all-terrain-hash

All Terrain Object Hashing.

Hash any javascript object, functions, undefined, warts and all. This utility takes any javascript object and hashes it in a reproducible deterministic way. Functions are decomposed into an AST, with comments and whitespace discarded. Objects are ordered in a consistent and safe way. It even takes into account the difference between an undefined and a null.

Why?

Sometimes you need to know when anything is different. For instance, if you are handling code across distributed services, or doing stuff that git should be responsible for ;)

Usage

const ath = require('all-terrain-hash')
 
let exampleObject = {
  "I've got a nice long key name": function withAFunction (a, b, c=3) {
    return "Why, how nice this all is today. I hope we do not get crushed into a hash string."
  },
  "Sure we won't": (world)=>this,
  "question": {"Have you seen my mirror?": {"response": "Why yes, I have, let me get it for you."}}
}
exampleObject.question.response.mirror = exampleObject
 
ath.hex(exampleObject)
// 'ab1934e351c6a2e99ab84e18eef04bfc2963896e4a75a76a99af84e7a00be6738d9f2f35b9aa322f5f4a1d7f82a037ee082658af08708e2175a4b63539f280f0'
 
ath(exampleObject)
// Uint8Array 
// Blake2b { digestLength: 64, finalized: false, pointer: 64 }

API

ath(obj, [key], [salt], [personal])

This takes an ordinary object and will deterministically hash it via blake2b. It returns a Uint8Array by default. All optionals arguments such as key, salt, and personal will be passed to blake2b.

.hex(obj, [key], [salt], [personal])

This takes an ordinary object and will deterministically hash it via blake2b. Unlike the function above, it returns it as a hex string. All optionals arguments such as key, salt, and personal will be passed to blake2b.

Installation

$ npm install all-terrain-hash

License

MIT