# -*- coding: utf-8 -*-
# Copyright (C) 2012 Yahoo! Inc. All Rights Reserved.
# Copyright (C) 2013 Rackspace Hosting 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.
import abc
import copy
import os
from oslo_utils import timeutils
from oslo_utils import uuidutils
import six
from taskflow import exceptions as exc
from taskflow import states
from taskflow.types import failure as ft
from taskflow.utils import misc
# Internal helpers...
def _format_meta(metadata, indent):
"""Format the common metadata dictionary in the same manner."""
if not metadata:
return []
lines = [
'%s- metadata:' % (" " * indent),
]
for (k, v) in metadata.items():
# Progress for now is a special snowflake and will be formatted
# in percent format.
if k == 'progress' and isinstance(v, misc.NUMERIC_TYPES):
v = "%0.2f%%" % (v * 100.0)
lines.append("%s+ %s = %s" % (" " * (indent + 2), k, v))
return lines
def _format_shared(obj, indent):
"""Format the common shared attributes in the same manner."""
if obj is None:
return []
lines = []
for attr_name in ("uuid", "state"):
if not hasattr(obj, attr_name):
continue
lines.append("%s- %s = %s" % (" " * indent, attr_name,
getattr(obj, attr_name)))
return lines
def _is_all_none(arg, *args):
if arg is not None:
return False
for more_arg in args:
if more_arg is not None:
return False
return True
def _copy_function(deep_copy):
if deep_copy:
return copy.deepcopy
else:
return lambda x: x
def _safe_marshal_time(when):
if not when:
return None
return timeutils.marshall_now(now=when)
def _safe_unmarshal_time(when):
if not when:
return None
return timeutils.unmarshall_time(when)
def _fix_meta(data):
# Handle the case where older schemas allowed this to be non-dict by
# correcting this case by replacing it with a dictionary when a non-dict
# is found.
meta = data.get('meta')
if not isinstance(meta, dict):
meta = {}
return meta
[docs]class LogBook(object):
"""A collection of flow details and associated metadata.
Typically this class contains a collection of flow detail entries
for a given engine (or job) so that those entities can track what 'work'
has been completed for resumption, reverting and miscellaneous tracking
purposes.
The data contained within this class need **not** be persisted to the
backend storage in real time. The data in this class will only be
guaranteed to be persisted when a save occurs via some backend
connection.
NOTE(harlowja): the naming of this class is analogous to a ship's log or a
similar type of record used in detailing work that has been completed (or
work that has not been completed).
:ivar created_at: A ``datetime.datetime`` object of when this logbook
was created.
:ivar updated_at: A ``datetime.datetime`` object of when this logbook
was last updated at.
:ivar meta: A dictionary of meta-data associated with this logbook.
"""
def __init__(self, name, uuid=None):
if uuid:
self._uuid = uuid
else:
self._uuid = uuidutils.generate_uuid()
self._name = name
self._flowdetails_by_id = {}
self.created_at = timeutils.utcnow()
self.updated_at = None
self.meta = {}
[docs] def add(self, fd):
"""Adds a new flow detail into this logbook.
NOTE(harlowja): if an existing flow detail exists with the same
uuid the existing one will be overwritten with the newly provided
one.
Does not *guarantee* that the details will be immediately saved.
"""
self._flowdetails_by_id[fd.uuid] = fd
self.updated_at = timeutils.utcnow()
[docs] def find(self, flow_uuid):
"""Locate the flow detail corresponding to the given uuid.
:returns: the flow detail with that uuid
:rtype: :py:class:`.FlowDetail` (or ``None`` if not found)
"""
return self._flowdetails_by_id.get(flow_uuid, None)
[docs] def merge(self, lb, deep_copy=False):
"""Merges the current object state with the given ones state.
If ``deep_copy`` is provided as truthy then the
local object will use ``copy.deepcopy`` to replace this objects
local attributes with the provided objects attributes (**only** if
there is a difference between this objects attributes and the
provided attributes). If ``deep_copy`` is falsey (the default) then a
reference copy will occur instead when a difference is detected.
NOTE(harlowja): If the provided object is this object itself
then **no** merging is done. Also note that this does **not** merge
the flow details contained in either.
:returns: this logbook (freshly merged with the incoming object)
:rtype: :py:class:`.LogBook`
"""
if lb is self:
return self
copy_fn = _copy_function(deep_copy)
if self.meta != lb.meta:
self.meta = copy_fn(lb.meta)
if lb.created_at != self.created_at:
self.created_at = copy_fn(lb.created_at)
if lb.updated_at != self.updated_at:
self.updated_at = copy_fn(lb.updated_at)
return self
[docs] def to_dict(self, marshal_time=False):
"""Translates the internal state of this object to a ``dict``.
NOTE(harlowja): The returned ``dict`` does **not** include any
contained flow details.
:returns: this logbook in ``dict`` form
"""
if not marshal_time:
marshal_fn = lambda x: x
else:
marshal_fn = _safe_marshal_time
return {
'name': self.name,
'meta': self.meta,
'uuid': self.uuid,
'updated_at': marshal_fn(self.updated_at),
'created_at': marshal_fn(self.created_at),
}
[docs] @classmethod
def from_dict(cls, data, unmarshal_time=False):
"""Translates the given ``dict`` into an instance of this class.
NOTE(harlowja): the ``dict`` provided should come from a prior
call to :meth:`.to_dict`.
:returns: a new logbook
:rtype: :py:class:`.LogBook`
"""
if not unmarshal_time:
unmarshal_fn = lambda x: x
else:
unmarshal_fn = _safe_unmarshal_time
obj = cls(data['name'], uuid=data['uuid'])
obj.updated_at = unmarshal_fn(data['updated_at'])
obj.created_at = unmarshal_fn(data['created_at'])
obj.meta = _fix_meta(data)
return obj
@property
def uuid(self):
"""The unique identifer of this logbook."""
return self._uuid
@property
def name(self):
"""The name of this logbook."""
return self._name
def __iter__(self):
for fd in six.itervalues(self._flowdetails_by_id):
yield fd
def __len__(self):
return len(self._flowdetails_by_id)
[docs] def copy(self, retain_contents=True):
"""Copies this logbook.
Creates a shallow copy of this logbook. If this logbook contains
flow details and ``retain_contents`` is truthy (the default) then
the flow details container will be shallow copied (the flow details
contained there-in will **not** be copied). If ``retain_contents`` is
falsey then the copied logbook will have **no** contained flow
details (but it will have the rest of the local objects attributes
copied).
:returns: a new logbook
:rtype: :py:class:`.LogBook`
"""
clone = copy.copy(self)
if not retain_contents:
clone._flowdetails_by_id = {}
else:
clone._flowdetails_by_id = self._flowdetails_by_id.copy()
if self.meta:
clone.meta = self.meta.copy()
return clone
[docs]class FlowDetail(object):
"""A collection of atom details and associated metadata.
Typically this class contains a collection of atom detail entries that
represent the atoms in a given flow structure (along with any other needed
metadata relevant to that flow).
The data contained within this class need **not** be persisted to the
backend storage in real time. The data in this class will only be
guaranteed to be persisted when a save (or update) occurs via some backend
connection.
:ivar meta: A dictionary of meta-data associated with this flow detail.
"""
def __init__(self, name, uuid):
self._uuid = uuid
self._name = name
self._atomdetails_by_id = {}
# TODO(bnemec): This should be documented as an ivar, but can't be due
# to https://github.com/sphinx-doc/sphinx/issues/2549
#: The state of the flow associated with this flow detail.
self.state = None
self.meta = {}
[docs] def update(self, fd):
"""Updates the objects state to be the same as the given one.
This will assign the private and public attributes of the given
flow detail directly to this object (replacing any existing
attributes in this object; even if they are the **same**).
NOTE(harlowja): If the provided object is this object itself
then **no** update is done.
:returns: this flow detail
:rtype: :py:class:`.FlowDetail`
"""
if fd is self:
return self
self._atomdetails_by_id = fd._atomdetails_by_id
self.state = fd.state
self.meta = fd.meta
return self
[docs] def merge(self, fd, deep_copy=False):
"""Merges the current object state with the given one's state.
If ``deep_copy`` is provided as truthy then the
local object will use ``copy.deepcopy`` to replace this objects
local attributes with the provided objects attributes (**only** if
there is a difference between this objects attributes and the
provided attributes). If ``deep_copy`` is falsey (the default) then a
reference copy will occur instead when a difference is detected.
NOTE(harlowja): If the provided object is this object itself
then **no** merging is done. Also this does **not** merge the atom
details contained in either.
:returns: this flow detail (freshly merged with the incoming object)
:rtype: :py:class:`.FlowDetail`
"""
if fd is self:
return self
copy_fn = _copy_function(deep_copy)
if self.meta != fd.meta:
self.meta = copy_fn(fd.meta)
if self.state != fd.state:
# NOTE(imelnikov): states are just strings, no need to copy.
self.state = fd.state
return self
[docs] def copy(self, retain_contents=True):
"""Copies this flow detail.
Creates a shallow copy of this flow detail. If this detail contains
flow details and ``retain_contents`` is truthy (the default) then
the atom details container will be shallow copied (the atom details
contained there-in will **not** be copied). If ``retain_contents`` is
falsey then the copied flow detail will have **no** contained atom
details (but it will have the rest of the local objects attributes
copied).
:returns: a new flow detail
:rtype: :py:class:`.FlowDetail`
"""
clone = copy.copy(self)
if not retain_contents:
clone._atomdetails_by_id = {}
else:
clone._atomdetails_by_id = self._atomdetails_by_id.copy()
if self.meta:
clone.meta = self.meta.copy()
return clone
[docs] def to_dict(self):
"""Translates the internal state of this object to a ``dict``.
NOTE(harlowja): The returned ``dict`` does **not** include any
contained atom details.
:returns: this flow detail in ``dict`` form
"""
return {
'name': self.name,
'meta': self.meta,
'state': self.state,
'uuid': self.uuid,
}
[docs] @classmethod
def from_dict(cls, data):
"""Translates the given ``dict`` into an instance of this class.
NOTE(harlowja): the ``dict`` provided should come from a prior
call to :meth:`.to_dict`.
:returns: a new flow detail
:rtype: :py:class:`.FlowDetail`
"""
obj = cls(data['name'], data['uuid'])
obj.state = data.get('state')
obj.meta = _fix_meta(data)
return obj
[docs] def add(self, ad):
"""Adds a new atom detail into this flow detail.
NOTE(harlowja): if an existing atom detail exists with the same
uuid the existing one will be overwritten with the newly provided
one.
Does not *guarantee* that the details will be immediately saved.
"""
self._atomdetails_by_id[ad.uuid] = ad
[docs] def find(self, ad_uuid):
"""Locate the atom detail corresponding to the given uuid.
:returns: the atom detail with that uuid
:rtype: :py:class:`.AtomDetail` (or ``None`` if not found)
"""
return self._atomdetails_by_id.get(ad_uuid)
@property
def uuid(self):
"""The unique identifer of this flow detail."""
return self._uuid
@property
def name(self):
"""The name of this flow detail."""
return self._name
def __iter__(self):
for ad in six.itervalues(self._atomdetails_by_id):
yield ad
def __len__(self):
return len(self._atomdetails_by_id)
[docs]@six.add_metaclass(abc.ABCMeta)
class AtomDetail(object):
"""A collection of atom specific runtime information and metadata.
This is a base **abstract** class that contains attributes that are used
to connect a atom to the persistence layer before, during, or after it is
running. It includes any results it may have produced, any state that it
may be in (for example ``FAILURE``), any exception that occurred when
running, and any associated stacktrace that may have occurring during an
exception being thrown. It may also contain any other metadata that
should also be stored along-side the details about the connected atom.
The data contained within this class need **not** be persisted to the
backend storage in real time. The data in this class will only be
guaranteed to be persisted when a save (or update) occurs via some backend
connection.
:ivar intention: The execution strategy of the atom associated
with this atom detail (used by an engine/others to
determine if the associated atom needs to be
executed, reverted, retried and so-on).
:ivar meta: A dictionary of meta-data associated with this atom detail.
:ivar version: A version tuple or string that represents the
atom version this atom detail is associated with (typically
used for introspection and any data migration
strategies).
:ivar results: Any results the atom produced from either its
``execute`` method or from other sources.
:ivar revert_results: Any results the atom produced from either its
``revert`` method or from other sources.
:ivar AtomDetail.failure: If the atom failed (due to its ``execute`` method
raising) this will be a
:py:class:`~taskflow.types.failure.Failure` object that
represents that failure (if there was no failure this
will be set to none).
:ivar revert_failure: If the atom failed (possibly due to its ``revert``
method raising) this will be a
:py:class:`~taskflow.types.failure.Failure` object
that represents that failure (if there was no
failure this will be set to none).
"""
def __init__(self, name, uuid):
self._uuid = uuid
self._name = name
# TODO(bnemec): This should be documented as an ivar, but can't be due
# to https://github.com/sphinx-doc/sphinx/issues/2549
#: The state of the atom associated with this atom detail.
self.state = None
self.intention = states.EXECUTE
self.results = None
self.failure = None
self.revert_results = None
self.revert_failure = None
self.meta = {}
self.version = None
@property
def last_results(self):
"""Gets the atoms last result.
If the atom has produced many results (for example if it has been
retried, reverted, executed and ...) this returns the last one of
many results.
"""
return self.results
[docs] def update(self, ad):
"""Updates the object's state to be the same as the given one.
This will assign the private and public attributes of the given
atom detail directly to this object (replacing any existing
attributes in this object; even if they are the **same**).
NOTE(harlowja): If the provided object is this object itself
then **no** update is done.
:returns: this atom detail
:rtype: :py:class:`.AtomDetail`
"""
if ad is self:
return self
self.state = ad.state
self.intention = ad.intention
self.meta = ad.meta
self.failure = ad.failure
self.results = ad.results
self.revert_results = ad.revert_results
self.revert_failure = ad.revert_failure
self.version = ad.version
return self
[docs] @abc.abstractmethod
def merge(self, other, deep_copy=False):
"""Merges the current object state with the given ones state.
If ``deep_copy`` is provided as truthy then the
local object will use ``copy.deepcopy`` to replace this objects
local attributes with the provided objects attributes (**only** if
there is a difference between this objects attributes and the
provided attributes). If ``deep_copy`` is falsey (the default) then a
reference copy will occur instead when a difference is detected.
NOTE(harlowja): If the provided object is this object itself
then **no** merging is done. Do note that **no** results are merged
in this method. That operation **must** to be the responsibilty of
subclasses to implement and override this abstract method
and provide that merging themselves as they see fit.
:returns: this atom detail (freshly merged with the incoming object)
:rtype: :py:class:`.AtomDetail`
"""
copy_fn = _copy_function(deep_copy)
# NOTE(imelnikov): states and intentions are just strings,
# so there is no need to copy them (strings are immutable in python).
self.state = other.state
self.intention = other.intention
if self.failure != other.failure:
# NOTE(imelnikov): we can't just deep copy Failures, as they
# contain tracebacks, which are not copyable.
if other.failure:
if deep_copy:
self.failure = other.failure.copy()
else:
self.failure = other.failure
else:
self.failure = None
if self.revert_failure != other.revert_failure:
# NOTE(imelnikov): we can't just deep copy Failures, as they
# contain tracebacks, which are not copyable.
if other.revert_failure:
if deep_copy:
self.revert_failure = other.revert_failure.copy()
else:
self.revert_failure = other.revert_failure
else:
self.revert_failure = None
if self.meta != other.meta:
self.meta = copy_fn(other.meta)
if self.version != other.version:
self.version = copy_fn(other.version)
return self
[docs] @abc.abstractmethod
def put(self, state, result):
"""Puts a result (acquired in the given state) into this detail."""
[docs] def to_dict(self):
"""Translates the internal state of this object to a ``dict``.
:returns: this atom detail in ``dict`` form
"""
if self.failure:
failure = self.failure.to_dict()
else:
failure = None
if self.revert_failure:
revert_failure = self.revert_failure.to_dict()
else:
revert_failure = None
return {
'failure': failure,
'revert_failure': revert_failure,
'meta': self.meta,
'name': self.name,
'results': self.results,
'revert_results': self.revert_results,
'state': self.state,
'version': self.version,
'intention': self.intention,
'uuid': self.uuid,
}
[docs] @classmethod
def from_dict(cls, data):
"""Translates the given ``dict`` into an instance of this class.
NOTE(harlowja): the ``dict`` provided should come from a prior
call to :meth:`.to_dict`.
:returns: a new atom detail
:rtype: :py:class:`.AtomDetail`
"""
obj = cls(data['name'], data['uuid'])
obj.state = data.get('state')
obj.intention = data.get('intention')
obj.results = data.get('results')
obj.revert_results = data.get('revert_results')
obj.version = data.get('version')
obj.meta = _fix_meta(data)
failure = data.get('failure')
if failure:
obj.failure = ft.Failure.from_dict(failure)
revert_failure = data.get('revert_failure')
if revert_failure:
obj.revert_failure = ft.Failure.from_dict(revert_failure)
return obj
@property
def uuid(self):
"""The unique identifer of this atom detail."""
return self._uuid
@property
def name(self):
"""The name of this atom detail."""
return self._name
[docs] @abc.abstractmethod
def reset(self, state):
"""Resets this atom detail and sets ``state`` attribute value."""
[docs] @abc.abstractmethod
def copy(self):
"""Copies this atom detail."""
[docs]class TaskDetail(AtomDetail):
"""A task detail (an atom detail typically associated with a |tt| atom).
.. |tt| replace:: :py:class:`~taskflow.task.Task`
"""
[docs] def reset(self, state):
"""Resets this task detail and sets ``state`` attribute value.
This sets any previously set ``results``, ``failure``,
and ``revert_results`` attributes back to ``None`` and sets the
state to the provided one, as well as setting this task
details ``intention`` attribute to ``EXECUTE``.
"""
self.results = None
self.failure = None
self.revert_results = None
self.revert_failure = None
self.state = state
self.intention = states.EXECUTE
[docs] def put(self, state, result):
"""Puts a result (acquired in the given state) into this detail.
Returns whether this object was modified (or whether it was not).
"""
was_altered = False
if state != self.state:
self.state = state
was_altered = True
if state == states.REVERT_FAILURE:
if self.revert_failure != result:
self.revert_failure = result
was_altered = True
if not _is_all_none(self.results, self.revert_results):
self.results = None
self.revert_results = None
was_altered = True
elif state == states.FAILURE:
if self.failure != result:
self.failure = result
was_altered = True
if not _is_all_none(self.results, self.revert_results,
self.revert_failure):
self.results = None
self.revert_results = None
self.revert_failure = None
was_altered = True
elif state == states.SUCCESS:
if not _is_all_none(self.revert_results, self.revert_failure,
self.failure):
self.revert_results = None
self.revert_failure = None
self.failure = None
was_altered = True
# We don't really have the ability to determine equality of
# task (user) results at the current time, without making
# potentially bad guesses, so assume the task detail always needs
# to be saved if they are not exactly equivalent...
if result is not self.results:
self.results = result
was_altered = True
elif state == states.REVERTED:
if not _is_all_none(self.revert_failure):
self.revert_failure = None
was_altered = True
if result is not self.revert_results:
self.revert_results = result
was_altered = True
return was_altered
[docs] def merge(self, other, deep_copy=False):
"""Merges the current task detail with the given one.
NOTE(harlowja): This merge does **not** copy and replace
the ``results`` or ``revert_results`` if it differs. Instead the
current objects ``results`` and ``revert_results`` attributes directly
becomes (via assignment) the other objects attributes. Also note that
if the provided object is this object itself then **no** merging is
done.
See: https://bugs.launchpad.net/taskflow/+bug/1452978 for
what happens if this is copied at a deeper level (for example by
using ``copy.deepcopy`` or by using ``copy.copy``).
:returns: this task detail (freshly merged with the incoming object)
:rtype: :py:class:`.TaskDetail`
"""
if not isinstance(other, TaskDetail):
raise exc.NotImplementedError("Can only merge with other"
" task details")
if other is self:
return self
super(TaskDetail, self).merge(other, deep_copy=deep_copy)
self.results = other.results
self.revert_results = other.revert_results
return self
[docs] def copy(self):
"""Copies this task detail.
Creates a shallow copy of this task detail (any meta-data and
version information that this object maintains is shallow
copied via ``copy.copy``).
NOTE(harlowja): This copy does **not** copy and replace
the ``results`` or ``revert_results`` attribute if it differs. Instead
the current objects ``results`` and ``revert_results`` attributes
directly becomes (via assignment) the cloned objects attributes.
See: https://bugs.launchpad.net/taskflow/+bug/1452978 for
what happens if this is copied at a deeper level (for example by
using ``copy.deepcopy`` or by using ``copy.copy``).
:returns: a new task detail
:rtype: :py:class:`.TaskDetail`
"""
clone = copy.copy(self)
clone.results = self.results
clone.revert_results = self.revert_results
if self.meta:
clone.meta = self.meta.copy()
if self.version:
clone.version = copy.copy(self.version)
return clone
[docs]class RetryDetail(AtomDetail):
"""A retry detail (an atom detail typically associated with a |rt| atom).
.. |rt| replace:: :py:class:`~taskflow.retry.Retry`
"""
def __init__(self, name, uuid):
super(RetryDetail, self).__init__(name, uuid)
self.results = []
[docs] def reset(self, state):
"""Resets this retry detail and sets ``state`` attribute value.
This sets any previously added ``results`` back to an empty list
and resets the ``failure`` and ``revert_failure`` and
``revert_results`` attributes back to ``None`` and sets the state
to the provided one, as well as setting this retry
details ``intention`` attribute to ``EXECUTE``.
"""
self.results = []
self.revert_results = None
self.failure = None
self.revert_failure = None
self.state = state
self.intention = states.EXECUTE
[docs] def copy(self):
"""Copies this retry detail.
Creates a shallow copy of this retry detail (any meta-data and
version information that this object maintains is shallow
copied via ``copy.copy``).
NOTE(harlowja): This copy does **not** copy
the incoming objects ``results`` or ``revert_results`` attributes.
Instead this objects ``results`` attribute list is iterated over and
a new list is constructed with each ``(data, failures)`` element in
that list having its ``failures`` (a dictionary of each named
:py:class:`~taskflow.types.failure.Failure` object that
occured) copied but its ``data`` is left untouched. After
this is done that new list becomes (via assignment) the cloned
objects ``results`` attribute. The ``revert_results`` is directly
assigned to the cloned objects ``revert_results`` attribute.
See: https://bugs.launchpad.net/taskflow/+bug/1452978 for
what happens if the ``data`` in ``results`` is copied at a
deeper level (for example by using ``copy.deepcopy`` or by
using ``copy.copy``).
:returns: a new retry detail
:rtype: :py:class:`.RetryDetail`
"""
clone = copy.copy(self)
results = []
# NOTE(imelnikov): we can't just deep copy Failures, as they
# contain tracebacks, which are not copyable.
for (data, failures) in self.results:
copied_failures = {}
for (key, failure) in six.iteritems(failures):
copied_failures[key] = failure
results.append((data, copied_failures))
clone.results = results
clone.revert_results = self.revert_results
if self.meta:
clone.meta = self.meta.copy()
if self.version:
clone.version = copy.copy(self.version)
return clone
@property
def last_results(self):
"""The last result that was produced."""
try:
return self.results[-1][0]
except IndexError:
exc.raise_with_cause(exc.NotFound, "Last results not found")
@property
def last_failures(self):
"""The last failure dictionary that was produced.
NOTE(harlowja): This is **not** the same as the
local ``failure`` attribute as the obtained failure dictionary in
the ``results`` attribute (which is what this returns) is from
associated atom failures (which is different from the directly
related failure of the retry unit associated with this
atom detail).
"""
try:
return self.results[-1][1]
except IndexError:
exc.raise_with_cause(exc.NotFound, "Last failures not found")
[docs] def put(self, state, result):
"""Puts a result (acquired in the given state) into this detail.
Returns whether this object was modified (or whether it was not).
"""
# Do not clean retry history (only on reset does this happen).
was_altered = False
if state != self.state:
self.state = state
was_altered = True
if state == states.REVERT_FAILURE:
if result != self.revert_failure:
self.revert_failure = result
was_altered = True
if not _is_all_none(self.revert_results):
self.revert_results = None
was_altered = True
elif state == states.FAILURE:
if result != self.failure:
self.failure = result
was_altered = True
if not _is_all_none(self.revert_results, self.revert_failure):
self.revert_results = None
self.revert_failure = None
was_altered = True
elif state == states.SUCCESS:
if not _is_all_none(self.failure, self.revert_failure,
self.revert_results):
self.failure = None
self.revert_failure = None
self.revert_results = None
# Track what we produced, so that we can examine it (or avoid
# using it again).
self.results.append((result, {}))
was_altered = True
elif state == states.REVERTED:
# We don't really have the ability to determine equality of
# task (user) results at the current time, without making
# potentially bad guesses, so assume the retry detail always needs
# to be saved if they are not exactly equivalent...
if result is not self.revert_results:
self.revert_results = result
was_altered = True
if not _is_all_none(self.revert_failure):
self.revert_failure = None
was_altered = True
return was_altered
[docs] @classmethod
def from_dict(cls, data):
"""Translates the given ``dict`` into an instance of this class."""
def decode_results(results):
if not results:
return []
new_results = []
for (data, failures) in results:
new_failures = {}
for (key, data) in six.iteritems(failures):
new_failures[key] = ft.Failure.from_dict(data)
new_results.append((data, new_failures))
return new_results
obj = super(RetryDetail, cls).from_dict(data)
obj.results = decode_results(obj.results)
return obj
[docs] def to_dict(self):
"""Translates the internal state of this object to a ``dict``."""
def encode_results(results):
if not results:
return []
new_results = []
for (data, failures) in results:
new_failures = {}
for (key, failure) in six.iteritems(failures):
new_failures[key] = failure.to_dict()
new_results.append((data, new_failures))
return new_results
base = super(RetryDetail, self).to_dict()
base['results'] = encode_results(base.get('results'))
return base
[docs] def merge(self, other, deep_copy=False):
"""Merges the current retry detail with the given one.
NOTE(harlowja): This merge does **not** deep copy
the incoming objects ``results`` attribute (if it differs). Instead
the incoming objects ``results`` attribute list is **always** iterated
over and a new list is constructed with
each ``(data, failures)`` element in that list having
its ``failures`` (a dictionary of each named
:py:class:`~taskflow.types.failure.Failure` objects that
occurred) copied but its ``data`` is left untouched. After
this is done that new list becomes (via assignment) this
objects ``results`` attribute. Also note that if the provided object
is this object itself then **no** merging is done.
See: https://bugs.launchpad.net/taskflow/+bug/1452978 for
what happens if the ``data`` in ``results`` is copied at a
deeper level (for example by using ``copy.deepcopy`` or by
using ``copy.copy``).
:returns: this retry detail (freshly merged with the incoming object)
:rtype: :py:class:`.RetryDetail`
"""
if not isinstance(other, RetryDetail):
raise exc.NotImplementedError("Can only merge with other"
" retry details")
if other is self:
return self
super(RetryDetail, self).merge(other, deep_copy=deep_copy)
results = []
# NOTE(imelnikov): we can't just deep copy Failures, as they
# contain tracebacks, which are not copyable.
for (data, failures) in other.results:
copied_failures = {}
for (key, failure) in six.iteritems(failures):
if deep_copy:
copied_failures[key] = failure.copy()
else:
copied_failures[key] = failure
results.append((data, copied_failures))
self.results = results
return self
_DETAIL_TO_NAME = {
RetryDetail: 'RETRY_DETAIL',
TaskDetail: 'TASK_DETAIL',
}
_NAME_TO_DETAIL = dict((name, cls)
for (cls, name) in six.iteritems(_DETAIL_TO_NAME))
ATOM_TYPES = list(six.iterkeys(_NAME_TO_DETAIL))
def atom_detail_class(atom_type):
try:
return _NAME_TO_DETAIL[atom_type]
except KeyError:
raise TypeError("Unknown atom type '%s'" % (atom_type))
def atom_detail_type(atom_detail):
try:
return _DETAIL_TO_NAME[type(atom_detail)]
except KeyError:
raise TypeError("Unknown atom '%s' (%s)"
% (atom_detail, type(atom_detail)))
