metrohash

node-metrohash

Wrapper around MetroHash.

Installation

$ npm install metrohash

API change!

Between v1 and v2, the API for this library has changed to allow for maximum hashing speed.

The biggest change is that a calculated hash is now returned as a (hex-encoded) string instead of a Buffer.

If a Buffer is still required, it's easy to convert the string:

let buffer = Buffer.from(metrohash64('input'), 'hex');

Also, the .hash() methods for the hasher classes have been removed in favor of standalone functions (see below).

Usage

The module exports 2 classes, MetroHash64 and MetroHash128, and two functions, metrohash64 and metrohash128.

The classes are meant for incremental hashing, the functions for standalone hash calculations.

Class interface

const MetroHash64 = require('metrohash').MetroHash64;

// Constructor.
MetroHash64([ seed:Number = 0 ]) : Object

// Update.
MetroHash64#update(input : [String | Buffer]) : Object

// Finalize and get hash digest.
MetroHash64#digest() : String

(likewise for MetroHash128).

Function interface

const metrohash64 = require('metrohash').metrohash64;

metrohash64(input : [String | Buffer], [ seed:Number = 0 ]) : String

(likewise for metrohash128).

Examples

//// Classes

const MetroHash64 = require('metrohash').MetroHash64;

// Instantiate using seed 123 (`new` is optional).
let hash = new MetroHash64(123);

// Update using a string as input.
hash.update('Hello, World!');

// The same as above:
// hash.update('Hello, ').update('World!');

// Finalize to get the digest as a hex string.
let digest = hash.digest();

//// Functions
const metrohash64 = require('metrohash').metrohash64;

let digest = metrohash64('Hello, World!', 123);

Speed

From v2.0 onwards, MetroHash is pretty fast.