python mqtt 客戶端實現
阿新 • • 發佈:2019-02-14
安裝paho-mqtt
pip install paho-mqtt -i http://pypi.douban.com/simple --trusted-host pypi.douban.com
python訊息收發實現
import paho.mqtt.client as mqtt from multiprocessing import Process import camera_person_num MQTTHOST = "172.19.4.4" MQTTPORT = 1883 mqttClient = mqtt.Client() # 連線MQTT伺服器 def on_mqtt_connect(): mqttClient.connect(MQTTHOST, MQTTPORT, 60) mqttClient.loop_start() # 訊息處理函式 def on_message_come(lient, userdata, msg): print(msg.topic + ":" + str(msg.payload.decode("utf-8"))) # 訊息處理開啟多程序 p = Process(target=talk, args=("/camera/person/num/result", msg.payload.decode("utf-8"))) p.start() # subscribe 訊息訂閱 def on_subscribe(): mqttClient.subscribe("test", 1) # 主題為"test" mqttClient.on_message = on_message_come # 訊息到來處理函式 # publish 訊息釋出 def on_publish(topic, msg, qos): mqttClient.publish(topic, msg, qos); # 多程序中釋出訊息需要重新初始化mqttClient def talk(topic, msg): cameraPsersonNum = camera_person_num.CameraPsersonNum(msg) t_max, t_mean = cameraPsersonNum.personNum() mqttClient = mqtt.Client() mqttClient.connect(MQTTHOST, MQTTPORT, 60) mqttClient.loop_start() mqttClient.publish(topic, '{"max":' + str(t_max) + ',"mean:"' + str(t_mean) + '}', 1) def main(): on_mqtt_connect() on_subscribe() while True: pass if __name__ == '__main__': main()