import io
import json
import os
import threading
from typing import Any, Optional, IO
from platypush.config import Config
from platypush.message import Message
from platypush.plugins import Plugin, action
[docs]class MqttPlugin(Plugin):
"""
This plugin allows you to send custom message to a message queue compatible
with the MQTT protocol, see https://mqtt.org/
Requires:
* **paho-mqtt** (``pip install paho-mqtt``)
"""
[docs] def __init__(
self,
host=None,
port=1883,
tls_cafile=None,
tls_certfile=None,
tls_keyfile=None,
tls_version=None,
tls_ciphers=None,
tls_insecure=False,
username=None,
password=None,
client_id=None,
timeout=None,
**kwargs,
):
"""
:param host: If set, MQTT messages will by default routed to this host
unless overridden in `send_message` (default: None)
:type host: str
:param port: If a default host is set, specify the listen port
(default: 1883)
:type port: int
:param tls_cafile: If a default host is set and requires TLS/SSL,
specify the certificate authority file (default: None)
:type tls_cafile: str
:param tls_certfile: If a default host is set and requires TLS/SSL,
specify the certificate file (default: None)
:type tls_certfile: str
:param tls_keyfile: If a default host is set and requires TLS/SSL,
specify the key file (default: None)
:type tls_keyfile: str
:param tls_version: If TLS/SSL is enabled on the MQTT server and it
requires a certain TLS version, specify it here (default: None).
Supported versions: ``tls`` (automatic), ``tlsv1``, ``tlsv1.1``,
``tlsv1.2``.
:type tls_version: str
:param tls_ciphers: If a default host is set and requires TLS/SSL,
specify the supported ciphers (default: None)
:type tls_ciphers: str
:param tls_insecure: Set to True to ignore TLS insecure warnings
(default: False).
:type tls_insecure: bool
:param username: If a default host is set and requires user
authentication, specify the username ciphers (default: None)
:type username: str
:param password: If a default host is set and requires user
authentication, specify the password ciphers (default: None)
:type password: str
:param client_id: ID used to identify the client on the MQTT server
(default: None). If None is specified then
``Config.get('device_id')`` will be used.
:type client_id: str
:param timeout: Client timeout in seconds (default: None).
:type timeout: int
"""
super().__init__(**kwargs)
self.host = host
self.port = port
self.username = username
self.password = password
self.client_id = client_id or Config.get('device_id')
self.tls_cafile = self._expandpath(tls_cafile) if tls_cafile else None
self.tls_certfile = self._expandpath(tls_certfile) if tls_certfile else None
self.tls_keyfile = self._expandpath(tls_keyfile) if tls_keyfile else None
self.tls_version = self.get_tls_version(tls_version)
self.tls_insecure = tls_insecure
self.tls_ciphers = tls_ciphers
self.timeout = timeout
@staticmethod
def get_tls_version(version: Optional[str] = None):
import ssl
if not version:
return None
if isinstance(version, type(ssl.PROTOCOL_TLS)):
return version
if isinstance(version, str):
version = version.lower()
if version == 'tls':
return ssl.PROTOCOL_TLS
if version == 'tlsv1':
return ssl.PROTOCOL_TLSv1
if version == 'tlsv1.1':
return ssl.PROTOCOL_TLSv1_1
if version == 'tlsv1.2':
return ssl.PROTOCOL_TLSv1_2
assert f'Unrecognized TLS version: {version}'
def _mqtt_args(self, **kwargs):
return {
'host': kwargs.get('host', self.host),
'port': kwargs.get('port', self.port),
'timeout': kwargs.get('timeout', self.timeout),
'tls_certfile': kwargs.get('tls_certfile', self.tls_certfile),
'tls_keyfile': kwargs.get('tls_keyfile', self.tls_keyfile),
'tls_version': kwargs.get('tls_version', self.tls_version),
'tls_ciphers': kwargs.get('tls_ciphers', self.tls_ciphers),
'username': kwargs.get('username', self.username),
'password': kwargs.get('password', self.password),
}
@staticmethod
def _expandpath(path: Optional[str] = None) -> Optional[str]:
return os.path.abspath(os.path.expanduser(path)) if path else None
def _get_client(
self,
tls_cafile: Optional[str] = None,
tls_certfile: Optional[str] = None,
tls_keyfile: Optional[str] = None,
tls_version: Optional[str] = None,
tls_ciphers: Optional[str] = None,
tls_insecure: Optional[bool] = None,
username: Optional[str] = None,
password: Optional[str] = None,
):
from paho.mqtt.client import Client
tls_cafile = self._expandpath(tls_cafile or self.tls_cafile)
tls_certfile = self._expandpath(tls_certfile or self.tls_certfile)
tls_keyfile = self._expandpath(tls_keyfile or self.tls_keyfile)
tls_ciphers = tls_ciphers or self.tls_ciphers
username = username or self.username
password = password or self.password
tls_version = tls_version or self.tls_version # type: ignore[reportGeneralTypeIssues]
if tls_version:
tls_version = self.get_tls_version(tls_version) # type: ignore[reportGeneralTypeIssues]
if tls_insecure is None:
tls_insecure = self.tls_insecure
client = Client()
if username and password:
client.username_pw_set(username, password)
if tls_cafile:
client.tls_set(
ca_certs=tls_cafile,
certfile=tls_certfile,
keyfile=tls_keyfile,
tls_version=tls_version, # type: ignore[reportGeneralTypeIssues]
ciphers=tls_ciphers,
)
client.tls_insecure_set(tls_insecure)
return client
[docs] @action
def publish(
self,
topic: str,
msg: Any,
host: Optional[str] = None,
port: Optional[int] = None,
reply_topic: Optional[str] = None,
timeout: int = 60,
tls_cafile: Optional[str] = None,
tls_certfile: Optional[str] = None,
tls_keyfile: Optional[str] = None,
tls_version: Optional[str] = None,
tls_ciphers: Optional[str] = None,
tls_insecure: Optional[bool] = None,
username: Optional[str] = None,
password: Optional[str] = None,
qos: int = 0,
):
"""
Sends a message to a topic.
:param topic: Topic/channel where the message will be delivered
:param msg: Message to be sent. It can be a list, a dict, or a Message
object.
:param host: MQTT broker hostname/IP (default: default host configured
on the plugin).
:param port: MQTT broker port (default: default port configured on the
plugin).
:param reply_topic: If a ``reply_topic`` is specified, then the action
will wait for a response on this topic.
:param timeout: If ``reply_topic`` is set, use this parameter to
specify the maximum amount of time to wait for a response (default:
60 seconds).
:param tls_cafile: If TLS/SSL is enabled on the MQTT server and the
certificate requires a certificate authority to authenticate it,
`ssl_cafile` will point to the provided ca.crt file (default:
None).
:param tls_certfile: If TLS/SSL is enabled on the MQTT server and a
client certificate it required, specify it here (default: None).
:param tls_keyfile: If TLS/SSL is enabled on the MQTT server and a
client certificate key it required, specify it here (default:
None).
:param tls_version: If TLS/SSL is enabled on the MQTT server and it
requires a certain TLS version, specify it here (default: None).
Supported versions: ``tls`` (automatic), ``tlsv1``, ``tlsv1.1``,
``tlsv1.2``.
:param tls_insecure: Set to True to ignore TLS insecure warnings
(default: False).
:param tls_ciphers: If TLS/SSL is enabled on the MQTT server and an
explicit list of supported ciphers is required, specify it here
(default: None).
:param username: Specify it if the MQTT server requires authentication
(default: None).
:param password: Specify it if the MQTT server requires authentication
(default: None).
:param qos: Quality of Service (_QoS_) for the message - see `MQTT QoS
<https://assetwolf.com/learn/mqtt-qos-understanding-quality-of-service>`_
(default: 0).
"""
response_buffer = io.BytesIO()
client = None
try:
# Try to parse it as a platypush message or dump it to JSON from a dict/list
if isinstance(msg, (dict, list)):
msg = json.dumps(msg)
try:
msg = Message.build(json.loads(msg))
except Exception as e:
self.logger.debug('Not a valid JSON: %s', e)
host = host or self.host
port = port or self.port or 1883
assert host, 'No host specified'
client = self._get_client(
tls_cafile=tls_cafile,
tls_certfile=tls_certfile,
tls_keyfile=tls_keyfile,
tls_version=tls_version,
tls_ciphers=tls_ciphers,
tls_insecure=tls_insecure,
username=username,
password=password,
)
client.connect(host, port, keepalive=timeout)
response_received = threading.Event()
if reply_topic:
client.on_message = self._response_callback(
reply_topic=reply_topic,
event=response_received,
buffer=response_buffer,
)
client.subscribe(reply_topic)
client.publish(topic, str(msg), qos=qos)
if not reply_topic:
return
client.loop_start()
ok = response_received.wait(timeout=timeout)
if not ok:
raise TimeoutError('Response timed out')
return response_buffer.getvalue()
finally:
response_buffer.close()
if client:
try:
client.loop_stop()
except Exception as e:
self.logger.warning('Could not stop client loop: %s', e)
client.disconnect()
@staticmethod
def _response_callback(reply_topic: str, event: threading.Event, buffer: IO[bytes]):
def on_message(client, _, msg):
if msg.topic != reply_topic:
return
buffer.write(msg.payload)
client.loop_stop()
event.set()
return on_message
[docs] @action
def send_message(self, *args, **kwargs):
"""
Alias for :meth:`platypush.plugins.mqtt.MqttPlugin.publish`.
"""
return self.publish(*args, **kwargs)
# vim:sw=4:ts=4:et:
