def __init__(self, message_from_broker, loops = []):
"""
constructor for RPiIottlyAgent
message_from_broker: callback to which notify to client the incoming messages from broker
loops: list of functions which will be run in one thread each inside and infinite loop
to provide threading support to the user code
"""
super(RPiIottlyAgent, self).__init__()
self.broker_process = None
self.message_from_broker = message_from_broker
self.loops = loops
self.flashmanager = FlashManager(self.send_msg, self.close)
self.child_conn, self.parent_conn = multiprocessing.Pipe()
self.msg_queue = multiprocessing.Queue()
signal.signal(signal.SIGTERM, self.sig_handler)
signal.signal(signal.SIGINT, self.sig_handler)
signal.signal(signal.SIGSEGV, self.sig_handler)
class RPiIottlyAgent(object):
"""
Raspberry Pi IOTTLY Angent base class
Method:
__init__
start
send_msg
close
"""
def __init__(self, message_from_broker, loops = []):
"""
constructor for RPiIottlyAgent
message_from_broker: callback to which notify to client the incoming messages from broker
loops: list of functions which will be run in one thread each inside and infinite loop
to provide threading support to the user code
"""
super(RPiIottlyAgent, self).__init__()
self.broker_process = None
self.message_from_broker = message_from_broker
self.loops = loops
self.flashmanager = FlashManager(self.send_msg, self.close)
self.child_conn, self.parent_conn = multiprocessing.Pipe()
self.msg_queue = multiprocessing.Queue()
signal.signal(signal.SIGTERM, self.sig_handler)
signal.signal(signal.SIGINT, self.sig_handler)
signal.signal(signal.SIGSEGV, self.sig_handler)
def sig_handler(self, _signo, _stack_frame):
if _signo in [signal.SIGTERM, signal.SIGINT]:
if multiprocessing.current_process().name == 'MainProcess':
logging.info("closing")
self.close()
def handle_message(self, msg):
logging.info(msg)
msg_string = msg["msg"]
if msg_string.startswith('/json'):
# decode json message
json_content = {}
try:
json_content = json.loads(msg_string[6:])
except ValueError:
logging.error("JSON parsing has failed for "+msg_string[6:])
if json_content.get("fw"):
self.flashmanager.handle_message(json_content)
elif self.message_from_broker:
self.message_from_broker(json_content)
else:
logging.info("bad message: %s" % msg)
def connectionstatuschanged(self, status, prestartmessages):
if status == rxb.CONNECTED:
#start loops thread
for l in self.loops:
lw = loop_worker.LoopWorker(loop_func=l, send_msg=self.send_msg)
lw.start()
return True
elif status == rxb.NOROUTETOHOST:
time.sleep(30)
self.start()
return False
elif status == rxb.PARAMERROR:
logging.info('Ask for params to {}'.format(settings.IOTTLY_REGISTRATION_SERVICE))
try:
mac = network.getHwAddr('eth0')
logging.info('device mac: {}'.format(mac))
if settings.IOTTLY_REGISTRATION_PROTOCOL == 'http':
connection = http.client.HTTPConnection(settings.IOTTLY_REGISTRATION_HOST)
else:
logging.info('HTTPS connection')
#python 3.4.3 changed default for unverified
try:
context = ssl._create_unverified_context()
except:
context = None
connection = http.client.HTTPSConnection(host=settings.IOTTLY_REGISTRATION_HOST, context=context)
reg_url = '{}/{}'.format(settings.IOTTLY_REGISTRATION_SERVICE, mac)
logging.info(reg_url)
connection.request('GET', reg_url)
response = json.loads(connection.getresponse().read().decode())
if 'error' in response.keys():
raise Exception(response['error'])
settings.update(response)
self.start(prestartmessages)
except Exception as e:
logging.info(e)
logging.info('Error retrieving params from IOTTLY')
return False
def start(self, prestartmessages):
"""
starts the AGENT
behaviour:
the support threads for functions in loops list are started first in non-blocking mode
xmpp communication is then started in blocking mode
"""
#create uploadfirmware dir:
if not os.path.exists(settings.IOTTLY_USERPACKAGE_UPLOAD_DIR):
os.makedirs(settings.IOTTLY_USERPACKAGE_UPLOAD_DIR)
try:
logging.info('msg_queue: {}'.format(self.msg_queue.qsize()))
self.broker_process = rxb.init(
(settings.IOTTLY_XMPP_SERVER_HOST, settings.IOTTLY_XMPP_SERVER_PORT),
settings.IOTTLY_XMPP_DEVICE_USER + '/IB',
settings.IOTTLY_XMPP_DEVICE_PASSWORD,
self.handle_message,
self.msg_queue, self.child_conn)
except:
self.child_conn.send(rxb.PARAMERROR)
# start can call itself resulting in multiple execution waiting for recv() == "close"
# filter only the execution which produced the "CONNECTED" state
if self.connectionstatuschanged(self.parent_conn.recv(), prestartmessages):
if prestartmessages:
for msg in prestartmessages:
self.send_msg(msg)
if multiprocessing.current_process().name == 'MainProcess':
# this is the blocking action on which the main process waits forever
if self.parent_conn.recv() == "close":
self._close()
def send_msg(self, msg):
"""
sends messages to the IOTTLY broker
it is to be used by client code to send messages
"""
self.msg_queue.put(dict(to=settings.IOTTLY_XMPP_SERVER_USER,msg='/json ' + json.dumps(msg)))
def close(self):
# close kills all the child processes
# after having killed them it joins on each to wait for the child to really exit
# in a multiprocess app child processes can't join other child process
# only the parent process can join on its children
# BUT if the close command is incoming from a broker message (a command from iottly)
# then the execution process for the close is the msg_process which is itself a child
# and hence not able to join on each of the other children
# SO: the close command is enqueued to the parent process so that it can join
# the children
self.child_conn.send("close")
def _close(self):
"""Closes eventually running threads serving the functions in the loops list"""
#to kill children loop over native children list
#DO NOT create a custom process list
#since terminated processes don't get correctly garbage collected
for lw in multiprocessing.active_children():
if type(lw) == loop_worker.LoopWorker:
lw.kill()
logging.info("Closing Agent")
closemsg = {'process': {
'name': multiprocessing.current_process().name,
'status': 'closed'}}
self.msg_queue.put(dict(to=settings.IOTTLY_XMPP_SERVER_USER,msg='/json ' + json.dumps(closemsg)))
self.msg_queue.put(None)
if self.broker_process:
self.broker_process.join()
logging.info("Agent closed")
