Event Emitter memory leak! messages added twice!

[artstylee]

hi guys!
im facing an issue which i cannot solve for 2 days xD
here is the code
front(react)

socket.emit("msg", activechat, token, userlogin, message)

useEffect(() => {
        socket.on(activechat, (bdmsg) => {
            console.log(bdmsg) // issue is here
        })
        return () => {
            socket.offAny()
        }
    }, [activechat])


useEffect(() => {
    socket.on(userlogin, (msg) => {
        if (msg === "refresh") {
            socket.emit(userlogin, "refresh ok")
        }
    })
    return () => {
        socket.offAny()
    }
}, [])

and nodejs

io.on("connect", (socket) => {
    socket.on("msg", (activechat, token, userlogin, message) => {
        socket.emit(userlogin, "refresh")
        socket.on(userlogin, (msg) => {
            if (msg === "refresh ok") {
                socket.emit(activechat, message)
            }
        })
    })
})

the issue is when i type something ive got messages from the past in the console

and the error on the server

(node:16376) MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 test listeners added to [Socket]. Use emitter.setMaxListeners() to increase limit
(Use `node --trace-warnings ...` to show where the warning was created)

when i click -send- too many times it cause too much re-renders so the browser freezes
do you have any ideas why its happening?
i made a return from both useeffects but its still cause an error

[darrachequesne]

I think that's because a new listener gets added each time you receive a "msg" event on the server side. How about:

io.on("connect", (socket) => {
    socket.on("msg", (activechat, token, userlogin, message) => {
        socket.emit(userlogin, "refresh")
    })
    
    socket.on(userlogin, (msg) => {
        if (msg === "refresh ok") {
            socket.emit(activechat, message)
        }
    })
})

[artstylee]

i cannot use activechat and userlogin and message outside the "msg" listener
socket.on(userlogin, (msg) => {....
thats how i register a new listener for every new person in the chat

[artstylee]

    socket.on("msg", (activechat, token, userlogin, message) => {  // get message & token & userlogin etc
       // check token -> invalid
        socket.emit(userlogin, "refresh") // go refresh man
        socket.on("refresh", (msg) => { // start listening while front is refreshing and if OK emit a message from "msg" listener
            if (msg === "refresh ok") {
                socket.emit(activechat, message)
            }
        })
    })

[artstylee]

io.on("connect", (socket) => {
    socket.on("msg", (activechat, token, userlogin, message) => {
        socket.emit(userlogin, "refresh") 
        //basically i want to hold the "message" arg until the user makes a refresh and when its done validate the token again and add to database. thats why i need this args
    })
    
    socket.on(userlogin, (msg) => {
        if (msg === "refresh ok") {
            socket.emit(activechat, message)
        }
    })
})

[artstylee]

looks like i solved the issue with socket.once ! thanks!