ecstatic/lib/ecstatic/etag.js

A simple static file server middleware that works with both Express and Flatiron

'use strict';

module.exports = (stat, weakEtag) => {
  let etag = `"${[stat.ino, stat.size, JSON.stringify(stat.mtime)].join('-')}"`;
  if (weakEtag) {
    etag = `W/${etag}`;
  }
  return etag;
};