Create an md5 hash string of a javascript object using crypto createHash, update, and digest hex

hash-object.js

var crypto = require('crypto');

exports.hashObject = function (object) {
  var hash = crypto.createHash('md5')
    .update(JSON.stringify(object, function (k, v) {
      if (k[0] === "_") return undefined; // remove api stuff
      else if (typeof v === "function") // consider functions
        return v.toString();
      else return v;
    }))
    .digest('hex');
  return hash;
}

JSON.stringify() is not guaranteed to return keys in the same order.

@dhwaneetbhatt – interesting... thanks for the note!
I have an idea of how this could be fixed by keeping the hash state in its own variable, then using the more common for x in obj like loop.
At this point, (given I put this together 6.5 years ago), I'd probably question the goals of hashing an object anyways, is it for keeping a version?
If it's simply for serialization, then it's probably okay to JSON.stringify for the database entry (if you can't use jsonb), but if it's to sort of use as some kind of key, perhaps a simple Map / WeakMap might be more appropriate (and far more efficient).