Abort master management if the current hostname doesn't match the master's.

infra/tools/master_manager/__main__.py

 #!/usr/bin/python
 # Copyright 2015 Google Inc. All Rights Reserved.
 # pylint: disable=F0401
 
 """Start, restart and shut down masters as needed."""
 
 import argparse
 import logging
 import os
+import socket
 import subprocess
 import sys
 
 from functools import partial
 
 from infra.libs import logs
 from infra.libs.buildbot import master
 from infra.libs.service_utils import daemon
 from infra.libs.service_utils import outer_loop
 from infra.services.master_lifecycle import buildbot_state
@@ skipping 11 matching lines @@
   parser.add_argument('transition_time_utc', nargs='?', type=float,
       help='seconds since the UTC epoch to trigger the state')
   parser.add_argument('--list-all-states', action='store_true',
       help='list all states with their actions and exit')
   parser.add_argument('--enable-gclient-sync', action='store_true',
       help='perform a gclient sync before every master start')
   parser.add_argument('--emergency-file',
       default='.stop_master_lifecycle',
       help='filename of the emergency stop file. if this file is found in the '
            'master directory, exit immediately')
+  parser.add_argument('--hostname',
+      default=socket.getfqdn(),
+      help='override local hostname (currently %defaults)')

[agable, 2015/05/05 18:58:29]

%defaults? I think you need parens "%(default)s".

[ghost stip (do not use), 2015/05/05 23:41:34]

yes I did! thanks

   parser.add_argument('--prod', action='store_true',
       help='actually run commands instead of printing them.')
   parser.add_argument('--loop', action='store_true',
       help='repeatedly run the state machine. will not terminate unless killed')
   parser.add_argument('--loop-sleep-secs', type=int, default=5,
       help='how many seconds to wait between loop runs. default %(default)s')
   parser.add_argument('--connection-timeout', type=int, default=30,
       help='how many seconds to wait for a master http request before timing '
            'out.')
   outer_loop.add_argparse_options(parser)
   logs.add_argparse_options(parser)
 
   args = parser.parse_args()
   logs.process_argparse_options(args)
 
   if not args.list_all_states:
     if not args.directory:
       parser.error('A master directory must be specified.')
     if not args.transition_time_utc:
       parser.error('A transition time must be specified.')
     if not args.desired_state:
       parser.error('A desired state must be specified.')
   return args
 
 
+def master_hostname_is_valid(local_hostname, abs_master_directory, logger):
+  master_hostname = master.get_mastermap_data(
+      abs_master_directory)['fullhost']
+  if master_hostname != local_hostname:
+    logger.error('%s does not match %s, aborting. use --hostname to override.',
+        local_hostname, master_hostname)
+    return False
+  return True
+
+
 def run_state_machine_pass(
     logger, matchlist, abs_master_directory, emergency_file, desired_state,
-    transition_time_utc, enable_gclient_sync, prod, connection_timeout):
+    transition_time_utc, enable_gclient_sync, prod, connection_timeout,
+    hostname):
   # pragma: no cover
   if os.path.exists(os.path.join(abs_master_directory, emergency_file)):
     logger.error('%s detected in %s, aborting!',
         emergency_file, abs_master_directory)
     return 1
 
+  if not master_hostname_is_valid(hostname, abs_master_directory, logger):
+    return 1
+
   evidence = buildbot_state.collect_evidence(
       abs_master_directory, connection_timeout=connection_timeout)
   evidence['desired_buildbot_state'] = {
       'desired_state': desired_state,
       'transition_time_utc': transition_time_utc,
   }
 
   state, action_name, action_items = matchlist.execution_list(evidence)
   execution_list = list(
       master.convert_action_items_to_cli(
@@ skipping 28 matching lines @@
 
   if args.list_all_states:
     matchlist.print_all_states()
     return 0
 
   abs_master_directory = os.path.abspath(args.directory)
 
   state_machine = partial(run_state_machine_pass, logger,
         matchlist, abs_master_directory, args.emergency_file,
         args.desired_state, args.transition_time_utc, args.enable_gclient_sync,
-        args.prod, args.connection_timeout)
+        args.prod, args.connection_timeout, args.hostname)
 
   if args.loop:
     loop_opts = outer_loop.process_argparse_options(args)
     outer_loop.loop(
         state_machine, lambda: args.loop_sleep_secs, **loop_opts)
   else:
     return state_machine()
 
   return 0
 
 
 if __name__ == '__main__':  # pragma: no cover
   sys.exit(main())