Hey,

i have succeed to make it works with the following in the main.py, my problem was due to the port which was already in use, and then i have to take another one.

add the import

from threading import Thread
from urllib.parse import unquote

then just before the main function add

class WebSocketsListener(Thread):
"""Thread chargé d'ecouter les messages sur la websocket."""

def __init__(self, assistant):
    Thread.__init__(self)
    self.websocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    self.websocket.bind(('127.0.0.1', 8081))
    self.assistant = assistant


def run(self):
    print ("Open socket")

    while True:
        self.websocket.listen(5)
        client, address = self.websocket.accept()
        print (format( address ))

        response = client.recv(255)
        if response != "":
            print (response)
            str_response = response.decode("utf-8")
            if 'assistant' in str_response:
                
                if 'mode' in str_response:
                    if 'start' in str_response:
                        print("start the assistant") 
                        self.assistant.start_conversation()
                    if 'stop' in str_response: 
                        print("stop  the assistant") 
                        self.assistant.stop_conversation()

                elif 'say' in str_response:
                    token = str_response[str_response.find("say=")+4:str_response.find("HTTP")-1]
                    token = unquote(token)
                    say(token)

    print ("Close socket")
    client.close()
    stock.close()

in the main function just before the for event in events

    webSocketsListener = WebSocketsListener(assistant)
    webSocketsListener.start()

With this, open a web browser and write
http://127.0.0.1:8081/assistant?mode=start
it will start manually the assistant like with the hotword"ok google"
http://127.0.0.1:8081/assistant?mode=stop
to stop the assistant if the conversation is too long
http://127.0.0.1:8081/assistant?say=Hello karim how are you
and then gassistPI will say what you write

in the magic mirror module, you have to send this request in the node helper.js

 socketNotificationReceived: function(notification, payload) {

    var res = "";
    var ipadress = "127.0.0.1";
    var port = "8081";


console.log("google assistant Node Helper Received a socket notification: " + notification + " payload:" + payload);
if (notification === "ASSISTANT_START"){
	request("http://"+ipadress+":"+port+"/assistant?mode=start", { json: true }, (err, res, body) => {
		if (err) { return console.log(err); }
		console.log(body.url);
		console.log(body.explanation);
	});
}
else if (notification === "ASSISTANT_STOP"){
	request("http://"+ipadress+":"+port+"/assistant?mode=stop", { json: true }, (err, res, body) => {
		if (err) { return console.log(err); }
		console.log(body.url);
		console.log(body.explanation);
	});
	
}
else if (notification === "ASSISTANT_SAY"){
	console.log("assistant payload:"+payload);
	request("http://"+ipadress+":"+port+"/assistant?say="+payload, { json: true }, (err, res, body) => {
		if (err) { return console.log(err); }
		console.log(body.url);
		console.log(body.explanation);
	});
}		
}	

Thanks for your help