simple expressjs logging middleware

There is a small trick to configure an expressjs middleware function to capture a request's run time and status. Here it is:

const serverLogger = (req, res, next) => {
    const startMs = Date.now();
    res.on("finish", () => {
        log.info(
            {
                req: {
                    path: req.path,
                },
                res: {
                    statusCode: res.statusCode,
                },
                timeMs: (Date.now() - startMs),
            },
        );
    });
    next();
};

app.use(serverLogger);