ion-hash-js

ion-hash-js

A JavaScript implementation of the Ion Hash Specification.

License

This library is licensed under the Apache 2.0 License.

An implementation of Amazon Ion Hash for JavaScript.

Getting Started

This library is designed to work with Node 8/ES5/CommonJS.

Node

1. Add ion-hash-js to your dependencies using npm:

   npm install --save ion-hash-js
   

2. Use the library to read an Ion value and generate an Ion hash:

   import * as ion from 'ion-js';
   import {cryptoIonHasherProvider, makeHashReader} from 'ion-hash-js';
   
   let ionStr = '[1, 2, 3]';
   let hashReader = makeHashReader(
           ion.makeReader(ionStr),
           cryptoIonHasherProvider('md5'));
   hashReader.next();
   hashReader.next();
   let digest = hashReader.digest();
   
   process.stdout.write('digest:  ');
   digest.forEach((b: number) => {
       process.stdout.write(('0' + (b & 0xFF).toString(16)).slice(-2) + ' ');
   });
   process.stdout.write('\n');
   

   produces:

   digest: 8f 3b f4 b1 93 5c f4 69 c9 c1 0c 31 52 4b 26 25

3. Use the library to write Ion data:

   import * as ion from 'ion-js';
   import {IonTypes} from 'ion-js';
   import {cryptoIonHasherProvider, makeHashWriter} from 'ion-hash-js';
   
   let hashWriter = makeHashWriter(
           ion.makeTextWriter(),
           cryptoIonHasherProvider('md5'));
   hashWriter.stepIn(IonTypes.LIST);
   hashWriter.writeInt(1);
   hashWriter.writeInt(2);
   hashWriter.writeInt(3);
   hashWriter.stepOut();
   let digest = hashWriter.digest();
   
   process.stdout.write('digest:  ');
   digest.forEach((b: number) => {
       process.stdout.write(('0' + (b & 0xFF).toString(16)).slice(-2) + ' ');
   });
   process.stdout.write('\n');
   

   produces:

   digest: 8f 3b f4 b1 93 5c f4 69 c9 c1 0c 31 52 4b 26 25

Development

This repository contains a git submodule called ion-hash-test, which holds test data used by ion-hash-js's unit tests.

The easiest way to clone the ion-hash-js repository and initialize its ion-hash-test submodule is to run the following command:

$ git clone --recursive https://github.com/amzn/ion-hash-js.git ion-hash-js

Alternatively, the submodule may be initialized independently from the clone by running the following commands:

$ git submodule init
$ git submodule update

Known Issues

Any tests commented out in tests/ion_hash_tests.ion are not expected to work at this time.