services/nodemanager/arvnodeman/status.py

   1 # Copyright (C) The Arvados Authors. All rights reserved.
   2 #
   3 # SPDX-License-Identifier: AGPL-3.0
   4
   5 from __future__ import absolute_import, print_function
   6 from future import standard_library
   7
   8 import http.server
   9 import json
  10 import logging
  11 import socketserver
  12 import threading
  13
  14 _logger = logging.getLogger('status.Handler')
  15
  16
  17 class Server(socketserver.ThreadingMixIn, http.server.HTTPServer, object):
  18     def __init__(self, config):
  19         port = config.getint('Manage', 'port')
  20         self.enabled = port >= 0
  21         if not self.enabled:
  22             _logger.warning("Management server disabled. "+
  23                             "Use [Manage] config section to enable.")
  24             return
  25         self._config = config
  26         self._tracker = tracker
  27         super(Server, self).__init__(
  28             (config.get('Manage', 'address'), port), Handler)
  29         self._thread = threading.Thread(target=self.serve_forever)
  30         self._thread.daemon = True
  31
  32     def start(self):
  33         if self.enabled:
  34             self._thread.start()
  35
  36
  37 class Handler(http.server.BaseHTTPRequestHandler, object):
  38     def do_GET(self):
  39         if self.path == '/status.json':
  40             self.send_response(200)
  41             self.send_header('Content-type', 'application/json')
  42             self.end_headers()
  43             self.wfile.write(tracker.get_json())
  44         else:
  45             self.send_response(404)
  46
  47     def log_message(self, fmt, *args, **kwargs):
  48         _logger.info(fmt, *args, **kwargs)
  49
  50
  51 class Tracker(object):
  52     def __init__(self):
  53         self._mtx = threading.Lock()
  54         self._latest = {}
  55
  56     def get_json(self):
  57         with self._mtx:
  58             return json.dumps(self._latest)
  59
  60     def keys(self):
  61         with self._mtx:
  62             return self._latest.keys()
  63
  64     def update(self, updates):
  65         with self._mtx:
  66             self._latest.update(updates)
  67
  68
  69 tracker = Tracker()