node-altcoin v0.1.2

A Node.js Altcoin Client!

node-altcoin is a altcoin client for Node.js. It is a fork of the excellent Kapitalize Bitcoin Client (now removed from GitHub) intended for use with most altcoins. The purpose of this repository is:

• Provide a one-stop resource for the Node.js developer to get started with altcoin integration.
• Promote Node.js development of altcoin web apps.
• Identify and address any incompatibilities with the altcoins and Bitcoin APIs that exist now and/or in the future.

Dependencies

You'll need a running instance of a litecoind to connect with.

Then, install the node-altcoin NPM package.

npm install node-altcoin

or

npm install git://github.com/nrpatten/node-altcoin/

Examples

Some code examples follow below.

var altcoin = require('node-altcoin')()

altcoin.auth('myusername', 'mypassword')

altcoin.getDifficulty(function() {
    console.log(arguments);
})

Chaining

Pretty much everything is chainable.

var altcoin = require('node-altcoin')()

altcoin
.auth('MyUserName', 'mypassword')
.getNewAddress()
.getBalance()

Methods

The Litecoin API is supported as direct methods. Use either camelcase or lowercase.

altcoin.getNewAddress(function(err, address) {
    this.validateaddress(address, function(err, info) {

    })
})

.exec(command string, ...arguments..., callback function)

Executes the given command with optional arguments. Function callback defaults to console.log. All of the API commands are supported in lowercase or camelcase. Or uppercase. Anycase!

altcoin.exec('getNewAddress')

altcoin.exec('getbalance', function(err, balance) {

})

.set(key string, object, value optional)

Accepts either key & value strings or an Object containing settings, returns this for chainability.

altcoin.set('host', '127.0.0.1')

.get(key string)

Returns the specified option's value

altcoin.get('user')

.auth(user string, pass string)

Generates authorization header, returns this for chainability

Commands

All Litecoin API commands are supported, in lowercase or camelcase form.

Generation is limited to genproclimit processors, -1 is unlimited.

Options

You may pass options to the initialization function or to the set method.

var altcoin = require('altcoin')({
    user:'user'
})

altcoin.set('pass', 'somn')
altcoin.set({port:7142})

Available options and default values:

• host localhost
• port 7142
• user
• pass
• passphrasecallback
• https
• ca

Passphrase Callback

With an encryped wallet, any operation that accesses private keys requires a wallet unlock. A wallet is unlocked using the walletpassphrase <passphrase> <timeout> JSON-RPC method: the wallet will relock after timeout seconds.

You may pass an optional function passphrasecallback to the node-altcoin initialization function to manage wallet unlocks. passphrasecallback should be a function accepting three arguments:

function(command, args, callback) {}

• command is the command that failed due to a locked wallet.
• args is the arguments for the failed command.
• callback is a typical node-style continuation callback of the form function(err, passphrase, timeout) {}. Call callback with the wallet passphrase and desired timeout from within your passphrasecallback to unlock the wallet.

You may hard code your passphrase (not recommended) as follows:

var altcoin = require('node-altcoin')({
    passphrasecallback: function(command, args, callback) {
        callback(null, 'passphrase', 30);
    }
})

Because passphrasecallback is a continuation, you can retrieve the passphrase in an asynchronous manner. For example, by prompting the user:

var readline = require('readline')

var rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout
})

var altcoin = require('node-altcoin')({
  passphrasecallback: function(command, args, callback) {
    rl.question('Enter passphrase for "' + command + '" operation: ', function(passphrase) {
      if (passphrase) {
        callback(null, passphrase, 1)
      } else {
        callback(new Error('no passphrase entered'))
      }
    })
  }
})

Secure RPC with SSL

By default altcoind exposes its JSON-RPC interface via HTTP; that is, all RPC commands are transmitted in plain text across the network! To secure the JSON-RPC channel you can supply altcoind with a self-signed SSL certificate and an associated private key to enable HTTPS. For example, in your altcoin.conf:

rpcssl=1
rpcsslcertificatechainfile=/etc/ssl/certs/altcoind.crt
rpcsslprivatekeyfile=/etc/ssl/private/altcoind.pem

In order to securely access an SSL encrypted JSON-RPC interface you need a copy of the self-signed certificate from the server: in this case altcoind.crt. Pass your self-signed certificate in the ca option and set https: true and node-altcoin is secured!

var fs = require('fs')

var ca = fs.readFileSync('altcoind.crt')

var altcoin = require('node-altcoin')({
  user: 'rpcusername',
  pass: 'rpcpassword',
  https: true,
  ca: ca
})