在 paho-mqtt 中使用多个循环

Question

I am currently working on a project in which I use Paho-MQTT. In my code I have started a loop_forever in order to read messages from certain topics. The problem that is that I want to send messages with a certain delay between them to channels. Usually 'time.sleep(4)' works to add delay. For some reason this doesn't seem to work in my code now. Are there other ways to add delay in the code in this situation?

This is the python code I currently have:

import time
import threading
import random
from flask import Flask, request
import paho.mqtt.client as mqtt
import socket

app = Flask(__name__)

# GLOBAL VARIABLES
game = "none"
button1 = "off"
button2 = "off"
button3 = "off"
button4 = "off"

score_team_blue = 0
score_team_red = 0

# turn on all led's mqqt


def on_all():
    for i in range(1, 5):
        client.publish(str(i), "0")
        time.sleep(1)
        client.publish(str(i), "off")



# MQQT CLIENT


def on_message(client, userdata, message):
    global game
    # print topic and message
    topic = message.topic
    message = message.payload.decode("utf-8")
    print(f"Topic: {topic}, Message: {message}")
    if topic == "games":
        if message == "memory":
            game = "memory"
            print("memory")
        elif message == "redblue":
            game = "redblue"
            print("redblue")
            redvsblue()
        elif message == "zen":
            game = "zen"
            print("zen")
        elif message == "minesweepr":
            game = "minesweepr"
            print("minesweepr")
    if topic == "buttons":
        if message == "1":
            # test_first_led()
            button1 = "on"
        elif message == "2":
            button2 = "on"
        elif message == "3":
            button3 = "on"
        elif message == "4":
            button4 = "on"

        # if game == "memory":
        #     # Do read button stuff voor memory
        #     print("memory button incomming")
        # elif game == "redblue":
        #     # Do read button stuff voor redblue
        #     print("red vs blue button incomming")
        # elif game == "zen":
        #     # Do read button stuff voor zen
        #     print("zen button incomming")
        # elif game == "minesweepr":
        #     # Do read button stuff voor minesweepr
        #     print("minesweeper button incomming")

def redvsblue():
    print('red vs blue')
    for i in range(1, 5):
        client.publish(str(i), "0")
        time.sleep(1)
        client.publish(str(i), "off")

client = mqtt.Client()
client.connect("127.0.0.1", 1883)
client.on_message = on_message
# MQTT CODE to send to the web server
# Subscribe to the topic "game"
client.subscribe("games")
client.subscribe("buttons")
client.loop_forever()

while True:
    print("Starting server")
    app.run(debug=False)

Answer 1

loop_forever() is a blocking call, it never returns.

You can use loop_start() which will run the MQTT client.network look on a separate thread in the background.

Please check the Paho docs for different loop options:

https://www.eclipse.org/paho/index.php?page=clients/python/docs/index.php.network-loop