amqtt/hbmqtt/client.py

431 wiersze
16 KiB
Python

# Copyright (c) 2015 Nicolas JOUANIN
#
# See the file license.txt for copying permission.
import logging
import ssl
from urllib.parse import urlparse, urlunparse
from hbmqtt.utils import not_in_dict_or_none
from hbmqtt.session import Session
from hbmqtt.mqtt.connack import *
from hbmqtt.mqtt.connect import *
from hbmqtt.mqtt.protocol.client_handler import ClientProtocolHandler
from hbmqtt.adapters import StreamReaderAdapter, StreamWriterAdapter, WebSocketsReader, WebSocketsWriter
from hbmqtt.plugins.manager import PluginManager, BaseContext
from hbmqtt.mqtt.protocol.handler import EVENT_MQTT_PACKET_SENT, EVENT_MQTT_PACKET_RECEIVED, ProtocolHandlerException
from hbmqtt.mqtt.constants import *
import websockets
from websockets.uri import InvalidURI
from websockets.handshake import InvalidHandshake
from collections import deque
import sys
if sys.version_info < (3, 5):
from asyncio import async as ensure_future
else:
from asyncio import ensure_future
_defaults = {
'keep_alive': 10,
'ping_delay': 1,
'default_qos': 0,
'default_retain': False,
'auto_reconnect': True,
'reconnect_max_interval': 10,
'reconnect_retries': 2,
}
class ClientException(BaseException):
pass
class ConnectException(ClientException):
pass
class ClientContext(BaseContext):
"""
ClientContext is used as the context passed to plugins interacting with the client.
It act as an adapter to client services from plugins
"""
def __init__(self):
super().__init__()
self.config = None
base_logger = logging.getLogger(__name__)
def mqtt_connected(func):
"""
MQTTClient coroutines decorator which will wait until connection before calling the decorated method.
:param func: coroutine to be called once connected
:return: coroutine result
"""
@asyncio.coroutine
def wrapper(self, *args, **kwargs):
if not self._connected_state.is_set():
base_logger.warning("Client not connected, waiting for it")
yield from self._connected_state.wait()
return (yield from func(self, *args, **kwargs))
return wrapper
class MQTTClient:
def __init__(self, client_id=None, config=None, loop=None):
"""
:param config: Example yaml config
broker:
uri: mqtt:username@password//localhost:1883/
cafile: somefile.cert #Server authority file
capath: /some/path # certficate file path
cadata: certificate as string data
keep_alive: 60
cleansession: true
will:
retain: false
topic: some/topic
message: Will message
qos: 0
default_qos: 0
default_retain: false
topics:
a/b:
qos: 2
retain: true
:param loop:
:return:
"""
self.logger = logging.getLogger(__name__)
self.config = _defaults
if config is not None:
self.config.update(config)
if client_id is not None:
self.client_id = client_id
else:
from hbmqtt.utils import gen_client_id
self.client_id = gen_client_id()
self.logger.debug("Using generated client ID : %s" % self.client_id)
if loop is not None:
self._loop = loop
else:
self._loop = asyncio.get_event_loop()
self.session = None
self._handler = None
self._disconnect_task = None
self._connected_state = asyncio.Event()
# Init plugins manager
context = ClientContext()
context.config = self.config
self.plugins_manager = PluginManager('hbmqtt.client.plugins', context)
self.client_tasks = deque()
@asyncio.coroutine
def connect(self,
uri=None,
cleansession=None,
cafile=None,
capath=None,
cadata=None):
"""
Connect to a remote broker
:param uri: Broker URI connection, conforming to `MQTT URI scheme <https://github.com/mqtt/mqtt.github.io/wiki/URI-Scheme>`_.
:param cleansession: MQTT CONNECT clean session flaf
:param cafile: server certificate authority file
:return:
"""
self.session = self._initsession(uri, cleansession, cafile, capath, cadata)
self.logger.debug("Connect to: %s" % uri)
try:
return (yield from self._do_connect())
except BaseException as be:
self.logger.warning("Connection failed: %r" % be)
auto_reconnect = self.config.get('auto_reconnect', False)
if not auto_reconnect:
raise
else:
return (yield from self.reconnect())
@mqtt_connected
@asyncio.coroutine
def disconnect(self):
if self.session.transitions.is_connected():
if not self._disconnect_task.done():
self._disconnect_task.cancel()
yield from self._handler.mqtt_disconnect()
self._connected_state.clear()
yield from self._handler.stop()
self.session.transitions.disconnect()
else:
self.logger.warn("Client session is not currently connected, ignoring call")
@asyncio.coroutine
def reconnect(self, cleansession=None):
if self.session.transitions.is_connected():
self.logger.warn("Client already connected")
return CONNECTION_ACCEPTED
if cleansession:
self.session.clean_session = cleansession
self.logger.debug("Reconnecting with session parameters: %s" % self.session)
reconnect_max_interval = self.config.get('reconnect_max_interval', 10)
reconnect_retries = self.config.get('reconnect_retries', 5)
nb_attempt = 1
yield from asyncio.sleep(1, loop=self._loop)
while True:
try:
self.logger.debug("Reconnect attempt %d ..." % nb_attempt)
return (yield from self._do_connect())
except BaseException as e:
self.logger.warning("Reconnection attempt failed: %r" % e)
if nb_attempt > reconnect_retries:
self.logger.error("Maximum number of connection attempts reached. Reconnection aborted")
raise ConnectException("Too many connection attempts failed")
exp = 2 ** nb_attempt
delay = exp if exp < reconnect_max_interval else reconnect_max_interval
self.logger.debug("Waiting %d second before next attempt" % delay)
yield from asyncio.sleep(delay, loop=self._loop)
nb_attempt += 1
@asyncio.coroutine
def _do_connect(self):
return_code = yield from self._connect_coro()
self._disconnect_task = ensure_future(self.handle_connection_close(), loop=self._loop)
return return_code
@mqtt_connected
@asyncio.coroutine
def ping(self):
"""
Send a MQTT ping request and wait for response
:return: None
"""
if self.session.transitions.is_connected():
yield from self._handler.mqtt_ping()
else:
self.logger.warn("MQTT PING request incompatible with current session state '%s'" %
self.session.transitions.state)
@mqtt_connected
@asyncio.coroutine
def publish(self, topic, message, qos=None, retain=None):
def get_retain_and_qos():
if qos:
assert qos in (QOS_0, QOS_1, QOS_2)
_qos = qos
else:
_qos = self.config['default_qos']
try:
_qos = self.config['topics'][topic]['qos']
except KeyError:
pass
if retain:
_retain = retain
else:
_retain = self.config['default_retain']
try:
_retain = self.config['topics'][topic]['retain']
except KeyError:
pass
return _qos, _retain
(app_qos, app_retain) = get_retain_and_qos()
return (yield from self._handler.mqtt_publish(topic, message, app_qos, app_retain))
@mqtt_connected
@asyncio.coroutine
def subscribe(self, topics):
return (yield from self._handler.mqtt_subscribe(topics, self.session.next_packet_id))
@mqtt_connected
@asyncio.coroutine
def unsubscribe(self, topics):
yield from self._handler.mqtt_unsubscribe(topics, self.session.next_packet_id)
@asyncio.coroutine
def deliver_message(self, timeout=None):
deliver_task = ensure_future(self._handler.mqtt_deliver_next_message(), loop=self._loop)
self.client_tasks.append(deliver_task)
self.logger.debug("Waiting message delivery")
yield from asyncio.wait([deliver_task], loop=self._loop, return_when=asyncio.FIRST_EXCEPTION, timeout=timeout)
if deliver_task.exception():
raise deliver_task.exception()
self.client_tasks.pop()
return deliver_task.result()
@asyncio.coroutine
def _connect_coro(self):
kwargs = dict()
# Decode URI attributes
uri_attributes = urlparse(self.session.broker_uri)
scheme = uri_attributes.scheme
secure = True if scheme in ('mqtts', 'wss') else False
self.session.username = uri_attributes.username
self.session.password = uri_attributes.password
self.session.remote_address = uri_attributes.hostname
self.session.remote_port = uri_attributes.port
if scheme in ('mqtt', 'mqtts') and not self.session.remote_port:
self.session.remote_port = 8883 if scheme == 'mqtts' else 1883
if scheme in ('ws', 'wss') and not self.session.remote_port:
self.session.remote_port = 443 if scheme == 'wss' else 80
if scheme in ('ws', 'wss'):
# Rewrite URI to conform to https://tools.ietf.org/html/rfc6455#section-3
uri = (scheme, self.session.remote_address + ":" + str(self.session.remote_port), uri_attributes[2],
uri_attributes[3], uri_attributes[4], uri_attributes[5])
self.session.broker_uri = urlunparse(uri)
# Init protocol handler
#if not self._handler:
self._handler = ClientProtocolHandler(self.plugins_manager, loop=self._loop)
if secure:
if self.session.cafile is None or self.session.cafile == '':
self.logger.warn("TLS connection can't be estabilshed, no certificate file (.cert) given")
raise ClientException("TLS connection can't be estabilshed, no certificate file (.cert) given")
sc = ssl.create_default_context(
ssl.Purpose.SERVER_AUTH,
cafile=self.session.cafile,
capath=self.session.capath,
cadata=self.session.cadata)
if 'certfile' in self.config and 'keyfile' in self.config:
sc.load_cert_chain(self.config['certfile'], self.config['keyfile'])
kwargs['ssl'] = sc
try:
reader = None
writer = None
self._connected_state.clear()
# Open connection
if scheme in ('mqtt', 'mqtts'):
conn_reader, conn_writer = \
yield from asyncio.open_connection(
self.session.remote_address,
self.session.remote_port, loop=self._loop, **kwargs)
reader = StreamReaderAdapter(conn_reader)
writer = StreamWriterAdapter(conn_writer)
elif scheme in ('ws', 'wss'):
websocket = yield from websockets.connect(
self.session.broker_uri,
subprotocols=['mqtt'],
loop=self._loop,
**kwargs)
reader = WebSocketsReader(websocket)
writer = WebSocketsWriter(websocket)
# Start MQTT protocol
self._handler.attach(self.session, reader, writer)
return_code = yield from self._handler.mqtt_connect()
if return_code is not CONNECTION_ACCEPTED:
self.session.transitions.disconnect()
self.logger.warning("Connection rejected with code '%s'" % return_code)
exc = ConnectException("Connection rejected by broker")
exc.return_code = return_code
raise exc
else:
# Handle MQTT protocol
yield from self._handler.start()
self.session.transitions.connect()
self._connected_state.set()
self.logger.debug("connected to %s:%s" % (self.session.remote_address, self.session.remote_port))
return return_code
except InvalidURI as iuri:
self.logger.warn("connection failed: invalid URI '%s'" % self.session.broker_uri)
self.session.transitions.disconnect()
raise ConnectException("connection failed: invalid URI '%s'" % self.session.broker_uri, iuri)
except InvalidHandshake as ihs:
self.logger.warn("connection failed: invalid websocket handshake")
self.session.transitions.disconnect()
raise ConnectException("connection failed: invalid websocket handshake", ihs)
except (ProtocolHandlerException, ConnectionError, OSError) as e:
self.logger.warn("MQTT connection failed: %r" % e)
self.session.transitions.disconnect()
raise ConnectException(e)
@asyncio.coroutine
def handle_connection_close(self):
self.logger.debug("Watch broker disconnection")
# Wait for disconnection from broker (like connection lost)
yield from self._handler.wait_disconnect()
self.logger.warning("Disconnected from broker")
# Block client API
self._connected_state.clear()
# stop an clean handler
yield from self._handler.stop()
self._handler.detach()
self.session.transitions.disconnect()
if self.config.get('auto_reconnect', False):
# Try reconnection
self.logger.debug("Auto-reconnecting")
try:
yield from self.reconnect()
except ConnectException:
# Cancel client pending tasks
while self.client_tasks:
self.client_tasks.popleft().set_exception(ClientException("Connection lost"))
else:
# Cancel client pending tasks
while self.client_tasks:
self.client_tasks.popleft().set_exception(ClientException("Connection lost"))
def _initsession(
self,
uri=None,
cleansession=None,
cafile=None,
capath=None,
cadata=None) -> Session:
# Load config
broker_conf = self.config.get('broker', dict()).copy()
if uri:
broker_conf['uri'] = uri
if cafile:
broker_conf['cafile'] = cafile
elif 'cafile' not in broker_conf:
broker_conf['cafile'] = None
if capath:
broker_conf['capath'] = capath
elif 'capath' not in broker_conf:
broker_conf['capath'] = None
if cadata:
broker_conf['cadata'] = cadata
elif 'cadata' not in broker_conf:
broker_conf['cadata'] = None
if cleansession is not None:
broker_conf['cleansession'] = cleansession
for key in ['uri']:
if not_in_dict_or_none(broker_conf, key):
raise ClientException("Missing connection parameter '%s'" % key)
s = Session()
s.broker_uri = uri
s.client_id = self.client_id
s.cafile = broker_conf['cafile']
s.capath = broker_conf['capath']
s.cadata = broker_conf['cadata']
if cleansession is not None:
s.clean_session = cleansession
else:
s.clean_session = self.config.get('cleansession', True)
s.keep_alive = self.config['keep_alive'] - self.config['ping_delay']
if 'will' in self.config:
s.will_flag = True
s.will_retain = self.config['will']['retain']
s.will_topic = self.config['will']['topic']
s.will_message = self.config['will']['message']
s.will_qos = self.config['will']['qos']
else:
s.will_flag = False
s.will_retain = False
s.will_topic = None
s.will_message = None
return s