Files
deb-python-taskflow/taskflow/engines/action_engine/actions/retry.py
Min Pae 7f0c457e72 Map optional arguments as well as required arguments
Optional arguments that are not explicitly required are being ignored
when arguments are being mapped based on inference from atoms' execute
method signatures.  This patch adds support for mapping optional
arguments in addition to required arguments.

Change-Id: I440c02dcd901a563df512e33754b13e3c05d4155
2015-02-10 22:32:38 -08:00

134 lines
4.7 KiB
Python

# -*- coding: utf-8 -*-
# Copyright (C) 2012-2013 Yahoo! Inc. All Rights Reserved.
#
# 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.
from taskflow.engines.action_engine.actions import base
from taskflow.engines.action_engine import executor as ex
from taskflow import logging
from taskflow import retry as retry_atom
from taskflow import states
from taskflow.types import failure
from taskflow.types import futures
LOG = logging.getLogger(__name__)
def _execute_retry(retry, arguments):
try:
result = retry.execute(**arguments)
except Exception:
result = failure.Failure()
return (ex.EXECUTED, result)
def _revert_retry(retry, arguments):
try:
result = retry.revert(**arguments)
except Exception:
result = failure.Failure()
return (ex.REVERTED, result)
class RetryAction(base.Action):
"""An action that handles executing, state changes, ... of retry atoms."""
def __init__(self, storage, notifier, walker_factory):
super(RetryAction, self).__init__(storage, notifier, walker_factory)
self._executor = futures.SynchronousExecutor()
@staticmethod
def handles(atom):
return isinstance(atom, retry_atom.Retry)
def _get_retry_args(self, retry, addons=None):
scope_walker = self._walker_factory(retry)
arguments = self._storage.fetch_mapped_args(
retry.rebind,
atom_name=retry.name,
scope_walker=scope_walker,
optional_args=retry.optional
)
history = self._storage.get_retry_history(retry.name)
arguments[retry_atom.EXECUTE_REVERT_HISTORY] = history
if addons:
arguments.update(addons)
return arguments
def change_state(self, retry, state, result=base.NO_RESULT):
old_state = self._storage.get_atom_state(retry.name)
if state in base.SAVE_RESULT_STATES:
save_result = None
if result is not base.NO_RESULT:
save_result = result
self._storage.save(retry.name, save_result, state)
elif state == states.REVERTED:
self._storage.cleanup_retry_history(retry.name, state)
else:
if state == old_state:
# NOTE(imelnikov): nothing really changed, so we should not
# write anything to storage and run notifications
return
self._storage.set_atom_state(retry.name, state)
retry_uuid = self._storage.get_atom_uuid(retry.name)
details = {
'retry_name': retry.name,
'retry_uuid': retry_uuid,
'old_state': old_state,
}
if result is not base.NO_RESULT:
details['result'] = result
self._notifier.notify(state, details)
def execute(self, retry):
def _on_done_callback(fut):
result = fut.result()[-1]
if isinstance(result, failure.Failure):
self.change_state(retry, states.FAILURE, result=result)
else:
self.change_state(retry, states.SUCCESS, result=result)
self.change_state(retry, states.RUNNING)
fut = self._executor.submit(_execute_retry, retry,
self._get_retry_args(retry))
fut.add_done_callback(_on_done_callback)
fut.atom = retry
return fut
def revert(self, retry):
def _on_done_callback(fut):
result = fut.result()[-1]
if isinstance(result, failure.Failure):
self.change_state(retry, states.FAILURE)
else:
self.change_state(retry, states.REVERTED)
self.change_state(retry, states.REVERTING)
arg_addons = {
retry_atom.REVERT_FLOW_FAILURES: self._storage.get_failures(),
}
fut = self._executor.submit(_revert_retry, retry,
self._get_retry_args(retry,
addons=arg_addons))
fut.add_done_callback(_on_done_callback)
fut.atom = retry
return fut
def on_failure(self, retry, atom, last_failure):
self._storage.save_retry_failure(retry.name, atom.name, last_failure)
arguments = self._get_retry_args(retry)
return retry.on_failure(**arguments)