withcoin-sdk v1.5.2

withcoin-sdk

withcoin Developer Kit for Node.js and the browser

This SDK is just a "draft" for now, lot of things will change as development and feedback goes, but it is enough to start developing great applications.

Nano Wallet will integrate this library instead of everything being merged in the same project. So we have a real separation between core and client.

Features:

• Easy integration
• Organised in namespaces
• Create wallets compatible with Nano Wallet client
• Simple transactions
• Mosaic transactions
• Encrypted, unencrypted and hex messaging
• Create and audit Apostilles
• Create and verify signatures
• Helpers and formatting functions
• 22 NIS API requests with promises
• Websockets for real time blockchain data
• Commented code and examples
• Browser examples ready to use out of the box

Documentation

Table of Contents

1. Introduction

• 1. Installation
• 2. Build
• 3. Organisation

2. Objects

• 1. Get objects
• 2. Create objects
• 3. More

3. Transactions

• 1. Create and prepare transaction objects
• 2. Sending prepared transactions
• 3. Transfer transactions without mosaics
• 4. Transfer transactions with mosaics

4. Communications

• 1. Create endpoints
• 2. API requests
• 3. Usage
• 4. More
• 5. Websockets
• 6. Usage
• 7. More

5. Helpers and Format

• 1. Helpers
• 2. Format

6. Private Keys

• 1. Create private keys
• 2. Create key pairs
• 3. Sign with key pair
• 4. Extract public key from key pair
• 5. Verify a signature

7. Addresses

• 1. Convert public key to an address
• 2. Verify address validity
• 3. Verify if address is from given network
• 4. More

8. Crypto Helpers
9. Wallets

• 1. Create simple wallets
• 2. Create brain wallets
• 3. Create private key wallets
• 4. Create wallet files
• 5. Decrypt account in wallet

1 - Introduction

1.1 - Installation

For the browser:

Download the library source, open the dist/ folder and put withcoin-sdk.js into your project.

Library include the require() function so you can require() the module directly

<script src="withcoin-sdk.js"></script>
<script>
  // Include the library
  var withcoin = require("withcoin-sdk").default;
  console.log(withcoin)
</script>

For Node:

Using npm:

npm install withcoin-sdk

// Use require
var withcoin = require("withcoin-sdk").default;

// ES6
import withcoin from 'withcoin-sdk';

Using build/ folder:

// Use the build/ folder
var withcoin = require("path/to/build/index.js").default;

1.2 - Build

Install dependencies:

npm install

Build:

npm run build

Build for the browser (after above build):

npm run browserify

1.3 - Organisation

The SDK is organised in namespaces and sub-namespaces.

There is 4 main namespaces:

withcoin.com

• requests: Requests to NIS and the outside world
• websockets: Connection, subscription and requests to NIS websockets

withcoin.crypto

• keyPair: Functions to create keypair from hex and sign data with it
• helpers: Miscellaneous cryptographic functions, like encrypt private key, decrypt a wallet, derive a password...
• nacl: External cryptographic library modified for withcoin
• js: Access to the crypto-js library

withcoin.model

• address: Functions regarding withcoin addresses like base32 encoding / decoding, verify, convert public key to address...
• objects: Contains usesul objects models
• fees: Contains all the transaction fees and calculation functions
• network: Contains networks types and functions related
• nodes: Contains array of nodes for different networks, default nodes, search by hash nodes...
• sinks: Contains the sink addresses for namespaces and mosaics by network
• transactions: Contains functions to prepare and send transaction objects
• transactionTypes: Contains all the withcoin transactions types
• wallet: Contains functions to create wallets

withcoin.utils

• convert: Contains convertion functions
• helpers: Contains miscellaneous helper functions
• format: Contains miscellaneous formatting functions
• nty: Contains functions to build nty data
• Serialization: Contains functions to serialize transactions

Consult the code directly for details, almost all functions are commented, with parameters, return values and types.

2 - Objects

Namespace: withcoin.model.objects

This namespace allow to easily get or create objects to use in the SDK. Each object is accessible via a keyword.

Public methods:

• get
• create

Keywords:

• common: An object to hold password and private key
• endpoint: An object containing info about a remote node
• mosaicAttachment: An object containing mosaic data to join in a transfer transaction
• mosaicDefinitionMetaDataPair: An object of objects containing mosaics properties
• invoice: An invoice object working on withcoin mobile clients
• transferTransaction: An un-prepared transfer transaction object
• signatureTransaction: An un-prepared signature transaction object

2.1 - Get objects

Return an empty object

Usage:

// Get an empty object
var object = withcoin.model.objects.get("keyword");

Example:

// Get an empty object
var transferTransaction = withcoin.model.objects.get("transferTransaction");

Return:

{
    "amount": "",
    "recipient": "",
    "recipientPublicKey": "",
    "isMultisig": false,
    "multisigAccount" : "",
    "message": "",
    "isEncrypted" : false,
    "mosaics": []
}

2.2 - Create objects

Return an object with parameters.

Using the create method takes different parameters depending of the object.

Parameters

common

endpoint

mosaicAttachment

transferTransaction

Usage:

// Create an object with parameters
var object = withcoin.model.objects.create("keyword")(param1, param2, ...);

Example:

// Create an object with parameters
var transferTransaction = withcoin.model.objects.create("transferTransaction")("TBCI2A67UQZAKCR6NS4JWAEICEIGEIM72G3MVW5S", 10, "Hello");

Return:

{
    "amount": 10,
    "recipient": "TBCI2A67UQZAKCR6NS4JWAEICEIGEIM72G3MVW5S",
    "recipientPublicKey": "",
    "isMultisig": false,
    "multisigAccount" : "",
    "message": "Hello",
    "isEncrypted" : false,
    "mosaics": []
}

2.3 - More

Consult src/model/objects.js for details about objects and creation parameters

3 - Transactions

Namespace: withcoin.model.transactions

Public methods:

• prepare
• send
• prepareMessage

Keywords:

• transferTransaction
• mosaicTransferTransaction
• signatureTransaction

This namespace is used to prepare and send transactions.

For now only preparation of simple and mosaics transactions with encrypted, unencrypted and hex messages are implemented.

3.1 - Create and prepare transaction objects

In part 2 you can see in the examples how to build a transfer transaction object, with or without data.

Transaction objects you will create via withcoin.model.objects are un-prepared transaction objects. They only contain raw / incomplete data and need to be arranged before being signed and sent.

Using the prepare method takes different parameters depending of the transaction object.

Parameters

transferTransaction

mosaicTransferTransaction

Usage:

// Prepare a transaction object
var preparedTransaction = withcoin.model.transactions.prepare("keyword")(param1, param2, ...);

Transfer transaction example:

// Create an object with parameters
var transferTransaction = withcoin.model.objects.create("transferTransaction")("TBCI2A67UQZAKCR6NS4JWAEICEIGEIM72G3MVW5S", 10, "Hello");

// Prepare the above object
var transactionEntity = withcoin.model.transactions.prepare("transferTransaction")(common, transferTransaction, withcoin.model.network.data.testnet.id)

Return:

{
	type: 257,
  	version: -1744830463,
  	signer: '0257b05f601ff829fdff84956fb5e3c65470a62375a1cc285779edd5ca3b42f6',
  	timeStamp: 62995509,
  	deadline: 62999109,
  	recipient: 'TBCI2A67UQZAKCR6NS4JWAEICEIGEIM72G3MVW5S',
  	amount: 10000000,
  	fee: 2000000,
  	message: { type: 1, payload: '48656c6c6f' },
  	mosaics: null
}

You can easily see the difference between an un-prepared transaction object (2.2) and above prepared object.

Note:

Amounts are in the smallest unit possible in a prepared transaction object:

1000000 = 1 XEM

Signature transaction example:

// Create an object with parameters (multisig account address and inner transaction hash)
var signatureTransaction = withcoin.model.objects.create("signatureTransaction")("TBCI2A67UQZAKCR6NS4JWAEICEIGEIM72G3MVW5S", "161d7f74ab9d332acd46f96650e74371d65b6e1a0f47b076bdd7ccea37903175");

// Prepare the above object
var transactionEntity = withcoin.model.transactions.prepare("signatureTransaction")(common, signatureTransaction, withcoin.model.network.data.testnet.id)

Return:

{
  type: 4098,
  version: -1744830463,
  signer: '0257b05f601ff829fdff84956fb5e3c65470a62375a1cc285779edd5ca3b42f6',
  timeStamp: 62995509,
  deadline: 62999109,
  otherHash: {
    data: '161d7f74ab9d332acd46f96650e74371d65b6e1a0f47b076bdd7ccea37903175'
  },
  otherAccount: 'TBCI2A67UQZAKCR6NS4JWAEICEIGEIM72G3MVW5S',
  fee: 6000000
}

3.2 - Sending prepared transactions

Once your transaction is prepared simply use the send method of the namespace.

Parameters

Example

// Serialize transfer transaction and announce
withcoin.model.transactions.send(common, transactionEntity, endpoint).then(function(res) {....});

return

A nemAnnounceResult object (consult api docs for more infos)

3.3 - Transfer transactions without mosaics

The two provided example speaks for themselves:

• See examples/node/transfer.js for node
• See examples/browser/transfer for browser

The node version contains only the strict necessary while browser example needs to handle form and update fees.

3.4 - Transfer transactions with mosaics

• This section is no longer used.

4 - Communications

4.1 - Create endpoints

To communicate with an NIS you need an endpoint object. The object contains the node host and port so it is easier to handle.

Examples

// Custom endpoint
var endpoint = withcoin.model.objects.create("endpoint")("http://myNode", 6789);

// Using sdk data
var endpoint = withcoin.model.objects.create("endpoint")(withcoin.model.nodes.defaultTestnet, withcoin.model.nodes.defaultPort);

4.2 - API requests

Namespace: withcoin.com.requests

22 NIS API calls and a few other external requests are implemented and organised in namespaces:

withcoin.com.requests.account

• data: Gets account data
• transactions.incoming: Gets incoming transactions
• transactions.unconfirmed: Gets unconfirmed transactions
• transactions.all: Gets all transactions
• transactions.outgoing: Gets outgoing transactions
• unlockInfo: Gets information about the maximum number of allowed harvesters and how many harvesters are already using the node

withcoin.com.requests.chain

• height: Gets the chain height
• lastBlock: Gets the last block
• time: Get network time

withcoin.com.requests.endpoint

• heartbeat: Gets the node status

withcoin.com.requests.market

• btc: Gets BTC price in $

withcoin.com.requests.supernodes

• all: Gets all supernodes info

withcoin.com.requests.transaction

• byHash: Gets a transaction by hash
• announce: Announce a transaction to the network

4.3 - Usage

Requests are wrapped in Promises which allow to use then() for callbacks

Examples:

// Gets chain height
withcoin.com.requests.chain.height(endpoint).then(function(res) {
	console.log(res)
}, function(err) {
	console.error(err)
})

// Gets account data
withcoin.com.requests.account.data(endpoint, "TBCI2A67UQZAKCR6NS4JWAEICEIGEIM72G3MVW5S").then(...);

4.4 - More

Consult src/com/requests for details about requests parameters.

• See examples/browser/monitor for browser demonstration
• See examples/node/requests for all requests in node

4.5 - WebSockets

Namespace: withcoin.com.websockets

Note: For now webSockets use two versions of SockJS to work in Node (v1.1.4) and the browser (v0.3.4). Using only latest SockJS v1.1.4, gives an error when used in browser:

XMLHttpRequest cannot load http://bob.withcoin.ninja:7778/w/messages/info?t=1429552020306. A wildcard '*' cannot be used in the 'Access-Control-Allow-Origin' header when the credentials flag is true. Origin 'null' is therefore not allowed access.

If anyone has a solution to that, it is welcome.

withcoin.com.websockets.connector

• create: Create a connector object
• close: Close the websocket connection

withcoin.com.websockets.subscribe

• errors: Subscribes to error channel

withcoin.com.websockets.subscribe.account

• data: Subscribes to account data channel
• transactions.recent: Subscribes to recent transactions channel
• transactions.confirmed: Subscribes to confirmed transactions channel
• transactions.unconfirmed: Subscribes to unconfirmed transactions channel

withcoin.com.websockets.subscribe.chain

• height: Subscribes to new chain height channel
• blocks: Subscribes to new blocks channel

withcoin.com.websockets.requests.account

• data: Requests account data from channel
• transactions.recent: Requests recent transactions from channel

4.6 - Usage

You first need to create a connector object pointing to the right endpoint then use this connector to open the connection.

If connection is a success, the connector.connect function will resolve a promise in a .then() function, in which you can request and subscribe to channels.

Subscription takes a connector and resolve in a simple callback function (.then() not supported), where your data will be received from the channel. It acts exactly like a .on('something').

Parameters

create

All subscription methods

All request methods

Example:

// Create an endpoint object
var endpoint = withcoin.model.objects.create("endpoint")(withcoin.model.nodes.defaultTestnet, withcoin.model.nodes.websocketPort);

// Address to subscribe
var address = "TBCI2A67UQZAKCR6NS4JWAEICEIGEIM72G3MVW5S";

// Create a connector object
var connector = withcoin.com.websockets.connector.create(endpoint, address);

// Connect using connector
connector.connect().then(function() {
  // If we are here we are connected
  console.log("Connected");

  // Subscribe to new blocks channel
  withcoin.com.websockets.subscribe.chain.blocks(connector, function(res) {
    console.log(res);
  });

  // Subscribe to account data channel
  withcoin.com.websockets.subscribe.account.data(connector, function(res) {
    console.log(res);
  });

  // Request account data
  withcoin.com.websockets.requests.account.data(connector);

}, function (err) {
  // If we are here connection failed 10 times (1/s).
  console.log(err);
});

4.7 - More

Consult src/com/websockets for details.

• See examples/browser/websockets for browser demonstration
• See examples/nodejs/websockets.js for Node demonstration

5 - Helpers and Format

5.1 - Helpers

Namespace: withcoin.utils.helpers

Public methods:

• needsSignature
• haveTx
• getTransactionIndex
• haveCosig
• createwithcoinTimeStamp
• fixPrivateKey
• isPrivateKeyValid
• isPublicKeyValid
• checkAndFormatUrl
• createTimeStamp
• getTimestampShort
• convertDateToString
• extendObj
• isHexadecimal
• searchMosaicDefinitionArray
• grep
• isTextAmountValid
• cleanTextAmount
• formatEndpoint

5.2 - Format

Namespace: withcoin.utils.format

Public methods:

• address
• hexMessage
• hexToUtf8
• importanceTransferMode
• levyFee
• nemDate
• nemImportanceScore
• nemValue
• pubToAddress
• splitHex
• supply
• supplyRaw
• mosaicIdToName
• txTypeToName

Format address

Add hyphens to unformatted address.

Parameters

Example

var address = "TBCI2A67UQZAKCR6NS4JWAEICEIGEIM72G3MVW5S";

// Add hyphens to withcoin address
var fmtAddress = withcoin.utils.format.address(address); //TBCI2A-67UQZA-KCR6NS-4JWAEI-CEIGEI-M72G3M-VW5S

Format a withcoin quantity

Change a withcoin quantity into an array of values.

Quantity means the smallest unit (1.000000 XEM = 1'000'000)

Parameters

Example

var xemQuantity = 10003002; // Smallest unit for XEM

// Format quantity
var fmt = withcoin.utils.format.nemValue(xemQuantity)

var fmtAmount = fmt[0] + "." + fmt[1]; // 10.003002

Format a message object

Format hexadecimal payload contained in message objects.

Message objects also contains type:

Type 1: Plain message. Type 2: Encrypted message.

Parameters

Example

var msg = {
  "type": 1,
  "payload": "4e454d20697320617765736f6d652021"
}

// Format msg
var fmt = withcoin.utils.format.hexMessage(msg); // withcoin is awesome !

6 - Private Keys

A private key is a 64 or 66 characters hex string, looking like this:

// 64 characters hexadecimal private key
712cb1b773066cf572b6f271cb10be49b3e71ed24dd7b6a2ac876af9f3ad84e7

// 66 characters hexadecimal private key (always start with 00 in that case)
00d32b7c09e8747908b1ed9dbc893ff33987b2275bb3401cd5199f45b1bbbc7d75

6.1 - Create private keys

To obtain a private key, 4 choices are possible:

1) You can type yourself a random 64 hexadecimal string

2) Use the included PRNG:

// Create random bytes from PRNG
var rBytes = withcoin.crypto.nacl.randomBytes(32);

// Convert the random bytes to hex
var privateKey = withcoin.utils.convert.ua2hex(rBytes);

3) Create a private key from a passphrase:

// Derive a passphrase to get a private key
var privateKey = withcoin.crypto.helpers.derivePassSha(passphrase, 6000).priv;

4) Use a private key from another source.

6.2 - Create key pairs

Key pairs are objects representing accounts keys (private, secret and public) and are used to sign data or transactions.

Parameters

Example

// A funny but valid private key
var privateKey = "aaaaaaaaaaeeeeeeeeeebbbbbbbbbb5555555555dddddddddd1111111111aaee";

// Create a key pair
var keyPair = withcoin.crypto.keyPair.create(privateKey);

6.3 - Sign with key pair

To sign a transaction or any other data simply use the above keyPair object

Example

var signature = keyPair.sign(data);

6.4 - Extract public key from key pair

You can extract the public key from the keyPair object very easily

Example

var publicKey = keyPair.publicKey.toString();

6.5 - Verify a signature

To verify a signature you need the signer public key, the data that have been signed and the signature.

Parameters

Example

var signer = "0257b05f601ff829fdff84956fb5e3c65470a62375a1cc285779edd5ca3b42f6"
var signature = "392511e5b1d78e0991d4cb2a10037cc8be775e56d76b8157a4da726ccb44042e9b419084c09128ffe2a78fe78e2a19beb0e2f57e14b66c962187e61457bd9e09"
var data = "withcoin is awesome !";
// Verify
var result = withcoin.crypto.verifySignature(signer, data, signature);

• See examples/nodejs/verifySignature.js for node demonstration

7 - Addresses

Namespace: withcoin.model.address

Public methods:

• b32encode
• b32decode
• toAddress
• isFromNetwork
• isValid
• clean

Addresses are base32 string used to receive XEM. They look like this:

NAMOAV-HFVPJ6-FP32YP-2GCM64-WSRMKX-A5KKYW-WHPY NAMOAVHFVPJ6FP32YP2GCM64WSRMKXA5KKYWWHPY

The version without hyphens ("-") is the one we'll use in our queries and lower level processing. The formatted version is only for visual purposes.

Beginning of the address depend of the network:

• Mainnet (104): N

• Testnet (-104): T

7.1 - Convert public key to an address

var address = withcoin.model.address.toAddress(publicKey, networkId)

7.2 - Verify address validity

var isValid = withcoin.model.address.isValid(address);

7.3 - Verify if address is from given network

var isFromNetwork = withcoin.model.address.isFromNetwork(address, networkId);

7.4 - More

Consult src/model/address.js for more details

8 - Crypto Helpers

Namespace: withcoin.crypto.helpers

Public methods:

• toMobileKey
• derivePassSha
• passwordToPrivatekey
• checkAddress
• randomKey
• decrypt
• encrypt
• encodePrivKey
• encode
• decode

9 - Wallets

Namespace: withcoin.model.wallet

Public methods:

• createPRNG
• createBrain
• importPrivateKey

The SDK allow to create wallets 100% compatible with the Nano Wallet client (as BIP32 not implemented yet the client will ask for an upgrade).

Wallet can contain multiple accounts in an object of objects. The first account is the primary account and is labelled like this by default.

Every accounts objects but primary of brain wallets contains an encrypted private key. Brain wallets primary do not contains an encrypted private key because it is retrieved by the password / passphrase.

Each wallet has an algo property, it is needed to know how to decrypt the accounts.

Wallet files (.wlt) are just storing a wallet object as base 64 strings.

9.1 - Create simple wallets

withcoin.model.wallet.createPRNG create a wallet object with the primary account's private key generated from a PRNG

// Set a wallet name
var walletName = "QuantumMechanicsPRNG";

// Set a password
var password = "Something";

// Create PRNG wallet
var wallet = withcoin.model.wallet.createPRNG(walletName, password, withcoin.model.network.data.testnet.id);

9.2 - Create brain wallets

withcoin.model.wallet.createBrain create a wallet object with primary account's private key derived from a password/passphrase

// Set a wallet name
var walletName = "QuantumMechanicsBrain";

// Set a password/passphrase
var password = "Something another thing and something else";

// Create Brain wallet
var wallet = withcoin.model.wallet.createBrain(walletName, password, withcoin.model.network.data.testnet.id);

9.3 - Create private key wallets

withcoin.model.wallet.importPrivateKey create a wallet object with primary account's private key imported

// Set a wallet name
var walletName = "QuantumMechanicsImported";

// Set a password
var password = "Something";

// Set private key
var privateKey = "Private key to import";

// Create a private key wallet
var wallet = withcoin.model.wallet.importPrivateKey(walletName, password, privateKey, withcoin.model.network.data.testnet.id);

9.4 - Create wallet files

Create an empty file, name it walletName.wlt and put the base 64 string given by below code

// Convert stringified wallet object to word array
var wordArray = withcoin.crypto.js.enc.Utf8.parse(JSON.stringify(wallet));

// Word array to base64
var base64 = withcoin.crypto.js.enc.Base64.stringify(wordArray);

9.5 - Decrypt account in wallet

withcoin.crypto.helpers.passwordToPrivatekey is a function to decrypt an account into a wallet and return it's private key into the common object

// Create a common object
var common = withcoin.model.objects.create("common")("walletPassword/passphrase", "");

// Get the wallet account to decrypt
var walletAccount = wallet.accounts[index];

// Decrypt account private key 
withcoin.crypto.helpers.passwordToPrivatekey(common, walletAccount, wallet.algo);

// The common object now has a private key
console.log(common)