homie-ota.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

__author__    = 'Jan-Piet Mens <jpmens()gmail.com> & Ben Jones'
__copyright__ = 'Copyright 2016 Jan-Piet Mens'

# wget http://bottlepy.org/bottle.py
# ... or ... pip install bottle
from bottle import auth_basic, get, route, request, run, static_file, HTTPResponse, template, abort
import paho.mqtt.client as paho   # pip install paho-mqtt
import os
import signal
import sys
import hashlib
import logging
import atexit
from persist import PersistentDict
import json
import fileinput
import time
import re
import base64

try:
    import ConfigParser as configparser
except ImportError:
    import configparser

try:
    from StringIO import StringIO
except ImportError:
    from io import StringIO

# Script name (without extension) used for config/logfile names
APPNAME = os.path.splitext(os.path.basename(__file__))[0]
INIFILE = os.getenv('INIFILE', APPNAME + '.ini')
LOGFILE = os.getenv('LOGFILE', APPNAME + '.log')

# max length that Homie will accept when publishing to $ota
OTA_HOMIE_PAYLOAD_MAX_LENGTH = 16

# Read the config file
if not os.path.exists(INIFILE):
    logging.error("Cannot open ini file %s." % (INIFILE))
    sys.exit(2)
config = configparser.RawConfigParser()
config.read(INIFILE)

# Use ConfigParser to pick out the settings
DEBUG = config.getboolean("global", "DEBUG")
try:
    DEBUG_SENSOR = config.getboolean("global", "DEBUG_SENSOR")
except:
    DEBUG_SENSOR = True
OTA_HOST = config.get("global", "OTA_HOST")
OTA_PORT = config.getint("global", "OTA_PORT")
OTA_ENDPOINT = config.get("global", "OTA_ENDPOINT")
OTA_FIRMWARE_ROOT = config.get("global", "OTA_FIRMWARE_ROOT")
OTA_BASE_URL = ""
try:
    OTA_BASE_URL = config.get("global", "OTA_BASE_URL")
except:
    pass
OTA_FIRMWARE_BASE64 = True
try:
    OTA_FIRMWARE_BASE64 = config.getboolean("global", "OTA_FIRMWARE_BASE64")
except:
    pass
try:
    HTTP_USER = config.get("global","HTTP_USER")
except:
    pass
try:
    HTTP_PASSWORD = config.get("global","HTTP_PASSWORD")
except:
    pass
MQTT_HOST = config.get("mqtt", "MQTT_HOST")
MQTT_PORT = config.getint("mqtt", "MQTT_PORT")
MQTT_USERNAME = None
MQTT_PASSWORD = None
MQTT_CAFILE = None
try:
    MQTT_USERNAME = config.get("mqtt", "MQTT_USERNAME")
except:
    pass
try:
    MQTT_PASSWORD = config.get("mqtt", "MQTT_PASSWORD")
except:
    pass
try:
    MQTT_CAFILE = config.get("mqtt", "MQTT_CAFILE")
except:
    pass
MQTT_SENSOR_PREFIX = config.get("mqtt", "MQTT_SENSOR_PREFIX")


# Initialise logging
LOGFORMAT = '%(asctime)-15s %(levelname)-5s %(message)s'

if DEBUG:
    logging.basicConfig(filename=LOGFILE,
                        level=logging.DEBUG,
                        format=LOGFORMAT)
else:
    logging.basicConfig(filename=LOGFILE,
                        level=logging.INFO,
                        format=LOGFORMAT)

logging.info("Starting " + APPNAME)
logging.info("INFO MODE")
logging.debug("DEBUG MODE")
logging.debug("INIFILE = %s" % INIFILE)

# MQTT client
mqttc = paho.Client("%s-%d" % (APPNAME, os.getpid()), clean_session=True, userdata=None, protocol=paho.MQTTv311)

# Persisted inventory store
db = PersistentDict(os.path.join(OTA_FIRMWARE_ROOT, 'inventory.json'), 'c', format='json')
sensors = PersistentDict(os.path.join(OTA_FIRMWARE_ROOT, 'sensors.json'), 'c', format='json')

def check(user, pw):
    # Check user/pw here and return True/False
    if  user == HTTP_USER and pw == HTTP_PASSWORD:
        return True
    else:
        return False

def conditional_decorator(condition, decorator):
    return decorator if condition else lambda x: x

def generate_ota_payload(firmware):
    # if no '@' then payload is just a version number
    if '@' not in firmware:
        return firmware

    fw_name, fw_version = firmware.split('@')
    hash = hashlib.sha1()
    hash.update(fw_name)

    # ensure our hash doesn't make our payload too big
    fw_hashlen = OTA_HOMIE_PAYLOAD_MAX_LENGTH - len(fw_version) - 1
    fw_hash = hash.hexdigest()[:fw_hashlen]

    # ota payload is <hash>@<version>
    return "%s@%s" % (fw_hash, fw_version)

def handleterm(signum, frame):
    logging.info("SIGTERM received")
    sys.exit(0)

def exitus():
    db.sync()
    db.close()
    sensors.sync()
    sensors.close()
    logging.info("CIAO")

def uptime(seconds=0):
    MINUTE = 60
    HOUR = MINUTE * 60
    DAY = HOUR * 24

    seconds = int(seconds)

    days    = int( seconds / DAY )
    hours   = int( ( seconds % DAY ) / HOUR )
    minutes = int( ( seconds % HOUR ) / MINUTE )
    seconds = int( seconds % MINUTE )

    string = ""
    if days > 0:
        string += str(days) + " " + (days == 1 and "day" or "days" ) + ", "

    string = string + "%d:%02d:%02d" % (hours, minutes, seconds)

    return string


@get('/blurb')
@conditional_decorator('HTTP_USER' in globals() and 'HTTP_PASSWORD' in globals(), auth_basic(check))
def blurb():
    text =  """Homie OTA server running.
    OTA endpoint is: http://{host}:{port}/{endpoint}
    Firmware root is {fwroot}\n""".format(host=OTA_HOST,
            port=OTA_PORT, endpoint=OTA_ENDPOINT, fwroot=OTA_FIRMWARE_ROOT)

    for root, dirs, files in os.walk(OTA_FIRMWARE_ROOT):
        path = root.split('/')
        text = text + "\t%s %s\n" % ((len(path) - 1) * '--', os.path.basename(root))
        for file in files:
            if file[0] == '.':
                continue
            text = text + "\t\t%s %s\n" % (len(path) * '---', file)

    return text

@get('/firmware')
@conditional_decorator('HTTP_USER' in globals() and 'HTTP_PASSWORD' in globals(), auth_basic(check))
def firmware():
    fw = scan_firmware()
    return template('templates/firmware', base_url=OTA_BASE_URL, fw=fw)

@get('/')
@conditional_decorator('HTTP_USER' in globals() and 'HTTP_PASSWORD' in globals(), auth_basic(check))
def inventory():
    fw = scan_firmware()
    return template('templates/inventory', base_url=OTA_BASE_URL, db=db, fw=fw)

@get('/<filename:re:.*\.css>')
@conditional_decorator('HTTP_USER' in globals() and 'HTTP_PASSWORD' in globals(), auth_basic(check))
def stylesheets(filename):
    return static_file(filename, root='static/css')

@get('/<filename:re:.*\.png>')
@conditional_decorator('HTTP_USER' in globals() and 'HTTP_PASSWORD' in globals(), auth_basic(check))
def png(filename):
    return static_file(filename, root='static/img')

@get('/<filename:re:.*\.js>')
@conditional_decorator('HTTP_USER' in globals() and 'HTTP_PASSWORD' in globals(), auth_basic(check))
def javascript(filename):
    return static_file(filename, root='static/js')

@get('/log')
@conditional_decorator('HTTP_USER' in globals() and 'HTTP_PASSWORD' in globals(), auth_basic(check))
def showlog():
    logdata = open(LOGFILE, "r").read()
    return template('templates/log', base_url=OTA_BASE_URL, data=logdata)

@get('/device/<device>')
@conditional_decorator('HTTP_USER' in globals() and 'HTTP_PASSWORD' in globals(), auth_basic(check))
def showdevice(device):

    data = None
    sensor = {}
    if device in db:
        data = db[device]

    if device in sensors:
        sensor = sensors[device]

    return template('templates/device', base_url=OTA_BASE_URL, device=device, data=data, sensor=sensor)

@route('/firmware/<fw_file>', method='DELETE')
@conditional_decorator('HTTP_USER' in globals() and 'HTTP_PASSWORD' in globals(), auth_basic(check))
def delete(fw_file):
    fw_path = os.path.join(OTA_FIRMWARE_ROOT, fw_file)

    if not os.path.exists(fw_path):
        resp = "Unable to delete firmware %s, does not exist" % (fw_path)
        logging.warn(resp)

        abort(404, resp)
        return resp

    filename, file_ext = os.path.splitext(fw_file)
    description_file = filename + '.txt'
    description_path = os.path.join(OTA_FIRMWARE_ROOT, description_file)

    if os.path.exists(description_path):
        os.remove(description_path)

    os.remove(fw_path)

    resp = "Deleted firmware %s" % (fw_file)
    logging.info(resp)
    return resp

@route('/upload', method='POST')
@conditional_decorator('HTTP_USER' in globals() and 'HTTP_PASSWORD' in globals(), auth_basic(check))
def upload():
    '''Accept an uploaded, compiled binary sketch and obtain the firmware's
       name and version from the magic described in
       https://github.com/jpmens/homie-ota/issues/1
       Store the binary firmware into a corresponding subdirectory in firmwares/
       '''

    upload = request.files.upload
    description = request.forms.get('description')

    if upload and upload.file:
        firmware_binary = upload.file.read()
        filename = upload.filename

        regex_name = re.compile(b"\xbf\x84\xe4\x13\x54(.+)\x93\x44\x6b\xa7\x75")
        regex_version = re.compile(b"\x6a\x3f\x3e\x0e\xe1(.+)\xb0\x30\x48\xd4\x1a")

        regex_name_result = regex_name.search(firmware_binary)
        regex_version_result = regex_version.search(firmware_binary)

        if not regex_name_result or not regex_version_result:
            resp = "No valid firmware in %s" % filename
            logging.info(resp)
            return resp

        fwname = regex_name_result.group(1)
        fwversion = regex_version_result.group(1)
        fw_file = os.path.join(OTA_FIRMWARE_ROOT, fwname + '-' + fwversion + '.bin')
        description_file = os.path.join(OTA_FIRMWARE_ROOT, fwname + '-' + fwversion + '.txt')

        try:
            f = open(fw_file, "wb")
            f.write(firmware_binary)
            f.close()
        except Exception as e:
            resp = "Cannot write %s: %s" % (fw_file, str(e))
            logging.info(resp)
            return resp

        try:
            f = open(description_file, "wb")
            f.write(description)
            f.close()
        except Exception as e:
            resp = "Cannot write description to file %s: %s" % (description_file, str(e))
            logging.info(resp)
            return resp

        resp = "Firmware from %s uploaded as %s" % (filename, fw_file)
        logging.info(resp)
        return resp

    return "File is missing"

@route('/update', method='POST')
@conditional_decorator('HTTP_USER' in globals() and 'HTTP_PASSWORD' in globals(), auth_basic(check))
def update():
    device = request.forms.get('device')
    firmware = request.forms.get('firmware')

    if device == '-':
        logging.error("OTA request is aborted due to no device chosen")
        return "OTA request aborted; no device chosen"
    if firmware == '-':
        logging.error("OTA request is aborted due to no firmware chosen")
        return "OTA request aborted; no firmware chosen"

    # we are dealing with a homie 2.0 device
    if not device in db :
        info = "Unable to find {} in device list".format(device)
        logging.error(info)
    elif 'homie' in db[device]:
        logging.debug("Homie 2.0 device")
        try:
            (fwname, fwversion) = firmware.split('@')
            logging.debug("Firmware Name: {}, Firmware Version: {}".format(fwname, fwversion))
            for fwdata in scan_firmware().values():
                if fwname == fwdata['firmware'] and fwversion == fwdata['version']:
                    fwread = open("%s/%s" % (OTA_FIRMWARE_ROOT, fwdata['filename']), "r").read()
                    if OTA_FIRMWARE_BASE64:
                        fwpublish = base64.b64encode(fwread)
                    else:
                        fwpublish = bytearray(fwread)
                    m = hashlib.md5()
                    m.update(fwread)
                    fwchecksum = m.hexdigest()
                    topic = "%s/%s/$implementation/ota/firmware/%s" % (MQTT_SENSOR_PREFIX, device, fwchecksum)
                    mqttc.publish(topic, payload=fwpublish, qos=1, retain=False)
                    logging.debug("Firware checksum: {}".format(fwchecksum))
                    info = "OTA request sent to device %s for update to %s (OTA version: 2.0)" % (device, firmware)
                    logging.info(info)
                    break
            else:
                info = "Unable to find the firmware in folder"
                logging.error(info)
        except Exception as e:
            info = str(e)
            logging.error("Generic error: {}".format(str(e)))
    else:
        logging.debug("Homie 1.5 device")
        topic = "%s/%s/$ota" % (MQTT_SENSOR_PREFIX, device)
        payload = generate_ota_payload(firmware)
        mqttc.publish(topic, payload=payload, qos=1, retain=False)
        info = "OTA request sent to device %s for update to %s (OTA version: 1.5)" % (device, firmware)
        logging.info(info)
    return info

# Handle deleting a device from the mqtt broker, and the local db.
@route('/device/<device_id>', method='DELETE')
@conditional_decorator('HTTP_USER' in globals() and 'HTTP_PASSWORD' in globals(), auth_basic(check))
def delete_device(device_id):
    topics = "%s/%s/#" % (MQTT_SENSOR_PREFIX, device_id)
    mqttc.loop_stop()
    mqttc.subscribe(topics, 0)
    mqttc.message_callback_add(topics, on_delete_message)
    mqttc.loop_start()
    logging.info("Starting delete of topics for device %s" % (device_id))

    # Give the callback time before returning
    time.sleep(2)

    mqttc.loop_stop()
    mqttc.message_callback_remove(topics)
    mqttc.unsubscribe(topics)
    mqttc.loop_start()
    info = "Deleted topics for %s" % (device_id)
    logging.info(info)
    del db[device_id]
    del sensors[device_id]

    return info

def scan_firmware():
    fw = {}
    for fw_file in os.listdir(OTA_FIRMWARE_ROOT):
        fw_path = os.path.join(OTA_FIRMWARE_ROOT, fw_file)
        if not os.path.isfile(fw_path):
            continue
        if not fw_file.endswith('.bin'):
            continue

        regex = re.compile("(.*)\-((\d+\.\d+\.\d+\.\d+)|(\d+\.\d+.\d+))\.bin")
        regex_result = regex.search(fw_file)

        if not regex_result:
            logging.debug("Could not parse firmware details from %s, skipping" % (fw_file))
            continue

        fw[fw_file] = {}
        fw[fw_file]['filename'] = fw_file
        firmware = regex_result.group(1)
        version = regex_result.group(2)
        fw[fw_file]['firmware'] = firmware
        fw[fw_file]['version'] = version

        description = ""
        try:
            description = open("%s/%s-%s.txt" % (OTA_FIRMWARE_ROOT, firmware, version), "r").read()
        except:
            pass
        fw[fw_file]['description'] = description


        stat = os.stat(fw_path)
        fw[fw_file]['size'] = stat.st_size

    #print json.dumps(fw, indent=4)
    return fw


# header X-Esp8266-Ap-Mac = 1A:FE:34:D4:06:55
# header X-Esp8266-Sketch-Size = 367776
# header X-Esp8266-Sta-Mac = 18:FE:34:D4:06:55
# header X-Esp8266-Free-Space = 679936
# header X-Esp8266-Chip-Size = 4194304
# header X-Esp8266-Mode = sketch
# header Content-Length =
# header X-Esp8266-Sdk-Version = 1.5.3(aec24ac9)
# header Host = 192.168.1.130:9080
# header Connection = close
# header User-Agent = ESP8266-http-Update
# header X-Esp8266-Version = d40655e0=button-homie@1.0.0->a75ebc7c7f@1.0.1
# header Content-Type = text/plain

@get(OTA_ENDPOINT)
def ota():

    headers = request.headers
    for k in headers:
        logging.debug("header " + k + ' = ' + headers[k])

    try:
        if '->' in headers.get('X-Esp8266-Version', None):
            # X-Esp8266-Version = d40655e0=button-homie@1.0.0->a75ebc7c7f@1.0.1
            device, f = headers.get('X-Esp8266-Version', None).split('=')
            firmware_name, have_version, want_version = f.split('@')
        else:
            # X-Esp8266-Version = cf3a07e0=h-sensor=1.0.1=1.0.2
            device, firmware_name, have_version, want_version = headers.get('X-Esp8266-Version', None).split('=')
    except:
        raise
        logging.warn("Can't find X-Esp8266-Version in headers; returning 403")
        return HTTPResponse(status=403, body="Not permitted")

    # Record additional detains in DB
    if device not in db:
        db[device] = {}
    db[device]['mac']           = headers.get('X-Esp8266-Ap-Mac', None)
    db[device]['free_space']    = headers.get('X-Esp8266-Free-Space', None)
    db[device]['chip_size']     = headers.get('X-Esp8266-Chip-Size', None)
    db[device]['sketch_size']   = headers.get('X-Esp8266-Sketch-Size', None)

    logging.info("Homie firmware=%s, have=%s, want=%s on device=%s" % (firmware_name, have_version, want_version, device))

    # if the want_version contains the special '@' separator then
    # this is a request from ourselves with both fw_name and
    # fw_version included - allowing for fw changes
    fw_file = None
    if '@' in want_version:
        fw = scan_firmware()
        for fw_key in fw:
            firmware = "%s@%s" % (fw[fw_key]['firmware'], fw[fw_key]['version'])
            if generate_ota_payload(firmware) == want_version:
                fw_file = fw[fw_key]['filename']
                break
    else:
        fw_name = firmware_name
        fw_version = want_version
        fw_file = "%s-%s.bin" % (fw_name, fw_version)

    if fw_file is None:
        logging.warn("Firmware not found, %s does not match any firmware in our list; returning 304" % (want_version))
        return HTTPResponse(status=304, body="OTA aborted, firmware not found")

    fw_path = os.path.join(OTA_FIRMWARE_ROOT, fw_file)
    if not os.path.exists(fw_path):
        logging.warn("%s not found; returning 304" % (fw_path))
        return HTTPResponse(status=304, body="OTA aborted, firmware not found")

    # check free space vs .bin file on disk and refuse
    stat = os.stat(fw_path)
    fw_size = stat.st_size
    try:
        free_space = headers.get('X-Esp8266-Free-Space', None)
        if free_space and free_space < fw_size:
            logging.warn("Firmware too big, %d free on device but binary is %d; returning 304" % (free_space, fw_size))
            return HTTPResponse(status=304, body="OTA aborted, not enough free space on device")
    except:
        logging.warn("Can't find X-Esp8266-Free-Space in headers; skipping size checks")

    logging.info("Returning OTA firmware %s" % (fw_path))
    return static_file(fw_file, root=OTA_FIRMWARE_ROOT)


def on_connect(mosq, userdata, flags, rc):
    mqttc.subscribe("%s/+/+" % (MQTT_SENSOR_PREFIX), 0)
    mqttc.subscribe("%s/+/+/+" % (MQTT_SENSOR_PREFIX), 0)
    mqttc.subscribe("%s/+/$implementation/ota/#" % (MQTT_SENSOR_PREFIX), 0)

# on_delete_message handles deleting the topic the messages was received on.
def on_delete_message(mosq, userdata, msg):
    logging.debug("Received delete callback for topic '%s'" % msg.topic)
    if len(msg.payload) == 0:
        return
    # Publish a retain message of zero bytes.
    mqttc.publish(msg.topic, payload='', qos=1, retain=True)

def on_sensor(mosq, userdata, msg):
    if msg.topic.endswith("$ota/payload"):
        logging.info("Received OTA payload from %s" % msg.topic)
        return
    elif msg.topic.endswith("$fw/name") or msg.topic.endswith("$fw/version"):
        logging.debug("FW message %s %s" % (msg.topic, str(msg.payload)))
    elif DEBUG_SENSOR:
        logging.debug("SENSOR %s %s" % (str(msg.topic), str(msg.payload)))

    try:
        t = str(msg.topic)
        t = t[len(MQTT_SENSOR_PREFIX) + 1:]      # remove MQTT_SENSOR_PREFIX/ from begining of topic
        device, key, subkey = t.split('/')

        if key == "$fw":
            if subkey == "name":
                db[device]["fwname"] = str(msg.payload)
            if subkey == "version":
                db[device]["fwversion"] = str(msg.payload)
            return

        # Version of the Homie convention the device conforms to
        if key == "$homie":
            db[device]["homie"] = str(msg.payload)

        subtopic = "%s/%s" % (key, subkey)
        # print "DATA", device, subtopic, msg.payload

        # Homie 2.0 uptime
        if (subtopic == "$uptime/value") or (subtopic == "$stats/uptime"):
            db[device]["human_uptime"] = uptime(msg.payload)
            return

        if key == "$stats":
            if subkey == "signal":
                db[device]["signal"] = str(msg.payload)
            return

        if device not in sensors:
            sensors[device] = {}
        sensors[device][subtopic] = msg.payload
    except Exception as e:
        logging.error("Cannot extract sensor device/data: for %s: %s" % (str(msg.topic), str(e)))

def on_ota_info(mosq, userdata, msg):
    device = msg.topic.split('/')[1]
    progress = re.compile("206\s(?P<current>[0-9]+)\/(?P<all>[0-9]+)")
    reason = re.compile("[0-9]+\s(?P<reason>.*)")
    if msg.topic.endswith('status'):
        if msg.payload == "200":
            logging.info("{}: Flash has been done correctly".format(device))
        elif msg.payload == "202":
            logging.info("{}: OTA request/checksum has been accepted".format(device))
        elif msg.payload == "304":
            logging.info("{}: The current firmware is already up-to-date".format(device))
        elif msg.payload == "403":
            logging.warning("{}: OTA is not enabled".format(device))
        elif msg.payload.startswith("206"):
            if DEBUG:
                data = progress.match(msg.payload)
                logging.debug("{}: OTA Flashing: {}/{}".format(device, data.group('current'), data.group('all')))
        elif msg.payload.startswith("400"):
            data = reason.match(msg.payload)
            logging.error("{}: OTA is aborted due to error on server: {}".format(device, data.group('reason')))
        elif msg.payload.startswith("500"):
            data = reason.match(msg.payload)
            logging.error("{}: OTA is aborted due to error on client: {}".format(device, data.group('reason')))
        else:
            logging.info("{}: Unknown status: {}".format(device, msg.payload))



def on_control(mosq, userdata, msg):
    logging.debug("CONTROL %s %s" % (msg.topic, str(msg.payload)))

    try:
        t = str(msg.topic)
        t = t[len(MQTT_SENSOR_PREFIX) + 1:]      # remove MQTT_SENSOR_PREFIX/ from begining of topic

        device, key = t.split('/')
        if key.startswith('$'):                 # if key starts with '$'
            key = key[1:]                       # remove '$'

        if device not in db:
            db[device] = {}
        db[device][key] = str(msg.payload)

        if key == 'uptime':
            db[device]['human_uptime'] = uptime( db[device].get('uptime', 0) )
    except Exception as e:
        logging.error("Cannot extract control device/data: for %s: %s" % (str(msg.topic), str(e)))

def on_disconnect(mosq, userdata, rc):
    reasons = {
       '0' : 'Connection Accepted',
       '1' : 'Connection Refused: unacceptable protocol version',
       '2' : 'Connection Refused: identifier rejected',
       '3' : 'Connection Refused: server unavailable',
       '4' : 'Connection Refused: bad user name or password',
       '5' : 'Connection Refused: not authorized',
    }
    reason = reasons.get(rc, "code=%s" % rc)
    logging.debug("Disconnected: %s", reason)

def on_log(mosq, userdata, level, string):
    logging.debug(string)

if __name__ == '__main__':

    if not os.path.exists(OTA_FIRMWARE_ROOT):
        logging.error("Firmware root (%s) does not exist (or is not a directory)"% (OTA_FIRMWARE_ROOT))
        sys.exit(2)

    mqttc.on_connect = on_connect
    mqttc.on_disconnect = on_disconnect
    mqttc.on_message = on_control
    mqttc.message_callback_add("%s/+/+/+" % (MQTT_SENSOR_PREFIX), on_sensor)
    mqttc.message_callback_add("%s/+/$implementation/ota/#" % (MQTT_SENSOR_PREFIX), on_ota_info)
    # mqttc.on_log = on_log

    if MQTT_CAFILE:
        mqttc.tls_set(MQTT_CAFILE)

    if MQTT_USERNAME:
        mqttc.username_pw_set(MQTT_USERNAME, MQTT_PASSWORD)

    logging.debug("Attempting connection to MQTT broker at %s:%d..." % (MQTT_HOST, MQTT_PORT))
    try:
        mqttc.connect(MQTT_HOST, MQTT_PORT, 60)
    except Exception as e:
        logging.error("Cannot connect to MQTT broker at %s:%d: %s" % (MQTT_HOST, MQTT_PORT, str(e)))
        sys.exit(2)

    mqttc.loop_start()

    signal.signal(signal.SIGTERM, handleterm)
    atexit.register(exitus)

    try:
        run(host=OTA_HOST, port=OTA_PORT, debug=DEBUG)
    except KeyboardInterrupt:
        mqttc.loop_stop()
        mqttc.disconnect()
        sys.exit(0)
    except:
        raise