mqtt.py

import gc
import ujson
# from libs import ssd1306
from machine import Pin, I2C, reset
from dht import DHT11
from time import sleep_ms
from ujson import dump, load
from umqtt.simple import MQTTClient


id = '***********'
server = '***********'
port = 1111
username = '***********'
password = '***********'

led17 = Pin(17, Pin.OUT)
led18 = Pin(18, Pin.OUT)

# d = DHT11(Pin(4))
# i2c = I2C(-1, Pin(22), Pin(21)) # slc, sda
# display = ssd1306.SSD1306_I2C(128, 64, i2c)

# display.fill(0)

def writelastcfg(pin0=17, value0=0, pin1=18, value1=0):
    lastcfg = {pin0: value0, pin1: value1}
    with open('db.json', 'w') as f:
        dump(lastcfg, f)
    print('State writed successfull.')

def writelastcfg(pin0=17, value0=0, pin1=18, value1=0):
    lastcfg = {pin0: value0, pin1: value1}
    with open('db.json', 'w') as f:
        dump(lastcfg, f)
    print('State writed successfull.')

def getlastcfg():
    try:
        with open('db.json', 'r') as f:
            lastcfg = load(f)
        led17.value(lastcfg[17])
        led18.value(lastcfg[18])
        print('Last config applied successfull.')
    except:
        led17.value(0)
        led18.value(0)
        print('Some error to get last states, state 0 applied.')


def convert_str_dict(str):
    try:
        a = str.replace("'", "\"")
        return ujson.loads(a)
    except:
        print('Fail to convert string {} to dict.'.format(str))


def flash_led_2():
    led = Pin(2, Pin.OUT, value=1)
    led.value(0)
    sleep_ms(50)
    led.value(1)
    sleep_ms(50)


# def send_dht(c):
#     try:
#         d.measure()
#         data = {'temperature': d.temperature(), 'humidity': d.humidity()}
#         sleep_ms(1000)
#         display.fill(0)
#         display.text('T: {}, H: {}'.format(d.temperature(), d.humidity()), 0, 10)
#         c.publish('esp32/dht11', '{}'.format(data))
#     except OSError as e:
#         print('Some error to read DHT11 data: {}'.format(e))


# receive all notifications from topic
def sub_cb(topic, msg):

    gc.collect()
    getlastcfg()

    # display.fill(0)

    msg = msg.decode('utf-8')
    topic = topic.decode('utf-8')
    msg = convert_str_dict(msg)
    led = Pin(msg['pin'], Pin.OUT)
    print('Received from topic: {}, with message: {}!'.format(topic, msg))
    # display.text('T: {}!'.format(topic), 0, 20)

    flash_led_2()

    if msg['state'] == 'toggle':
        state = 1-led.value()
        led.value(state)
        if msg['pin'] == 17:
            writelastcfg(pin0=17, value0=state, pin1=18, value1=led18.value())
        elif msg['pin'] == 18:
            writelastcfg(pin0=17, value0=led17.value(), pin1=18, value1=state)
        print('Changing state of pin {} to {}'.format(msg['pin'], state))
        # display.text('Pin {} to {}'.format(msg['pin'], value), 0, 30)

    elif msg['state'] is 0 or msg['state'] is 1:
        value = int(msg['state'])
        led.value(value)
        if msg['pin'] == 17:
            writelastcfg(pin0=17, value0=value, pin1=18, value1=led18.value())
        elif msg['pin'] == 18:
            writelastcfg(pin0=17, value0=led17.value(), pin1=18, value1=value)
        print('Changing state of pin {} to {}'.format(msg['pin'], value))
        # display.text('Pin {} to {}'.format(msg['pin'], value), 0, 30)


# connect with mqtt client
def main(id, server, port, username, password):
    c = MQTTClient(id, server, port, username, password)
    c.set_callback(sub_cb)
    c.connect()
    c.subscribe('esp32/leds')
    print('Connected!')
    # display.text('Connected!', 0, 10)
    sleep_ms(1000)
    # display.fill(0)
    # display.show()

    try:
        while True:
            # c.wait_msg()
            c.check_msg()
            gc.collect()
            # send_dht(c)
            # display.show()
    except OSError as e:
        print('Error: {}'.format(e))
        print('Failed to connect to MQTT broker. Reconnecting...')
        sleep_ms(5000)
        reset()
    finally:
        print('Disconnecting...')
        c.disconnect()


# function called in main.py
def connect():
    getlastcfg()
    main(id, server, port, username, password)