alefo

Code: Alles auswählen

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



#import paho.mqtt.publish as publish

"""
This module provides some helper functions to allow straightforward publishing
of messages in a one-shot manner. In other words, they are useful for the
situation where you have a single/multiple messages you want to publish to a
broker, then disconnect and nothing else is required.
"""

import paho.mqtt.client as paho


def _do_publish(client):
"""Internal function"""

message = client._userdata.pop()

if isinstance(message, dict):
client.publish(**message)
elif isinstance(message, tuple):
client.publish(*message)
else:
raise ValueError('message must be a dict or a tuple')


def _on_connect(client, userdata, flags, rc):
"""Internal callback"""
#pylint: disable=invalid-name, unused-argument

if rc == 0:
if len(userdata) > 0:
_do_publish(client)
else:
raise mqtt.MQTTException(paho.connack_string(rc))


def _on_publish(client, userdata, mid):
"""Internal callback"""
#pylint: disable=unused-argument

if len(userdata) == 0:
client.disconnect()
else:
_do_publish(client)


def multiple(msgs, hostname="localhost", port=1883, client_id="", keepalive=60,
will=None, auth=None, tls=None, protocol=paho.MQTTv311,
transport="tcp"):
"""Publish multiple messages to a broker, then disconnect cleanly.

This function creates an MQTT client, connects to a broker and publishes a
list of messages. Once the messages have been delivered, it disconnects
cleanly from the broker.

msgs : a list of messages to publish. Each message is either a dict or a
tuple.

If a dict, only the topic must be present. Default values will be
used for any missing arguments. The dict must be of the form:

msg = {'topic':"<topic>", 'payload':"<payload>", 'qos':<qos>,
'retain':<retain>}
topic must be present and may not be empty.
If payload is "", None or not present then a zero length payload
will be published.
If qos is not present, the default of 0 is used.
If retain is not present, the default of False is used.

If a tuple, then it must be of the form:
("<topic>", "<payload>", qos, retain)

hostname : a string containing the address of the broker to connect to.
Defaults to localhost.

port : the port to connect to the broker on. Defaults to 1883.

client_id : the MQTT client id to use. If "" or None, the Paho library will
generate a client id automatically.

keepalive : the keepalive timeout value for the client. Defaults to 60
seconds.

will : a dict containing will parameters for the client: will = {'topic':
"<topic>", 'payload':"<payload">, 'qos':<qos>, 'retain':<retain>}.
Topic is required, all other parameters are optional and will
default to None, 0 and False respectively.
Defaults to None, which indicates no will should be used.

auth : a dict containing authentication parameters for the client:
auth = {'username':"<username>", 'password':"<password>"}
Username is required, password is optional and will default to None
if not provided.
Defaults to None, which indicates no authentication is to be used.

tls : a dict containing TLS configuration parameters for the client:
dict = {'ca_certs':"<ca_certs>", 'certfile':"<certfile>",
'keyfile':"<keyfile>", 'tls_version':"<tls_version>",
'ciphers':"<ciphers">}
ca_certs is required, all other parameters are optional and will
default to None if not provided, which results in the client using
the default behaviour - see the paho.mqtt.client documentation.
Alternatively, tls input can be an SSLContext object, which will be
processed using the tls_set_context method.
Defaults to None, which indicates that TLS should not be used.

transport : set to "tcp" to use the default setting of transport which is
raw TCP. Set to "websockets" to use WebSockets as the transport.
"""

if not isinstance(msgs, list):
raise ValueError('msgs must be a list')

client = paho.Client(client_id=client_id,
userdata=msgs, protocol=protocol, transport=transport)

client.on_publish = _on_publish
client.on_connect = _on_connect

if auth:
username = auth.get('username')
if username:
password = auth.get('password')
client.username_pw_set(username, password)
else:
raise KeyError("The 'username' key was not found, this is "
"required for auth")

if will is not None:
client.will_set(**will)

if tls is not None:
if isinstance(tls, dict):
client.tls_set(**tls)
else:
# Assume input is SSLContext object
client.tls_set_context(tls)

client.connect(hostname, port, keepalive)
client.loop_forever()


def single(topic, payload=None, qos=0, retain=False, hostname="localhost",
port=1883, client_id="", keepalive=60, will=None, auth=None,
tls=None, protocol=paho.MQTTv311, transport="tcp"):
"""Publish a single message to a broker, then disconnect cleanly.

This function creates an MQTT client, connects to a broker and publishes a
single message. Once the message has been delivered, it disconnects cleanly
from the broker.

topic : the only required argument must be the topic string to which the
payload will be published.

payload : the payload to be published. If "" or None, a zero length payload
will be published.

qos : the qos to use when publishing, default to 0.

retain : set the message to be retained (True) or not (False).

hostname : a string containing the address of the broker to connect to.
Defaults to localhost.

port : the port to connect to the broker on. Defaults to 1883.

client_id : the MQTT client id to use. If "" or None, the Paho library will
generate a client id automatically.

keepalive : the keepalive timeout value for the client. Defaults to 60
seconds.

will : a dict containing will parameters for the client: will = {'topic':
"<topic>", 'payload':"<payload">, 'qos':<qos>, 'retain':<retain>}.
Topic is required, all other parameters are optional and will
default to None, 0 and False respectively.
Defaults to None, which indicates no will should be used.

auth : a dict containing authentication parameters for the client:
auth = {'username':"<username>", 'password':"<password>"}
Username is required, password is optional and will default to None
if not provided.
Defaults to None, which indicates no authentication is to be used.

tls : a dict containing TLS configuration parameters for the client:
dict = {'ca_certs':"<ca_certs>", 'certfile':"<certfile>",
'keyfile':"<keyfile>", 'tls_version':"<tls_version>",
'ciphers':"<ciphers">}
ca_certs is required, all other parameters are optional and will
default to None if not provided, which results in the client using
the default behaviour - see the paho.mqtt.client documentation.
Defaults to None, which indicates that TLS should not be used.
Alternatively, tls input can be an SSLContext object, which will be
processed using the tls_set_context method.

transport : set to "tcp" to use the default setting of transport which is
raw TCP. Set to "websockets" to use WebSockets as the transport.
"""

msg = {'topic':topic, 'payload':payload, 'qos':qos, 'retain':retain}

multiple([msg], hostname, port, client_id, keepalive, will, auth, tls,
protocol, transport)

#######################################################################

single("XXX", "hallo von lambda aws", hostname="XXX")