff()) - [2, 1, 6, 6, 31] - """ - def backoff_gen(): - for retry in range(0, retries): - yield _random.randint(0, min(max_delay, delay * 2 ** retry)) - return backoff_gen - - -class CloudRetry(object): - """ CloudRetry can be used by any cloud provider, in order to implement a - backoff algorithm/retry effect based on Status Code from Exceptions. - """ - # This is the base class of the exception. - # AWS Example botocore.exceptions.ClientError - base_class = None - - @staticmethod - def status_code_from_exception(error): - """ Return the status code from the exception object - Args: - error (object): The exception itself. - """ - pass - - @staticmethod - def found(response_code, catch_extra_error_codes=None): - """ Return True if the Response Code to retry on was found. - Args: - response_code (str): This is the Response Code that is being matched against. - """ - pass - - @classmethod - def _backoff(cls, backoff_strategy, catch_extra_error_codes=None): - """ Retry calling the Cloud decorated function using the provided - backoff strategy. - Args: - backoff_strategy (callable): Callable that returns a generator. The - generator should yield sleep times for each retry of the decorated - function. - """ - def deco(f): - @wraps(f) - def retry_func(*args, **kwargs): - for delay in backoff_strategy(): - try: - return f(*args, **kwargs) - except Exception as e: - if isinstance(e, cls.base_class): - response_code = cls.status_code_from_exception(e) - if cls.found(response_code, catch_extra_error_codes): - msg = "{0}: Retrying in {1} seconds...".format(str(e), delay) - syslog.syslog(syslog.LOG_INFO, msg) - time.sleep(delay) - else: - # Return original exception if exception is not a ClientError - raise e - else: - # Return original exception if exception is not a ClientError - raise e - return f(*args, **kwargs) - - return retry_func # true decorator - - return deco - - @classmethod - def exponential_backoff(cls, retries=10, delay=3, backoff=2, max_delay=60, catch_extra_error_codes=None): - """ - Retry calling the Cloud decorated function using an exponential backoff. - - Kwargs: - retries (int): Number of times to retry a failed request before giving up - default=10 - delay (int or float): Initial delay between retries in seconds - default=3 - backoff (int or float): backoff multiplier e.g. value of 2 will - double the delay each retry - default=1.1 - max_delay (int or None): maximum amount of time to wait between retries. - default=60 - """ - return cls._backoff(_exponential_backoff( - retries=retries, delay=delay, backoff=backoff, max_delay=max_delay), catch_extra_error_codes) - - @classmethod - def jittered_backoff(cls, retries=10, delay=3, max_delay=60, catch_extra_error_codes=None): - """ - Retry calling the Cloud decorated function using a jittered backoff - strategy. More on this strategy here: - - https://www.awsarchitectureblog.com/2015/03/backoff.html - - Kwargs: - retries (int): Number of times to retry a failed request before giving up - default=10 - delay (int): Initial delay between retries in seconds - default=3 - max_delay (int): maximum amount of time to wait between retries. - default=60 - """ - return cls._backoff(_full_jitter_backoff( - retries=retries, delay=delay, max_delay=max_delay), catch_extra_error_codes) - - @classmethod - def backoff(cls, tries=10, delay=3, backoff=1.1, catch_extra_error_codes=None): - """ - Retry calling the Cloud decorated function using an exponential backoff. - - Compatibility for the original implementation of CloudRetry.backoff that - did not provide configurable backoff strategies. Developers should use - CloudRetry.exponential_backoff instead. - - Kwargs: - tries (int): Number of times to try (not retry) before giving up - default=10 - delay (int or float): Initial delay between retries in seconds - default=3 - backoff (int or float): backoff multiplier e.g. value of 2 will - double the delay each retry - default=1.1 - """ - return cls.exponential_backoff( - retries=tries - 1, delay=delay, backoff=backoff, max_delay=None, catch_extra_error_codes=catch_extra_error_codes) |