_logger = logging.getLogger('arvados.events')
+
class EventClient(WebSocketClient):
def __init__(self, url, filters, on_event, last_log_id):
ssl_options = {'ca_certs': arvados.util.ca_certs_path()}
self.filters = filters
self.on_event = on_event
self.last_log_id = last_log_id
+ self._closing_lock = threading.RLock()
+ self._closing = False
+ self._closed = threading.Event()
def opened(self):
self.subscribe(self.filters, self.last_log_id)
- def received_message(self, m):
- self.on_event(json.loads(str(m)))
+ def closed(self, code, reason=None):
+ self._closed.set()
- def close_connection(self):
- try:
- self.sock.shutdown(socket.SHUT_RDWR)
- self.sock.close()
- except:
- pass
+ def received_message(self, m):
+ with self._closing_lock:
+ if not self._closing:
+ self.on_event(json.loads(str(m)))
+
+ def close(self, code=1000, reason='', timeout=0):
+ """Close event client and optionally wait for it to finish.
+
+ :timeout: is the number of seconds to wait for ws4py to
+ indicate that the connection has closed.
+ """
+ super(EventClient, self).close(code, reason)
+ with self._closing_lock:
+ # make sure we don't process any more messages.
+ self._closing = True
+ # wait for ws4py to tell us the connection is closed.
+ self._closed.wait(timeout=timeout)
def subscribe(self, filters, last_log_id=None):
m = {"method": "subscribe", "filters": filters}
def unsubscribe(self, filters):
self.send(json.dumps({"method": "unsubscribe", "filters": filters}))
+
class PollClient(threading.Thread):
def __init__(self, api, filters, on_event, poll_time, last_log_id):
super(PollClient, self).__init__()
self.on_event = on_event
self.poll_time = poll_time
self.daemon = True
- self.stop = threading.Event()
self.last_log_id = last_log_id
+ self._closing = threading.Event()
+ self._closing_lock = threading.RLock()
def run(self):
self.id = 0
self.on_event({'status': 200})
- while not self.stop.isSet():
+ while not self._closing.is_set():
max_id = self.id
+ moreitems = False
for f in self.filters:
- items = self.api.logs().list(order="id asc", filters=f+[["id", ">", str(self.id)]]).execute()['items']
- for i in items:
+ items = self.api.logs().list(order="id asc", filters=f+[["id", ">", str(self.id)]]).execute()
+ for i in items["items"]:
if i['id'] > max_id:
max_id = i['id']
- self.on_event(i)
+ with self._closing_lock:
+ if self._closing.is_set():
+ return
+ self.on_event(i)
+ if items["items_available"] > len(items["items"]):
+ moreitems = True
self.id = max_id
- self.stop.wait(self.poll_time)
+ if not moreitems:
+ self._closing.wait(self.poll_time)
def run_forever(self):
# Have to poll here, otherwise KeyboardInterrupt will never get processed.
- while not self.stop.is_set():
- self.stop.wait(1)
+ while not self._closing.is_set():
+ self._closing.wait(1)
- def close(self):
- self.stop.set()
+ def close(self, code=None, reason=None, timeout=0):
+ """Close poll client and optionally wait for it to finish.
+
+ If an :on_event: handler is running in a different thread,
+ first wait (indefinitely) for it to return.
+
+ After closing, wait up to :timeout: seconds for the thread to
+ finish the poll request in progress (if any).
+
+ :code: and :reason: are ignored. They are present for
+ interface compatibility with EventClient.
+ """
+
+ with self._closing_lock:
+ self._closing.set()
try:
- self.join()
+ self.join(timeout=timeout)
except RuntimeError:
# "join() raises a RuntimeError if an attempt is made to join the
# current thread as that would cause a deadlock. It is also an
if not endpoint:
raise errors.FeatureNotEnabledError(
"Server does not advertise a websocket endpoint")
- uri_with_token = "{}?api_token={}".format(endpoint, api.api_token)
- client = EventClient(uri_with_token, filters, on_event, last_log_id)
- ok = False
try:
- client.connect()
- ok = True
- return client
- finally:
- if not ok:
- client.close_connection()
+ uri_with_token = "{}?api_token={}".format(endpoint, api.api_token)
+ client = EventClient(uri_with_token, filters, on_event, last_log_id)
+ ok = False
+ try:
+ client.connect()
+ ok = True
+ return client
+ finally:
+ if not ok:
+ client.close_connection()
+ except:
+ _logger.warn("Failed to connect to websockets on %s" % endpoint)
+ raise
+
def subscribe(api, filters, on_event, poll_fallback=15, last_log_id=None):
"""