def _event_connect(self, packet, _qos, _dup, _retain):
"""This will decode a received 'connect' packet.
"""
LOG.info('ProtocolEvent "Connect Packet" received.')
# Strip variable header
packet = packet[10:]
# Extract the connect flags
f_username = packet[0] & 0x80 == 0x80
f_password = packet[0] & 0x40 == 0x40
f_willRetain = packet[0] & 0x20 == 0x20
l_willQos = packet[0] & 0x18 >> 3
f_willFlag = packet[0] & 0x04 == 0x04
f_cleanStart = packet[0] & 0x02 == 0x02
packet = packet[1:]
keepalive = EncodeDecode._decodeValue(
packet[:2]) # Extract the keepalive period
packet = packet[2:]
clientID = EncodeDecode._decodeString(
packet) # Extract the client id_event_connect
packet = packet[len(clientID) + 2:]
# Extract the will topic and message, if applicable
l_willTopic = None
l_willMessage = None
if f_willFlag:
# Extract the will topic
l_willTopic = EncodeDecode._decodeString(packet)
packet = packet[len(l_willTopic) + 2:]
# Extract the will message
# Whatever remains is the will message
# ## l_willMessage = packet
l_willMessage = EncodeDecode._decodeString(packet)
packet = packet[len(l_willMessage) + 2:]
l_username = None
if f_username: # Extract user name if one is present.
l_username = EncodeDecode._decodeString(packet)
packet = packet[len(l_username) + 2:]
l_password = None
if f_password: # Extract password if one is present.
l_password = EncodeDecode._decodeString(packet)
packet = packet[len(l_password) + 2:]
LOG.info('Mqtt Connected.')
self.connectReceived(clientID, keepalive, l_willTopic, l_willMessage,
l_willQos, f_willRetain, f_cleanStart, l_username,
l_password)
def _event_unsubscribe(self, packet, _qos, _dup, _retain):
LOG.info('Event Unsubscribe received: {} {}'.format(
len(packet), packet))
messageId = EncodeDecode._decodeValue(packet[:2])
packet = packet[2:]
# Extract the unsubscribing topics
topics = []
while len(packet):
topic = EncodeDecode._decodeString(packet)
packet = packet[len(topic) + 2:]
topics.append(topic)
LOG.info('Mqtt UnSubscribe: {}'.format(topics))
self.unsubscribeReceived(topics, messageId)
def _event_subscribe(self, packet, qos, _dup, _retain):
LOG.info('ProtocolEvent "Subscribe Packet" received: {} {}'.format(
len(packet), packet))
messageId = EncodeDecode._decodeValue(packet[:2])
packet = packet[2:]
topics = []
while len(packet):
topic = EncodeDecode._decodeString(packet)
packet = packet[len(topic) + 2:]
qos = packet[0]
packet = packet[1:]
# Add them to the list of (topic, qos)s
topics.append((topic, qos))
LOG.info('Mqtt Subscribe: {}'.format(topics))
self.subscribeReceived(topics, messageId)
def _event_publish(self, packet, qos, dup, retain):
""" Receive a "Published" message
Here we get a published message from the broker.
Extract the parts of the packet.
@param packet: is a bytearray containing the variable header and payload combined.
"""
# Extract the topic portion of the packet.
l_topic = EncodeDecode._decodeString(packet)
packet = packet[len(l_topic) + 2:]
# Extract the message ID if appropriate
messageId = None
if qos > 0:
messageId = EncodeDecode._decodeValue(packet[:2])
packet = packet[2:]
LOG.debug('Publish MsgID:{}'.format(messageId))
# Extract whatever remains as the message
l_json = EncodeDecode._get_string(packet)
# l_json = packet.decode('utf-8')
l_message = json_tools.decode_json_unicode(l_json)
# l_topic is a string
# l_message is a string
self.publishReceived(l_topic, l_message, qos, dup, retain, messageId)