Add master_manager_launch script which launches master_manager scripts for each master on a host.

infra/libs/buildbot/master.py

 # 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.
 
 """Get information about a buildbot master and manipulate it."""
 
 
 import errno
 import os
 import json
@@ skipping 75 matching lines @@
   """
   last_boot = get_last_boot(directory)
   last_no_new_builds = _get_last_action(directory, 'make no-new-builds')
   if not last_no_new_builds:
     return None
   if last_boot > last_no_new_builds:
     return None
   return last_no_new_builds
 
 
-def get_mastermap_data(directory):
-  """Get mastermap JSON from a master directory."""
+def _call_mastermap(build_dir):
+  """Given a build/ directory, obtain the full mastermap.json.
 
-  build_dir = os.path.join(directory, os.pardir, os.pardir, os.pardir, 'build')
+  This checks if build_internal/ is checked out next to build/ and uses
+  mastermap_internal.py if present.
+  """
   runit = os.path.join(build_dir, 'scripts', 'tools', 'runit.py')
-  build_internal_dir = os.path.join(build_dir, os.pardir, 'build_internal')
+  build_internal_dir = os.path.join(
+      os.path.dirname(build_dir), 'build_internal')
 
   script_path = os.path.join(build_dir, 'scripts', 'tools', 'mastermap.py')
   if os.path.exists(build_internal_dir):
     script_path = os.path.join(
          build_internal_dir, 'scripts', 'tools', 'mastermap_internal.py')
 
-  script_data = json.loads(subprocess.check_output(
+  return json.loads(subprocess.check_output(
     [runit, script_path, '-f', 'json']))
 
+
+def get_mastermap_for_host(build_dir, hostname):
+  """Get mastermap JSON for all masters on a specific host."""
+  script_data = _call_mastermap(build_dir)
+  return [x for x in script_data if x.get('fullhost') == hostname]
+
+
+def get_mastermap_data(directory):
+  """Get mastermap JSON for a specific master."""
+
+  build_dir = os.path.join(
+      os.path.dirname(os.path.dirname(os.path.dirname(directory))), 'build')
+  script_data = _call_mastermap(build_dir)
+
   short_dirname = os.path.basename(directory)
   matches = [x for x in script_data if x.get('dirname') == short_dirname]
   assert len(matches) < 2, (
       'Multiple masters were found with the same master directory.')
   if matches:
     return matches[0]
   return None
 
 
 def _get_master_web_port(directory):
@@ skipping 66 matching lines @@
     elif action_item == MakeStop:
       yield cmd_dict(['make', 'stop'], 'make')
     elif action_item == MakeWait:
       yield cmd_dict(['make', 'wait'], 'make')
     elif action_item == MakeStart:
       yield cmd_dict(['make', 'start'], 'make')
     elif action_item == MakeNoNewBuilds:
       yield cmd_dict(['make', 'no-new-builds'], 'make')
     else:
       raise ValueError('Invalid action item %s' % action_item)