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Diffstat (limited to 'taskcluster/taskgraph/task/base.py')
-rw-r--r-- | taskcluster/taskgraph/task/base.py | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/taskcluster/taskgraph/task/base.py b/taskcluster/taskgraph/task/base.py new file mode 100644 index 0000000000..2d9cbf5d95 --- /dev/null +++ b/taskcluster/taskgraph/task/base.py @@ -0,0 +1,108 @@ +# 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 + +import abc + + +class Task(object): + """ + Representation of a task in a TaskGraph. Each Task has, at creation: + + - kind: the name of the task kind + - label; the label for this task + - attributes: a dictionary of attributes for this task (used for filtering) + - task: the task definition (JSON-able dictionary) + + And later, as the task-graph processing proceeds: + + - task_id -- TaskCluster taskId under which this task will be created + - optimized -- true if this task need not be performed + + A kind represents a collection of tasks that share common characteristics. + For example, all build jobs. Each instance of a kind is intialized with a + path from which it draws its task configuration. The instance is free to + store as much local state as it needs. + """ + __metaclass__ = abc.ABCMeta + + def __init__(self, kind, label, attributes, task): + self.kind = kind + self.label = label + self.attributes = attributes + self.task = task + + self.task_id = None + self.optimized = False + + self.attributes['kind'] = kind + + def __eq__(self, other): + return self.kind == other.kind and \ + self.label == other.label and \ + self.attributes == other.attributes and \ + self.task == other.task and \ + self.task_id == other.task_id + + @classmethod + @abc.abstractmethod + def load_tasks(cls, kind, path, config, parameters, loaded_tasks): + """ + Load the tasks for a given kind. + + The `kind` is the name of the kind; the configuration for that kind + named this class. + + The `path` is the path to the configuration directory for the kind. This + can be used to load extra data, templates, etc. + + The `parameters` give details on which to base the task generation. + See `taskcluster/docs/parameters.rst` for details. + + At the time this method is called, all kinds on which this kind depends + (that is, specified in the `kind-dependencies` key in `self.config` + have already loaded their tasks, and those tasks are available in + the list `loaded_tasks`. + + The return value is a list of Task instances. + """ + + @abc.abstractmethod + def get_dependencies(self, taskgraph): + """ + Get the set of task labels this task depends on, by querying the full + task set, given as `taskgraph`. + + Returns a list of (task_label, dependency_name) pairs describing the + dependencies. + """ + + def optimize(self, params): + """ + Determine whether this task can be optimized, and if it can, what taskId + it should be replaced with. + + The return value is a tuple `(optimized, taskId)`. If `optimized` is + true, then the task will be optimized (in other words, not included in + the task graph). If the second argument is a taskid, then any + dependencies on this task will isntead depend on that taskId. It is an + error to return no taskId for a task on which other tasks depend. + + The default never optimizes. + """ + return False, None + + @classmethod + def from_json(cls, task_dict): + """ + Given a data structure as produced by taskgraph.to_json, re-construct + the original Task object. This is used to "resume" the task-graph + generation process, for example in Action tasks. + """ + return cls( + kind=task_dict['attributes']['kind'], + label=task_dict['label'], + attributes=task_dict['attributes'], + task=task_dict['task']) |