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MQTT can be used on various platforms. When we have server up and running, I will provide guides how to install clients on various platforms.

Installing MQTT clients

Linux

apt-get update
apt-get install openssl libssl-dev python

cd /tmp/
wget http://git.eclipse.org/c/paho/org.eclipse.paho.mqtt.python.git/snapshot/org.eclipse.paho.mqtt.python-1.1.tar.gz
tar xzf org.eclipse.paho.mqtt.python-1.1.tar.gz
cd org.eclipse.paho.mqtt.python-1.1
python setup.py install

Windows

• Install Python
• Download http://git.eclipse.org/c/paho/org.eclipse.paho.mqtt.python.git/snapshot/org.eclipse.paho.mqtt.python-1.1.tar.gz (please not, that there might be newer version available)
• Unzip, go to folder where setup.py is located and type

python setup.py install

Carambola2

Carambola 2

Carambola from 8devices has huge advantage when used as smart sensor or local sensor concentrator – it has low power consumption, integrated high power WiFi and LAN connections. Also features some GPIO pins and lot of digital sensors can be used directly.

opkg install python python-openssl pyserial

cd /tmp/
wget http://git.eclipse.org/c/paho/org.eclipse.paho.mqtt.python.git/snapshot/org.eclipse.paho.mqtt.python-1.1.tar.gz
tar xzf org.eclipse.paho.mqtt.python-1.1.tar.gz
cd org.eclipse.paho.mqtt.python-1.1
python setup.py install

Carambola can be used not only as paho client but also whole mosquitto broker can be installed. It should be enough for house or small office. For OpenWrt mosquitto sources see on mosquitto web page.

Raspberry Pi

Raspberry Pi

I have tested only Ubuntu RPi package, so installation process is the same like Linux. It has some advantage over Carambola, when bigger processing power and storage is needed. It should be better used as MQTT broker. Local broker running on Raspberry Pi can be very handy and compact IoT gateway machine, especially when fitted aluminium case I designed some time ago.

Some usage examples

Copy ca.crt certificate from mosquitto server installation to fresh directory or add a path to ca.crt file.

1. Elementary subscribe code snippet.  This code snippet will subscribe topic test and will messages to screen. Easy!

import paho.mqtt.client as paho

def on_message(clnt, userdata, msg):
	print(msg.topic+" "+str(msg.payload))

mqttc = paho.Client()
mqttc.on_message = on_message
mqttc.tls_set("ca.crt")
mqttc.connect("127.0.0.1", 8883)
mqttc.subscribe("test/#")
mqttc.loop_forever()

 2. Complementary example for publishing message on topic

import paho.mqtt.client as paho

mqttc = paho.Client()
mqttc.tls_set("ca.crt")
mqttc.connect("127.0.0.1", 8883)
mqttc.publish("test/temperature", '22.5', 0)