scheduler/status_server.py

   1 import os, BaseHTTPServer, cgi, threading, urllib, fcntl, logging
   2 import common
   3 from autotest_lib.scheduler import drone_manager, scheduler_config
   4
   5 _PORT = 13467
   6
   7 _HEADER = """
   8 <html>
   9 <head><title>Scheduler status</title></head>
  10 <body>
  11 Actions:<br>
  12 <a href="?reparse_config=1">Reparse global config values</a><br>
  13 <a href="?restart_scheduler=1">Restart the scheduler</a><br>
  14 <br>
  15 """
  16
  17 _FOOTER = """
  18 </body>
  19 </html>
  20 """
  21
  22 class StatusServerRequestHandler(BaseHTTPServer.BaseHTTPRequestHandler):
  23     def _send_headers(self):
  24         self.send_response(200, 'OK')
  25         self.send_header('Content-Type', 'text/html')
  26         self.end_headers()
  27
  28
  29     def _parse_arguments(self):
  30         path_parts = self.path.split('?', 1)
  31         if len(path_parts) == 1:
  32             return {}
  33
  34         encoded_args = path_parts[1]
  35         return cgi.parse_qs(encoded_args)
  36
  37
  38     def _write_line(self, line=''):
  39         self.wfile.write(line + '<br>\n')
  40
  41
  42     def _write_field(self, field, value):
  43         self._write_line('%s=%s' % (field, value))
  44
  45
  46     def _write_all_fields(self):
  47         self._write_line('Config values:')
  48         for field in scheduler_config.SchedulerConfig.FIELDS:
  49             self._write_field(field, getattr(scheduler_config.config, field))
  50         self._write_line()
  51
  52
  53     def _write_drone(self, drone):
  54         if drone.allowed_users:
  55             allowed_users = ', '.join(drone.allowed_users)
  56         else:
  57             allowed_users = 'all'
  58         line = ('%s: %s/%s processes, users: %s'
  59                 % (drone.hostname, drone.active_processes, drone.max_processes,
  60                    allowed_users))
  61         if not drone.enabled:
  62             line += ' (disabled)'
  63         self._write_line(line)
  64
  65
  66     def _write_drone_list(self):
  67         self._write_line('Drones:')
  68         for drone in self.server._drone_manager.get_drones():
  69             self._write_drone(drone)
  70         self._write_line()
  71
  72
  73     def _execute_actions(self, arguments):
  74         if 'reparse_config' in arguments:
  75             scheduler_config.config.read_config()
  76             self.server._drone_manager.refresh_drone_configs()
  77             self._write_line('Reparsed config!')
  78         elif 'restart_scheduler' in arguments:
  79             self.server._shutdown_scheduler = True
  80             self._write_line('Posted the shutdown request')
  81         self._write_line()
  82
  83
  84     def do_GET(self):
  85         self._send_headers()
  86         self.wfile.write(_HEADER)
  87
  88         arguments = self._parse_arguments()
  89         self._execute_actions(arguments)
  90         self._write_all_fields()
  91         self._write_drone_list()
  92
  93         self.wfile.write(_FOOTER)
  94
  95
  96 class StatusServer(BaseHTTPServer.HTTPServer):
  97     def __init__(self):
  98         address = ('', _PORT)
  99         # HTTPServer is an old-style class :(
 100         BaseHTTPServer.HTTPServer.__init__(self, address,
 101                                            StatusServerRequestHandler)
 102         self._shutting_down = False
 103         self._drone_manager = drone_manager.instance()
 104         self._shutdown_scheduler = False
 105
 106         # ensure the listening socket is not inherited by child processes
 107         old_flags = fcntl.fcntl(self.fileno(), fcntl.F_GETFD)
 108         fcntl.fcntl(self.fileno(), fcntl.F_SETFD, old_flags | fcntl.FD_CLOEXEC)
 109
 110
 111     def shutdown(self):
 112         if self._shutting_down:
 113             return
 114         logging.info('Shutting down server...')
 115         self._shutting_down = True
 116         # make one last request to awaken the server thread and make it exit
 117         urllib.urlopen('http://localhost:%s' % _PORT)
 118
 119
 120     def _serve_until_shutdown(self):
 121         logging.info('Status server running on %s', self.server_address)
 122         while not self._shutting_down:
 123             self.handle_request()
 124
 125
 126     def start(self):
 127         self._thread = threading.Thread(target=self._serve_until_shutdown,
 128                                         name='status_server')
 129         self._thread.start()