index.html

<!DOCTYPE html>
<html>
        <head>
                <title>Test</title>
                <meta charset="UTF-8">
        </head>
        <body>
            <h1>Test</h1>
            <script>
                console.log('fetch stream');
                fetch('/stream').then(async response => {
                    console.log('response');
                    const reader = response.body.getReader();
                    while(true) {
                        const {done, value} = await reader.read();

                        if (done) {
                            console.log("Done!");
                            break;
                        }

                        // value is Uint8Array of the chunk bytes
                        var str = String.fromCharCode.apply(null, value);
                        console.log(str.length);
                    }
                });
            </script>
        </body>
</html>