ethjs / ethjs-util

A simple set of Ethereum JS utilities such toBuffer and isHexPrefixed.

ethjs

A highly optimised, light-weight JS utility for Ethereum based on web3.js, but lighter, async only and using BN.js.

Only 106 kB minified!

Install

npm install --save ethjs

CDN

<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/[email protected]/dist/ethjs.min.js"></script>

Note, exports to window.Eth global.

Usage

const Eth = require('ethjs');
const eth = new Eth(new Eth.HttpProvider('https://ropsten.infura.io'));

eth.getBlockByNumber(45300, true, (err, block) => {
  // result null { ...block data... }
});

const etherValue = Eth.toWei(72, 'ether');

// result <BN: 3e733628714200000>

const tokenABI = [{
  "constant": true,
  "inputs": [],
  "name": "totalSupply",
  "outputs":[{"name": "","type": "uint256"}],
  "payable": false,
  "type": "function",
}];

const token = eth.contract(tokenABI).at('0x6e0E0e02377Bc1d90E8a7c21f12BA385C2C35f78');

token.totalSupply().then((totalSupply) => {
  // result <BN ...>  4500000
});

// token.transfer( ... ).then(txHash => eth.getTransactionSuccess(txHash)).then(receipt => console.log(receipt));

About

A simple module for building dApps and applications that use Ethereum.

Please see our complete user-guide for more information.

Contributing

Please help better the ecosystem by submitting issues and pull requests to ethjs. We need all the help we can get to build the absolute best linting standards and utilities. We follow the AirBNB linting standard and the unix philosophy.

Guides

You'll find more detailed information on using ethjs and tailoring it to your needs in our guides:

• User guide - Usage, configuration, FAQ and complementary tools.
• Developer guide - Contributing to ethjs and writing your own code and coverage.
• Examples - Examples of ethjs in use.

Help out

There is always a lot of work to do, and will have many rules to maintain. So please help out in any way that you can:

• Create, enhance, and debug ethjs rules (see our guide to "Working on rules").
• Improve documentation.
• Chime in on any open issue or pull request.
• Open new issues about your ideas for making ethjs better, and pull requests to show us how your idea works.
• Add new tests to absolutely anything.
• Create or contribute to ecosystem tools.
• Spread the word!

Please consult our Code of Conduct docs before helping out.

We communicate via issues and pull requests.

Important documents

• Changelog
• Code of Conduct
• License

Our Relationship with Ethereum & EthereumJS

We would like to mention that we are not in any way affiliated with the Ethereum Foundation. However, we love the work they do and work with them often to make Ethereum great! Our aim is to support the Ethereum ecosystem with a policy of diversity, modularity, simplicity, transparency, clarity, optimization and extensibility.

Many of our modules use code from web3.js and the ethereumjs- repositories. We thank the authors where we can in the relevant repositories.

Special Thanks

ethjs was built by a strong community of Ethereum developers. A special thanks to:

• Fabian Vogelsteller - for his work on Mist and web3.js
• Tim Coulter - for his work on TestRPC and Truffle
• Aaron Davis - for his guidence and work on MetaMask and ethereumjs
• Richard Moore - for his work on ethers-io and ethers-wallet from which so much of ethjs is build from
• Karl Floersch - for his guidence and support
• Martin B. - for his work on ethereumjs
• Alex Beregszaszi - for his work on ethereumjs
• Vitalik Buterin - for creating Ethereum

Licence

This project is licensed under the MIT license, Copyright (c) 2016 Nick Dodson. For more information see LICENSE.md.

The MIT License

Copyright (c) 2016 Nick Dodson. nickdodson.com

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.

ethjs-util's Issues

Is there any way to create a RLP encoded transaction with ethjs?

Trying to get in touch regarding a security issue

Hey there!

I'd like to report a security issue but cannot find contact instructions on your repository.

If not a hassle, might you kindly add a SECURITY.md file with an email, or another contact method? GitHub recommends this best practice to ensure security issues are responsibly disclosed, and it would serve as a simple instruction for security researchers in the future.

Thank you for your consideration, and I look forward to hearing from you!

(cc @huntr-helper)

intToHex encodes values incorrectly

ethjs-util

Before opening a new issue, please take a moment to review our community guidelines to make the contribution process easy and effective for everyone involved.

Before opening a new issue, you may find an answer in already closed issues:
https://github.com/ethjs/ethjs-util/issues?q=is%3Aissue+is%3Aclosed

Issue Type

• [X ] Bug (https://github.com/ethjs/ethjs-util/blob/master/.github/CONTRIBUTING.md#bug-reports)
• Feature (https://github.com/ethjs/ethjs-util/blob/master/.github/CONTRIBUTING.md#feature-requests)

Description

Ethereum declares that hex values should be encoded compactly.

0x0
0x1
0x11

are all valid

0x
0x00
0x01

are not

This causes problems when this library is used in products that talk to software that adheres more strictly to the standard - e.g. go-ethereum linked code talking to ganache.

This stems from

https://github.com/ethjs/ethjs-util/blob/master/src/index.js#L4-L33

(Add images if possible)

Steps to reproduce

(Add link to a demo on https://jsfiddle.net or similar if possible)

Versions

• Node/NPM:
• Browser:

addHexPrefix

What do you think about adding addHexPrefix ? Since we have stripHexPrefix and isHexPrefix here it would be nice if we could move addHexPrefix from ethereumjs-util to here also

intToBuffer() fails for numbers that produce odd length hex strings

ethjs-util

Issue Type

• Bug (https://github.com/ethjs/ethjs-util/blob/master/.github/CONTRIBUTING.md#bug-reports)
• Feature (https://github.com/ethjs/ethjs-util/blob/master/.github/CONTRIBUTING.md#feature-requests)

Description

The intToBuffer() function is broken after this PR was merged: #7

It fails for numbers that don't produce an even length hex string. It's breaking the following modules:

• ethereumjs-util: ethereumjs/ethereumjs-util#132
• ethereumjs-blockchain: ethereumjs/ethereumjs-blockchain#56

Steps to reproduce

const util = require('ethjs-util')

const buf = util.intToBuffer(1);
console.log(buf) // output: "<Buffer >" (expected: "<Buffer 01>")
assert.equal(buf.toString('hex'), '01');

Versions

• Node/NPM: 9.8.0
• Browser: N/A

doc bug - There is no addHexPrefix

Docs say there is an addHexPrefix but there isn't