sdk/python/arvados/events.py

   1 from ws4py.client.threadedclient import WebSocketClient
   2 import thread
   3 import json
   4 import os
   5 import time
   6 import ssl
   7 import re
   8 import config
   9 import logging
  10
  11 _logger = logging.getLogger('arvados.events')
  12
  13 class EventClient(WebSocketClient):
  14     def __init__(self, url, filters, on_event):
  15         ssl_options = None
  16         if re.match(r'(?i)^(true|1|yes)$',
  17                     config.get('ARVADOS_API_HOST_INSECURE', 'no')):
  18             ssl_options={'cert_reqs': ssl.CERT_NONE}
  19         else:
  20             ssl_options={'cert_reqs': ssl.CERT_REQUIRED}
  21
  22         super(EventClient, self).__init__(url, ssl_options)
  23         self.filters = filters
  24         self.on_event = on_event
  25
  26     def opened(self):
  27         self.send(json.dumps({"method": "subscribe", "filters": self.filters}))
  28
  29     def received_message(self, m):
  30         self.on_event(json.loads(str(m)))
  31
  32     def close_connection(self):
  33         try:
  34             self.sock.shutdown(socket.SHUT_RDWR)
  35             self.sock.close()
  36         except:
  37             pass
  38
  39 def subscribe(api, filters, on_event):
  40     ws = None
  41     try:
  42         url = "{}?api_token={}".format(api._rootDesc['websocketUrl'], config.get('ARVADOS_API_TOKEN'))
  43         ws = EventClient(url, filters, on_event)
  44         ws.connect()
  45         return ws
  46     except Exception:
  47         _logger.exception('')
  48         if (ws):
  49           ws.close_connection()
  50         raise