80e1aadc49
Update all .py source files by
$ pyupgrade --py3-only $(git ls-files | grep ".py$")
to modernize the code according to Python 3 syntaxes.
pep8 errors are fixed by
$ autopep8 --select=E127,E128,E501 --max-line-length 79 -r \
--in-place taskflow
Also add the pyupgrade hook to pre-commit to avoid merging additional
Python 2 syntaxes.
Change-Id: Ifd0a0ade9789497482c7937bffd82c48acfb3d78
75 lines
2.6 KiB
Python
75 lines
2.6 KiB
Python
# Copyright (C) 2012 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 import flow
|
|
from taskflow.types import graph as gr
|
|
|
|
|
|
class Flow(flow.Flow):
|
|
"""Linear flow pattern.
|
|
|
|
A linear (potentially nested) flow of *tasks/flows* that can be
|
|
applied in order as one unit and rolled back as one unit using
|
|
the reverse order that the *tasks/flows* have been applied in.
|
|
"""
|
|
|
|
_no_last_item = object()
|
|
"""Sentinel object used to denote no last item has been assigned.
|
|
|
|
This is used to track no last item being added, since at creation there
|
|
is no last item, but since the :meth:`.add` routine can take any object
|
|
including none, we have to use a different object to be able to
|
|
distinguish the lack of any last item...
|
|
"""
|
|
|
|
def __init__(self, name, retry=None):
|
|
super().__init__(name, retry)
|
|
self._graph = gr.OrderedDiGraph(name=name)
|
|
self._last_item = self._no_last_item
|
|
|
|
def add(self, *items):
|
|
"""Adds a given task/tasks/flow/flows to this flow."""
|
|
for item in items:
|
|
if not self._graph.has_node(item):
|
|
self._graph.add_node(item)
|
|
if self._last_item is not self._no_last_item:
|
|
self._graph.add_edge(self._last_item, item,
|
|
attr_dict={flow.LINK_INVARIANT: True})
|
|
self._last_item = item
|
|
return self
|
|
|
|
def __len__(self):
|
|
return len(self._graph)
|
|
|
|
def __iter__(self):
|
|
yield from self._graph.nodes
|
|
|
|
@property
|
|
def requires(self):
|
|
requires = set()
|
|
prior_provides = set()
|
|
if self._retry is not None:
|
|
requires.update(self._retry.requires)
|
|
prior_provides.update(self._retry.provides)
|
|
for item in self:
|
|
requires.update(item.requires - prior_provides)
|
|
prior_provides.update(item.provides)
|
|
return frozenset(requires)
|
|
|
|
def iter_nodes(self):
|
|
yield from self._graph.nodes(data=True)
|
|
|
|
def iter_links(self):
|
|
yield from self._graph.edges(data=True)
|