1# hash-base
2
3[![NPM Package](https://img.shields.io/npm/v/hash-base.svg?style=flat-square)](https://www.npmjs.org/package/hash-base)
4[![Build Status](https://img.shields.io/travis/crypto-browserify/hash-base.svg?branch=master&style=flat-square)](https://travis-ci.org/crypto-browserify/hash-base)
5[![Dependency status](https://img.shields.io/david/crypto-browserify/hash-base.svg?style=flat-square)](https://david-dm.org/crypto-browserify/hash-base#info=dependencies)
6
7[![js-standard-style](https://cdn.rawgit.com/feross/standard/master/badge.svg)](https://github.com/feross/standard)
8
9Abstract base class to inherit from if you want to create streams implementing the same API as node crypto [Hash][1] (for [Cipher][2] / [Decipher][3] check [crypto-browserify/cipher-base][4]).
10
11## Example
12
13```js
14const HashBase = require('hash-base')
15const inherits = require('inherits')
16
17// our hash function is XOR sum of all bytes
18function MyHash () {
19  HashBase.call(this, 1) // in bytes
20
21  this._sum = 0x00
22}
23
24inherits(MyHash, HashBase)
25
26MyHash.prototype._update = function () {
27  for (let i = 0; i < this._block.length; ++i) this._sum ^= this._block[i]
28}
29
30MyHash.prototype._digest = function () {
31  return this._sum
32}
33
34const data = Buffer.from([ 0x00, 0x42, 0x01 ])
35const hash = new MyHash().update(data).digest()
36console.log(hash) // => 67
37```
38You also can check [source code](index.js) or [crypto-browserify/md5.js][5]
39
40## LICENSE
41
42MIT
43
44[1]: https://nodejs.org/api/crypto.html#crypto_class_hash
45[2]: https://nodejs.org/api/crypto.html#crypto_class_cipher
46[3]: https://nodejs.org/api/crypto.html#crypto_class_decipher
47[4]: https://github.com/crypto-browserify/cipher-base
48[5]: https://github.com/crypto-browserify/md5.js
49