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.

Command	Parameters	Description	Requires unlocked wallet?
addmultisigaddress	[nrequired] ["key","key"] [account]	Currently only available on testnet Add a nrequired-to-sign multisignature address to the wallet. Each key is a altcoin address or hex-encoded public key. If [account] is specified, assign address to [account].	N
backupwallet	[destination]	Safely copies wallet.dat to destination, which can be a directory or a path with filename.	N
dumpprivkey	[altcoinaddress]	Reveals the private key corresponding to	Y
encryptwallet	[passphrase]	Encrypts the wallet with	N
getaccount	[altcoinaddress]	Returns the account associated with the given address.	N
getaccountaddress	[account]	Returns the current altcoin address for receiving payments to this account.	N
getaddressesbyaccount	[account]	Returns the list of addresses for the given account.	N
getbalance	[account] [minconf=1]	If [account] is not specified, returns the server's total available balance. If [account] is specified, returns the balance in the account.	N
getblock	[hash]	Returns information about the given block hash.	N
getblockcount		Returns the number of blocks in the longest block chain.	N
getblockhash	[index]	Returns hash of block in best-block-chain at	N
getblocknumber		Deprecated. Use getblockcount.	N
getconnectioncount		Returns the number of connections to other nodes.	N
getdifficulty		Returns the proof-of-work difficulty as a multiple of the minimum difficulty.	N
getgenerate		Returns true or false whether altcoind is currently generating hashes	N
gethashespersec		Returns a recent hashes per second performance measurement while generating.	N
getinfo		Returns an object containing various state info.	N
getmemorypool	[data]	If [data] is not specified, returns data needed to construct a block to work on: "version": block version "previousblockhash": hash of current highest block "transactions": contents of non-coinbase transactions that should be included in the next block "coinbasevalue": maximum allowable input to coinbase transaction, including the generation award and transaction fees "time": timestamp appropriate for next block "bits": compressed target of next block If [data] is specified, tries to solve the block and returns true if it was successful.	N
getmininginfo		Returns an object containing mining-related information: blocks currentblocksize currentblocktx difficulty errors generate genproclimit hashespersec pooledtx testnet	N
getnewaddress	[account]	Returns a new altcoin address for receiving payments. If [account] is specified (recommended), it is added to the address book so payments received with the address will be credited to [account].	N
getreceivedbyaccount	[account] [minconf=1]	Returns the total amount received by addresses with [account] in transactions with at least [minconf] confirmations. If [account] not provided return will include all transactions to all accounts. (version 0.3.24-beta)	N
getreceivedbyaddress	[altcoinaddress] [minconf=1]	Returns the total amount received by	N
gettransaction	[txid]	Returns an object about the given transaction containing: "amount": total amount of the transaction "confirmations": number of confirmations of the transaction "txid": the transaction ID "time": time the transaction occurred "details" - An array of objects containing: "account" "address" "category" "amount"	N
getwork	[data]	If [data] is not specified, returns formatted hash data to work on: "midstate": precomputed hash state after hashing the first half of the data "data": block data "hash1": formatted hash buffer for second hash "target": little endian hash target If [data] is specified, tries to solve the block and returns true if it was successful.	N
help	[command]	List commands, or get help for a command.	N
importprivkey	[altcoinprivkey] [label]	Adds a private key (as returned by dumpprivkey) to your wallet.	Y
keypoolrefill		Fills the keypool, requires wallet passphrase to be set.	Y
listaccounts	[minconf=1]	Returns Object that has account names as keys, account balances as values.	N
listreceivedbyaccount	[minconf=1] [includeempty=false]	Returns an array of objects containing: "account": the account of the receiving addresses "amount": total amount received by addresses with this account "confirmations": number of confirmations of the most recent transaction included	N
listreceivedbyaddress	[minconf=1] [includeempty=false]	Returns an array of objects containing: "address": receiving address "account": the account of the receiving address "amount": total amount received by the address "confirmations": number of confirmations of the most recent transaction included To get a list of accounts on the system, execute altcoind listreceivedbyaddress 0 true	N
listsinceblock	[blockhash] [target-confirmations]	Get all transactions in blocks since block [blockhash], or all transactions if omitted.	N
listtransactions	[account] [count=10] [from=0]	Returns up to [count] most recent transactions skipping the first [from] transactions for account [account]. If [account] not provided will return recent transaction from all accounts.	N
move	[fromaccount] [toaccount] [amount] [minconf=1] [comment]	Move from one account in your wallet to another	N
sendfrom	[fromaccount] [toaltcoinaddress] [amount] [minconf=1] [comment] [comment-to]		Y
sendmany	[fromaccount] [address:amount,...] [minconf=1] [comment]	amounts are double-precision floating point numbers	Y
sendtoaddress	[altcoinaddress] [amount] [comment] [comment-to]		Y
setaccount	[altcoinaddress] [account]	Sets the account associated with the given address. Assigning address that is already assigned to the same account will create a new address associated with that account.	N
setgenerate	[generate] [genproclimit]	[generate] is true or false to turn generation on or off. Generation is limited to [genproclimit] processors, -1 is unlimited.	N
signmessage	[altcoinaddress] [message]	Sign a message with the private key of an address.	Y
settxfee	[amount]	[amount] is a real and is rounded to the nearest 0.00000001	N
stop		Stop altcoin server.	N
validateaddress	[altcoinaddress]	Return information about [altcoinaddress].	N
verifymessage	[altcoinaddress] [signature] [message]	Verify a signed message.	N
walletlock		Removes the wallet encryption key from memory, locking the wallet. After calling this method, you will need to call walletpassphrase again before being able to call any methods which require the wallet to be unlocked.	N
walletpassphrase	[passphrase] [timeout]	Stores the wallet decryption key in memory for	N
walletpassphrasechange	[oldpassphrase] [newpassphrase]	Changes the wallet passphrase from	N

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
})