MQTT Subscribe and Post

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Re: MQTT Subscribe and Post

Post by pythoncoder » Thu Dec 28, 2017 9:41 am

c.wait_msg() is a blocking function: this means it won't return until a message is received. This prevents you from publishing while waiting for a message. The way to proceed is to use c.check_msg(). This returns immediately. If a message has been received the callback will run as before. So your main loop might look like

Code: Select all

    while 1:
        if door_has_opened():  # Detect change of state
            c.publish(b"door", b"open")
        if door_has_closed():
            c.publish(b"door", b"closed")
        time.sleep(0.2)  # Avoid 100% CPU usage
Peter Hinch

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