1 files changed, 130 insertions, 0 deletions
diff --git a/taskcluster/taskgraph/task/docker_image.py b/taskcluster/taskgraph/task/docker_image.py
new file mode 100644
index 000000000..fd67c4832
--- /dev/null
+++ b/taskcluster/taskgraph/task/docker_image.py
@@ -0,0 +1,130 @@
+# 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 logging
+import json
+import os
+import urllib2
+
+from . import base
+from taskgraph.util.docker import (
+    docker_image,
+    generate_context_hash,
+    INDEX_PREFIX,
+)
+from taskgraph.util.templates import Templates
+
+logger = logging.getLogger(__name__)
+GECKO = os.path.realpath(os.path.join(__file__, '..', '..', '..', '..'))
+ARTIFACT_URL = 'https://queue.taskcluster.net/v1/task/{}/artifacts/{}'
+INDEX_URL = 'https://index.taskcluster.net/v1/task/{}'
+
+
+class DockerImageTask(base.Task):
+
+    def __init__(self, *args, **kwargs):
+        self.index_paths = kwargs.pop('index_paths')
+        super(DockerImageTask, self).__init__(*args, **kwargs)
+
+    def __eq__(self, other):
+        return super(DockerImageTask, self).__eq__(other) and \
+               self.index_paths == other.index_paths
+
+    @classmethod
+    def load_tasks(cls, kind, path, config, params, loaded_tasks):
+        parameters = {
+            'pushlog_id': params.get('pushlog_id', 0),
+            'pushdate': params['moz_build_date'],
+            'pushtime': params['moz_build_date'][8:],
+            'year': params['moz_build_date'][0:4],
+            'month': params['moz_build_date'][4:6],
+            'day': params['moz_build_date'][6:8],
+            'project': params['project'],
+            'docker_image': docker_image,
+            'base_repository': params['base_repository'] or params['head_repository'],
+            'head_repository': params['head_repository'],
+            'head_ref': params['head_ref'] or params['head_rev'],
+            'head_rev': params['head_rev'],
+            'owner': params['owner'],
+            'level': params['level'],
+            'source': '{repo}file/{rev}/taskcluster/ci/docker-image/image.yml'
+                      .format(repo=params['head_repository'], rev=params['head_rev']),
+            'index_image_prefix': INDEX_PREFIX,
+            'artifact_path': 'public/image.tar.zst',
+        }
+
+        tasks = []
+        templates = Templates(path)
+        for image_name, image_symbol in config['images'].iteritems():
+            context_path = os.path.join('testing', 'docker', image_name)
+            context_hash = generate_context_hash(GECKO, context_path, image_name)
+
+            image_parameters = dict(parameters)
+            image_parameters['image_name'] = image_name
+            image_parameters['context_hash'] = context_hash
+
+            image_task = templates.load('image.yml', image_parameters)
+            attributes = {'image_name': image_name}
+
+            # unique symbol for different docker image
+            if 'extra' in image_task['task']:
+                image_task['task']['extra']['treeherder']['symbol'] = image_symbol
+
+            # As an optimization, if the context hash exists for a high level, that image
+            # task ID will be used.  The reasoning behind this is that eventually everything ends
+            # up on level 3 at some point if most tasks use this as a common image
+            # for a given context hash, a worker within Taskcluster does not need to contain
+            # the same image per branch.
+            index_paths = ['{}.level-{}.{}.hash.{}'.format(
+                                INDEX_PREFIX, level, image_name, context_hash)
+                           for level in range(int(params['level']), 4)]
+
+            tasks.append(cls(kind, 'build-docker-image-' + image_name,
+                             task=image_task['task'], attributes=attributes,
+                             index_paths=index_paths))
+
+        return tasks
+
+    def get_dependencies(self, taskgraph):
+        return []
+
+    def optimize(self, params):
+        for index_path in self.index_paths:
+            try:
+                url = INDEX_URL.format(index_path)
+                existing_task = json.load(urllib2.urlopen(url))
+                # Only return the task ID if the artifact exists for the indexed
+                # task.  Otherwise, continue on looking at each of the branches.  Method
+                # continues trying other branches in case mozilla-central has an expired
+                # artifact, but 'project' might not. Only return no task ID if all
+                # branches have been tried
+                request = urllib2.Request(
+                    ARTIFACT_URL.format(existing_task['taskId'], 'public/image.tar.zst'))
+                request.get_method = lambda: 'HEAD'
+                urllib2.urlopen(request)
+
+                # HEAD success on the artifact is enough
+                return True, existing_task['taskId']
+            except urllib2.HTTPError:
+                pass
+
+        return False, None
+
+    @classmethod
+    def from_json(cls, task_dict):
+        # Generating index_paths for optimization
+        imgMeta = task_dict['task']['extra']['imageMeta']
+        image_name = imgMeta['imageName']
+        context_hash = imgMeta['contextHash']
+        index_paths = ['{}.level-{}.{}.hash.{}'.format(
+                            INDEX_PREFIX, level, image_name, context_hash)
+                       for level in range(int(imgMeta['level']), 4)]
+        docker_image_task = cls(kind='docker-image',
+                                label=task_dict['label'],
+                                attributes=task_dict['attributes'],
+                                task=task_dict['task'],
+                                index_paths=index_paths)
+        return docker_image_task