Simple Express Logging Middleware

snippet.js

//don't log tests
if (process.env.NODE_ENV !== 'test') { 
  app.use(  (req, res, next) => {
    //don't log OPTIONS calls
    if (req.method !== 'OPTIONS' ) {

      let startTime = Date.now();

      res.on('finish', ()=> {

        //sanitize and format query object
        const  query = Object.entries(req.query).map( v =>
          `${v[0]}=${v[0]==='access-token'?'given':v[1]}`
        ).join("&")

        const msg = `Http Request  ${req.method} ${req.path} - ${res.statusCode} - ${Date.now() - startTime}ms - ${query}`

        if(res.statusCode>=500){
          logger.error(msg)
        } else if(res.statusCode>=400){
          logger.warn(msg)
        } else {
          logger[process.env.LOG_LEVEL || 'info'](message)
        }
      });

    }
    next();
  })
}