class EventClient(WebSocketClient):
def __init__(self, url, filters, on_event):
- ssl_options = None
- if re.match(r'(?i)^(true|1|yes)$',
- config.get('ARVADOS_API_HOST_INSECURE', 'no')):
- ssl_options={'cert_reqs': ssl.CERT_NONE}
+ # Prefer system's CA certificates (if available)
+ ssl_options = {}
+ certs_path = '/etc/ssl/certs/ca-certificates.crt'
+ if os.path.exists(certs_path):
+ ssl_options['ca_certs'] = certs_path
+ if config.flag_is_true('ARVADOS_API_HOST_INSECURE'):
+ ssl_options['cert_reqs'] = ssl.CERT_NONE
else:
- ssl_options={'cert_reqs': ssl.CERT_REQUIRED}
+ ssl_options['cert_reqs'] = ssl.CERT_REQUIRED
+
+ # Warning: If the host part of url resolves to both IPv6 and
+ # IPv4 addresses (common with "localhost"), only one of them
+ # will be attempted -- and it might not be the right one. See
+ # ws4py's WebSocketBaseClient.__init__.
super(EventClient, self).__init__(url, ssl_options=ssl_options)
self.filters = filters
self.on_event = on_event
self.stop.wait(self.poll_time)
def run_forever(self):
- self.stop.wait()
+ # Have to poll here, otherwise KeyboardInterrupt will never get processed.
+ while not self.stop.is_set():
+ self.stop.wait(1)
def close(self):
self.stop.set()
def subscribe(api, filters, on_event, poll_fallback=15):
'''
- api: Must be a newly created from arvados.api(cache=False), not shared with the caller, as it may be used by a background thread.
+ api: a client object retrieved from arvados.api(). The caller should not use this client object for anything else after calling subscribe().
filters: Initial subscription filters.
- on_event: The callback when a message is received
+ on_event: The callback when a message is received.
poll_fallback: If websockets are not available, fall back to polling every N seconds. If poll_fallback=False, this will return None if websockets are not available.
'''
ws = None