bitcoinjs-lib/README.md

# bitcoinjs-lib

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A pure JavaScript Bitcoin library for node.js and browsers.
A continued implementation of the original `0.1.3` version used by over a million wallet users; and the backbone for almost all Bitcoin web wallets in production today.


## Should I use this in production?
If you are thinking of using the master branch of this library in production, stop.
Master is not stable; it is our development branch, and only tagged releases may be classified as stable.

Master is currently being heavily refactored to clean things up, add new functionality and merge improvements from the community.
If you are looking for the original, it is tagged as `0.1.3`.
We are releasing quasi-stable releases tagged under `0.2.x`, with the expectation that this is still beta software and is `PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED`.

This is not the original bitcoinjs-lib that was not updated for a long time.


## Features

- Bitcoin Testnet and Mainnet (production) support
- [HD Wallets](https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki)
- Random private key generation that uses [window.crypto.getRandomValues](https://developer.mozilla.org/en-US/docs/Web/API/Window.crypto) in the underlying implementation.
- ECDSA signing and verification
- Standard Transaction creation (pay-to-pubkey-hash), support for multisignature transactions
- A (somewhat incomplete) wallet implementation, improvements ongoing


## Installation

`npm install bitcoinjs-lib`

Note: The npm version is currently out of date, are working to resolve this. The best way to use the latest code is to clone the repository.


## Setup

### Node.js

    var bitcoin = require('bitcoinjs-lib')

From the repo:

    var bitcoin = require('./src/index.js')


### Browser

Compile `bitcoinjs-min.js` with the following command:

    $ npm run-script compile

After loading this file in your browser, you will be able to use the global `Bitcoin` object.


## Usage

These examples assume you are running bitcoinjs-lib in the browser.


### Generating a Bitcoin address

```javascript

key = Bitcoin.ECKey.makeRandom()

// Print your private key (a hex string)
console.log(key.toString())
// => 8c112cf628362ecf4d482f68af2dbb50c8a2cb90d226215de925417aa9336a48

// Print your public key (defaults to a Bitcoin address)
console.log(key.pub.getAddress())
// => 14bZ7YWde4KdRb5YN7GYkToz3EHVCvRxkF
```

### Creating a Transaction

```javascript
tx = new Bitcoin.Transaction()

// Add the input (who is paying) of the form [previous transaction hash, index of the output to use]
tx.addInput("aa94ab02c182214f090e99a0d57021caffd0f195a81c24602b1028b130b63e31", 0)

// Add the output (who to pay to) of the form [payee's address, amount in satoshis]
tx.addOutput("1Gokm82v6DmtwKEB8AiVhm82hyFSsEvBDK", 15000)

// Initialize a private key using hex
key = Bitcoin.ECKey.fromHex("8c112cf628362ecf4d482f68af2dbb50c8a2cb90d226215de925417aa9336a48")

// Sign the first input with the new key
tx.sign(0, key)

// Print transaction serialized as hex
console.log(tx.serializeHex())
// => 0100000001313eb630b128102b60241ca895f1d0ffca2170d5a0990e094f2182c102ab94aa000000008a47304402200169f1f844936dc60df54e812345f5dd3e6681fea52e33c25154ad9cc23a330402204381ed8e73d74a95b15f312f33d5a0072c7a12dd6c3294df6e8efbe4aff27426014104e75628573696aed32d7656fb35e9c71ea08eb6492837e13d2662b9a36821d0fff992692fd14d74fdec20fae29128ba12653249cbeef521fc5eba84dde0689f27ffffffff01983a0000000000001976a914ad618cf4333b3b248f9744e8e81db2964d0ae39788ac00000000

// You could now push the transaction onto the Bitcoin network manually (see https://blockchain.info/pushtx)
```


## Projects utilizing bitcoinjs-lib

- [Blockchain.info Wallet](http://blockchain.info/wallet)
- [Bitaddress.org](https://www.bitaddress.org)
- [Coinpunk](https://coinpunk.com)
- [DarkWallet](https://darkwallet.unsystem.net)
- [GreenAddress](https://greenaddress.it)

Feel free to send pull requests to have your project/startup listed here.


## Contributing

### Instructions

1. Fork the repo
2. Push changes to your fork
3. Create a pull request


### Running the test suite

    $ npm test


## Alternatives

- [Bitcore](https://github.com/bitpay/bitcore)
- [Cryptocoin](https://github.com/cryptocoinjs/cryptocoin)


## License

This library is free and open-source software released under the MIT license.


## Copyright

BitcoinJS (c) 2011-2012 Stefan Thomas
Released under MIT license
http://bitcoinjs.org/

CryptoJS (c) 2009–2012 by Jeff Mott
Released under New BSD license
http://code.google.com/p/crypto-js/