Log request middleware

log.js

// log request middleware
const getActualRequestDurationInMilliseconds = start => {
    const NS_PER_SEC = 1e9; //  convert to nanoseconds
    const NS_TO_MS = 1e6; // convert to milliseconds
    const diff = process.hrtime(start);
    return (diff[0] * NS_PER_SEC + diff[1]) / NS_TO_MS;
};
app.use(function(req, res, next) {
    const current_datetime = new Date();
    const formatted_date =
        current_datetime.getFullYear() +
        '-' +
        (current_datetime.getMonth() + 1) +
        '-' +
        current_datetime.getDate() +
        ' ' +
        current_datetime.getHours() +
        ':' +
        current_datetime.getMinutes() +
        ':' +
        current_datetime.getSeconds();
    const method = req.method;
    const url = req.url;
    const status = res.statusCode;
    const start = process.hrtime();
    const durationInMilliseconds = getActualRequestDurationInMilliseconds(
        start
    );
    const log = `[${formatted_date}] ${method}:${url} ${status} ${durationInMilliseconds.toLocaleString()} ms`;
    console.log(log);
    return next();
});