BuildBucket-based build triggering

scripts/master/buildbucket/trigger.py

Index: scripts/master/buildbucket/trigger.py
diff --git a/scripts/master/buildbucket/trigger.py b/scripts/master/buildbucket/trigger.py
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+# Copyright 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Build triggering via buildbucket."""
+
+import json
+
+from twisted.internet import defer
+
+from . import client
+from . import common
+
+
+class TriggeringService(object):
+  """Schedules new builds on buildbucket."""
+
+  def __init__(self, active_master, buildbucket_service):
+    self.active_master = active_master
+    self.buildbucket_service = buildbucket_service
+
+  @classmethod
+  @defer.inlineCallbacks
+  def create(cls, active_master):
+    buildbucket_service = yield client.create_buildbucket_service(active_master)
+    defer.returnValue(cls(active_master, buildbucket_service))
+
+  def start(self):
+    self.buildbucket_service.start()
+
+  def stop(self):
+    self.buildbucket_service.stop()
+
+  @staticmethod
+  def get_buildset(build_def):
+    tags = build_def.get('tags', [])
+    PREFIX = 'buildset:'
+    for t in tags:
+      if t.startswith(PREFIX):
+        return t[len(PREFIX):]
+    return None
+
+  def get_build_url(self, build_id):
+    return 'https://%s/b/%s' % (
+        client.get_default_buildbucket_hostname(self.active_master), build_id)
+
+  @defer.inlineCallbacks
+  def trigger(
+      self, source_build, bucket_name, builder_name, properties, changes=None):
+    """Schedules a build on buildbucket."""
+    info = source_build.getProperties().getProperty(common.INFO_PROPERTY) or {}
+    build_def = info.get(common.BUILD_PROPERTY) or {}
+    bucket_name = bucket_name or build_def.get('bucket')
+    if not bucket_name:
+      # This function should not be called in this case.
+      raise common.Error(
+          'Neither bucket_name is specified, nor the build is from buildbucket')
+
+    tags = []
+    if build_def:
+      tags.append('parent_build_id:%s' % build_def['id'])
+      buildset = self.get_buildset(build_def)
+      if buildset:
+        tags.append('buildset:%s' % buildset)
+
+    response = yield self.buildbucket_service.api.put(body={
+        'bucket': bucket_name,
+        'tags': tags,
+        'parameters_json': json.dumps({
+            'builder_name': builder_name,
+            'properties': properties,
+            'changes': changes or [],
+        }),
+    })
+    result = {
+        'response': response,
+    }
+    build_id = response.get('build', {}).get('id', {})
+    if build_id:
+      result['build_url'] = self.get_build_url(build_id)
+    defer.returnValue(result)
+
+
+_master_triggering_service_map = {}
+
+
+def get_triggering_service(active_master):
+  """Returns a TriggeringService instance for active_master as Deferred."""
+  d = _master_triggering_service_map.get(active_master)
+  if not d:
+    d = TriggeringService.create(active_master)
+    def start(service):
+      service.start()
+      return service
+    d.addCallback(start)
+    _master_triggering_service_map[active_master] = d
+  return d
+
+
+def change_from_change_spec(self, change):
+  """Converts a change in change_spec format to buildbucket format.
+
+  For more info on change_spec format, see
+  master.chromium_step.AnnotationObserver.insertSourceStamp.
+
+  Buildbucket change format is described in README.md.
+  """
+  create_ts = None
+  if 'when_timestamp' in change:
+    # Convert from seconds to milliseconds since Unix Epoch.
+    assert isinstance(change['when_timestamp'], (int, float))
+    create_ts = change['when_timestamp'] * 1000
+
+  return {
+      'revision': change.get('revision'),
+      'author': {
+          # Assuming author is email.
+          'email': change.get('author'),
+      },
+      'create_ts': create_ts,
+      'files': [{'path': f} for f in change.get('files', [])],
+      'message': change.get('comments'),
+      'branch': change.get('branch'),
+      'url': change.get('revlink'),
+      'project': change.get('project'),
+  }
+