gecko-dev/taskcluster/taskgraph/taskgraph.py

72 строки
2.3 KiB
Python

# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
from __future__ import absolute_import, print_function, unicode_literals
from .graph import Graph
from .task import Task
import attr
import six
@attr.s(frozen=True)
class TaskGraph(object):
"""
Representation of a task graph.
A task graph is a combination of a Graph and a dictionary of tasks indexed
by label. TaskGraph instances should be treated as immutable.
"""
tasks = attr.ib()
graph = attr.ib()
def __attrs_post_init__(self):
assert set(self.tasks) == self.graph.nodes
def for_each_task(self, f, *args, **kwargs):
for task_label in self.graph.visit_postorder():
task = self.tasks[task_label]
f(task, self, *args, **kwargs)
def __getitem__(self, label):
"Get a task by label"
return self.tasks[label]
def __contains__(self, label):
return label in self.tasks
def __iter__(self):
"Iterate over tasks in undefined order"
return six.itervalues(self.tasks)
def to_json(self):
"Return a JSON-able object representing the task graph, as documented"
named_links_dict = self.graph.named_links_dict()
# this dictionary may be keyed by label or by taskid, so let's just call it 'key'
tasks = {}
for key in self.graph.visit_postorder():
tasks[key] = self.tasks[key].to_json()
# overwrite dependencies with the information in the taskgraph's edges.
tasks[key]['dependencies'] = named_links_dict.get(key, {})
return tasks
@classmethod
def from_json(cls, tasks_dict):
"""
This code is used to generate the a TaskGraph using a dictionary
which is representative of the TaskGraph.
"""
tasks = {}
edges = set()
for key, value in six.iteritems(tasks_dict):
tasks[key] = Task.from_json(value)
if 'task_id' in value:
tasks[key].task_id = value['task_id']
for depname, dep in six.iteritems(value['dependencies']):
edges.add((key, dep, depname))
task_graph = cls(tasks, Graph(set(tasks), edges))
return tasks, task_graph