How to save my cam stream in my server realtime node js?

how can I save my chunks of streams which converted into blobs in my node js server real-time

client.js | I am my cam stream as binary to my node js server

    handleBlobs = async (blob) => {

        let arrayBuffer = await new Response(blob).arrayBuffer()

        let binary = new Uint8Array(arrayBuffer)

        this.postBlob(binary)


    };

 postBlob = blob => {

        axios.post('/api',{blob})
            .then(res => {
                console.log(res)
            })
    };

server.js

app.post('/api', (req, res) => {
    console.log(req.body)
});

how can I store the incoming blobs or binary into one video file at the end of video recording completion.

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