mqtt_listener.py

"""
Source written by Nathan Chen (https://github.com/nucktwillieren)
You may need to modified this file to meet your need
"""

import logging

import paho.mqtt.client as mqtt
import threading
import time
import random
import datetime
import json
from dateutil import parser
from settings import MQTT_SCOPE, MQTT_USERNAME, MQTT_PASSWORD

# TODO: what data do you want?
temperature = -1
last_updated = datetime.MINYEAR


# 當地端程式連線伺服器得到回應時，要做的動作
def on_connect(client, userdata, flags, rc):
    print("[MQTT] Connected with result code "+str(rc), flush=True)

    # 將訂閱主題寫在on_connet中
    # 如果我們失去連線或重新連線時
    # 地端程式將會重新訂閱
    client.subscribe(f"ideasky/{MQTT_SCOPE}/#")  # TODO: change the subscription if needed


# 當接收到從伺服器發送的訊息時要進行的動作
def on_message(client, userdata, msg):
    # 轉換編碼utf-8才看得懂中文
    data = msg.payload.decode('utf-8')
    print('[MQTT MSG]', msg.topic, data, flush=True)

    # TODO: parse the data
    json_data = json.loads(data)
    global temperature, last_updated
    temperature = json_data['Temperature']
    last_updated = parser.parse(json_data['Time'])


# Log
def on_log(client, userdata, level, buf):
    # print('[MQTT LOG]', level, buf)
    return


# def job(client):
#    while 1:
#        t0 = random.randint(0, 30)
#        t = datetime.datetime.now().isoformat()
#        payload = {'Temperature': t0, 'Time': t}
#        print(json.dumps(payload))
#        # 要發布的主題和內容
#        client.publish("Try/MQTT", json.dumps(payload))
#        time.sleep(5)
#


def init():
    if not MQTT_SCOPE:
        print('[MQTT] No scope specified, exit from MQTT.')
        return

    # 連線設定
    # 初始化地端程式
    client = mqtt.Client()

    # 設定連線的動作
    client.on_connect = on_connect

    # 設定接收訊息的動作
    client.on_message = on_message

    client.on_log = on_log


    # 設定登入帳號密碼
    client.username_pw_set(MQTT_USERNAME, MQTT_PASSWORD)

    # 設定連線資訊(IP, Port, 連線時間)
    print('[MQTT] Attempt to connect', flush=True)
    client.connect("ideasky.app", 1883, 60)        # TODO: change the host if needed

    # 開始連線，執行設定的動作和處理重新連線問題
    # 也可以手動使用其他loop函式來進行連接
    client.loop_start()