Python MQTT 最簡單例程搭建

• MQTT 不是普通的 client server 模型，他還加了一個 代理者。

    根據劍鋒的提示，先下載了 paho-mqtt 模塊， ubuntu 14.04 上下載方法如下：
    sudo apt-get install  python-pip
    sudo pip install paho-mqtt
    source paho-mqtt/bin/activate
    sudo apt-get install python-virtualenv
    virtualenv paho-mqtt

• 下載 broker 代理

    參考： http://www.steves-internet-guide.com/install-mosquitto-linux/#install-test
    sudo apt-add-repository ppa:mosquitto-dev/mosquitto-ppa
     sudo apt-get update
     sudo apt-get install mosquitto
     sudo apt-get install mosquitto-clients
     sudo server mosquitto start
    mosquitto -v
    // 帶調試信息的啟動

• server 代碼編寫

    import paho.mqtt.client as mqtt

    def on_connect(client, userdata, flags, rc):
        print("Connected with result code "+str(rc))
        client.subscribe("chat")

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

    client = mqtt.Client()
    client.on_connect = on_connect
    client.on_message = on_message
    client.connect("127.0.0.1", 1883, 60)
    client.loop_forever()

• client 代碼編寫

    import paho.mqtt.client as mqtt

    HOST = "127.0.0.1"
    PORT = 1883

    def test():
        client = mqtt.Client()
        client.connect(HOST, PORT, 60)
        client.publish("chat","hello chenfulin",2)
        client.loop_forever()

    if __name__ == '__main__':
        test()

• 啟動

    python server.py
    python client.py