class Handler:
def __init__(self):
# Check is class name is properly constructed
# like SomethingHandler
if (self.__class__.__name__[-7:] != 'Handler'):
raise ValueError(
"Wrong handler class name : must be [something]Handler")
self._handler_name = (self.__class__.__name__)[0:-7].lower()
self._config = Config(self._handler_name)
logging.debug("Initializing Handler's base for %s" %
self._handler_name)
setproctitle("griotte-%s" % self._handler_name)
self._ws = WebSocket()
self._ws.add_listener("%s.command.ping" % self._handler_name,
self.ping)
logging.debug("Added ping listener for %s" % self._handler_name)
# Install signal handlers that child class can override
signal.signal(signal.SIGINT, self._signal)
signal.signal(signal.SIGTERM, self._signal)
signal.signal(signal.SIGUSR1, self._signal)
signal.signal(signal.SIGHUP, self._signal)
def _signal(self, signum, frame):
pass
def ping(self, channel, message):
self._ws.send("%s.event.pong" % self._handler_name,
{"handler": self._handler_name})
logging.debug("%s sending pong" % self._handler_name)
def send_event(self, event, data):
self._ws.send("%s.event.%s" % (self._handler_name, event), data)
def add_listener(self, command, full_path=False, callback=None):
if callback is None:
callback = getattr(self, "_wscb_%s" % command.split(".")[-1])
if full_path:
path = command
else:
path = "%s.command.%s" % (self._handler_name, command)
self._ws.add_listener(path, callback)
class Handler:
def __init__(self):
# Check is class name is properly constructed
# like SomethingHandler
if (self.__class__.__name__[-7:] != 'Handler'):
raise ValueError("Wrong handler class name : must be [something]Handler")
self._handler_name = (self.__class__.__name__)[0:-7].lower()
self._config = Config(self._handler_name)
logging.debug("Initializing Handler's base for %s" % self._handler_name)
setproctitle("griotte-%s" % self._handler_name)
self._ws = WebSocket()
self._ws.add_listener("%s.command.ping" % self._handler_name, self.ping)
logging.debug("Added ping listener for %s" % self._handler_name)
# Install signal handlers that child class can override
signal.signal(signal.SIGINT, self._signal)
signal.signal(signal.SIGTERM, self._signal)
signal.signal(signal.SIGUSR1, self._signal)
signal.signal(signal.SIGHUP, self._signal)
def _signal(self, signum, frame):
pass
def ping(self, channel, message):
self._ws.send("%s.event.pong" % self._handler_name, { "handler": self._handler_name })
logging.debug("%s sending pong" % self._handler_name)
def send_event(self, event, data):
self._ws.send("%s.event.%s" % (self._handler_name, event), data)
def add_listener(self, command, full_path=False, callback=None):
if callback is None:
callback = getattr(self, "_wscb_%s" % command.split(".")[-1])
if full_path:
path = command
else:
path = "%s.command.%s" % (self._handler_name, command)
self._ws.add_listener(path, callback)
class __Expecter:
""" Utility class that sends and receives data over websocket for server-side blocks
"""
def __init__(self, uri=None):
self._ws = WebSocket(uri=uri)
self._ws.start(watchdog_interval=2)
self._subscriptions = {}
def send_expect(self, channel_out, channel_in, data='{}', flush=False):
""" Sends a message over websocket and waits for a reply
A combination of :py:func:`send` and :py:func:`expect`
:param channel_out: The channel to write to
:type channel: str
:param channel_in: The channel to listen to
:type channel: str
:param data: The data to send
:type data: str -- json encoded
:param flush: Whether the incoming queue must be flushed before handling message (set to True to prevent receiving past messages )
:type flush: bool
"""
self._subscribe(channel_in)
if flush:
self._flush_queue(channel_in)
self._ws.send(channel_out, data)
return self._subscriptions[channel_in].get()
def send(self, channel, data='{}'):
""" Sends a message over websocket
Utility function that wraps websocket message sending and takes care of
opening a websocket if needed
:param channel: The channel to write to
:type channel: str.
:param data: The data to send
:type data: str -- json encoded
:param flush: Whether the incoming queue must be flushed before handling message (set to True to prevent receiving past messages )
:type flush: bool
"""
logging.debug("sending message on %s" % channel)
self._ws.send(channel, data)
def expect(self, channel, flush=False):
""" Expects a message on a channel
Blocks until the message arrives and returns the 'data' part of the message
:param channel: Channel to listen to
:type channel: str
:param flush: Whether the incoming queue must be flushed before handling message (set to True to prevent receiving past messages )
:type flush: bool
:rtype: dict -- the message we got on the wire
"""
self._subscribe(channel)
if flush:
self._flush_queue(channel)
data = self._subscriptions[channel].get()
logging.debug("got message on %s" % channel)
#self._unsubscribe(channel)
return data
def quit(self):
self._unsubscribe_all()
self._ws.stop()
def on_message(self, channel, data):
try:
self._subscriptions[channel].put(data)
except KeyError:
# Clients can watch wildcard channels
for watched_channel in self._subscriptions:
if fnmatch.fnmatch(channel, watched_channel):
# We had a match for watched_channel key
# We have to iterate over client list for this channel
self._subscriptions[watched_channel].put(data)
return
logging.error(
"Received a message for a channel we didn't subscribe to (%s)"
% channel)
def _flush_queue(self, channel):
logging.debug("Flushing queue for channel %s" % channel)
try:
while not self._subscriptions[channel].empty():
self._subscriptions[channel].get()
logging.debug("flushed one message")
except Empty:
return
def _subscribe(self, channel):
if channel in self._subscriptions:
return False
self._subscriptions[channel] = Queue()
logging.debug("subscribing to channel %s" % channel)
self._ws.add_listener(channel, self.on_message)
return True
def _unsubscribe(self, channel):
if channel not in self._subscriptions:
return
logging.debug("unsubscribing from channel %s" % channel)
self._ws.remove_listener(channel)
logging.debug("removing channel %s" % channel)
self._subscriptions.pop(channel)
def _unsubscribe_all(self):
for channel in self._subscriptions.copy().keys():
self._unsubscribe(channel)
class __Expecter:
""" Utility class that sends and receives data over websocket for server-side blocks
"""
def __init__(self, uri=None):
self._ws = WebSocket(uri=uri)
self._ws.start(watchdog_interval=2)
self._subscriptions = {}
def send_expect(self, channel_out, channel_in, data='{}', flush=False):
""" Sends a message over websocket and waits for a reply
A combination of :py:func:`send` and :py:func:`expect`
:param channel_out: The channel to write to
:type channel: str
:param channel_in: The channel to listen to
:type channel: str
:param data: The data to send
:type data: str -- json encoded
:param flush: Whether the incoming queue must be flushed before handling message (set to True to prevent receiving past messages )
:type flush: bool
"""
self._subscribe(channel_in)
if flush:
self._flush_queue(channel_in)
self._ws.send(channel_out, data)
return self._subscriptions[channel_in].get()
def send(self, channel, data = '{}'):
""" Sends a message over websocket
Utility function that wraps websocket message sending and takes care of
opening a websocket if needed
:param channel: The channel to write to
:type channel: str.
:param data: The data to send
:type data: str -- json encoded
:param flush: Whether the incoming queue must be flushed before handling message (set to True to prevent receiving past messages )
:type flush: bool
"""
logging.debug("sending message on %s" % channel)
self._ws.send(channel, data)
def expect(self, channel, flush=False):
""" Expects a message on a channel
Blocks until the message arrives and returns the 'data' part of the message
:param channel: Channel to listen to
:type channel: str
:param flush: Whether the incoming queue must be flushed before handling message (set to True to prevent receiving past messages )
:type flush: bool
:rtype: dict -- the message we got on the wire
"""
self._subscribe(channel)
if flush:
self._flush_queue(channel)
data = self._subscriptions[channel].get()
logging.debug("got message on %s" % channel)
#self._unsubscribe(channel)
return data
def quit(self):
self._unsubscribe_all()
self._ws.stop()
def on_message(self, channel, data):
try:
self._subscriptions[channel].put(data)
except KeyError:
# Clients can watch wildcard channels
for watched_channel in self._subscriptions:
if fnmatch.fnmatch(channel, watched_channel):
# We had a match for watched_channel key
# We have to iterate over client list for this channel
self._subscriptions[watched_channel].put(data)
return
logging.error("Received a message for a channel we didn't subscribe to (%s)" % channel)
def _flush_queue(self, channel):
logging.debug("Flushing queue for channel %s" % channel)
try:
while not self._subscriptions[channel].empty():
self._subscriptions[channel].get()
logging.debug("flushed one message")
except Empty:
return
def _subscribe(self, channel):
if channel in self._subscriptions:
return False
self._subscriptions[channel] = Queue()
logging.debug("subscribing to channel %s" % channel)
self._ws.add_listener(channel, self.on_message)
return True
def _unsubscribe(self, channel):
if channel not in self._subscriptions:
return
logging.debug("unsubscribing from channel %s" % channel)
self._ws.remove_listener(channel)
logging.debug("removing channel %s" % channel)
self._subscriptions.pop(channel)
def _unsubscribe_all(self):
for channel in self._subscriptions.copy().keys():
self._unsubscribe(channel)