59 lines
2.0 KiB
Python
59 lines
2.0 KiB
Python
# Licensed under the Apache License, Version 2.0 (the "License"); you may
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# not use this file except in compliance with the License. You may obtain
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# a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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# License for the specific language governing permissions and limitations
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# under the License.
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#
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"""Utilities and helper functions."""
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from oslo_log import log as logging
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import retrying
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import six
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from os_brick.i18n import _
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LOG = logging.getLogger(__name__)
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def retry(exceptions, interval=1, retries=3, backoff_rate=2):
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def _retry_on_exception(e):
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return isinstance(e, exceptions)
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def _backoff_sleep(previous_attempt_number, delay_since_first_attempt_ms):
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exp = backoff_rate ** previous_attempt_number
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wait_for = max(0, interval * exp)
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LOG.debug("Sleeping for %s seconds", wait_for)
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return wait_for * 1000.0
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def _print_stop(previous_attempt_number, delay_since_first_attempt_ms):
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delay_since_first_attempt = delay_since_first_attempt_ms / 1000.0
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LOG.debug("Failed attempt %s", previous_attempt_number)
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LOG.debug("Have been at this for %s seconds",
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delay_since_first_attempt)
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return previous_attempt_number == retries
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if retries < 1:
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raise ValueError(_('Retries must be greater than or '
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'equal to 1 (received: %s). ') % retries)
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def _decorator(f):
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@six.wraps(f)
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def _wrapper(*args, **kwargs):
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r = retrying.Retrying(retry_on_exception=_retry_on_exception,
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wait_func=_backoff_sleep,
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stop_func=_print_stop)
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return r.call(f, *args, **kwargs)
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return _wrapper
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return _decorator
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