XpringKit 3.2.0

XpringKit 3.2.0

Maintained by Keefer Taylor, Doug Purdy, Amie Corso, Noah Kramer.



 
Depends on:
Alamofire~> 4.9.0
BigInt~> 5.0.0
SwiftGRPC~> 0.9.1
SwiftProtobuf~> 1.5.0
 

XpringKit 3.2.0

  • By
  • Xpring Engineering

CircleCI CodeCov

XpringKit

XpringKit is the Swift client side library of the Xpring SDK.

Features

XpringKit provides the following features:

  • Wallet generation and derivation (Seed or HD Wallet based)
  • Address validation
  • Account balance retrieval
  • Sending XRP payments

Installation

Client Side Library

Carthage

XpringKit is available via Carthage. Simply add the following to your Cartfile:

github "xpring-eng/XpringKit"

CocoaPods

XpringKit is available via CocoaPods. Simply add the following to your Podfile:

pod 'XpringKit'

rippled Node

Xpring SDK needs to communicate with a rippled node which has gRPC enabled. Consult the rippled documentation for details on how to build your own node.

To get developers started right away, Xpring currently provides nodes:

# Testnet
test.xrp.xpring.io:50051

# Mainnet
main.xrp.xpring.io:50051

Hermes Node

Xpring SDK's IlpClient needs to communicate with Xpring's ILP infrastructure through an instance of Hermes.

In order to connect to the Hermes instance that Xpring currently operates, you will need to create an ILP wallet here

Once your wallet has been created, you can use the gRPC URL specified in your wallet, as well as your access token to check your balance and send payments over ILP.

Usage: XRP

Note: Xpring SDK only works with the X-Address format. For more information about this format, see the Utilities section and http://xrpaddress.info.

Wallets

A wallet is a fundamental model object in XpringKit which provides key management, address derivation, and signing functionality. Wallets can be derived from either a seed or a mnemonic and derivation path. You can also choose to generate a new random HD wallet.

Wallet Derivation

XpringKit can derive a wallet from a seed or it can derive a hierarchical deterministic wallet (HDWallet) from a mnemonic and derivation path.

Hierarchical Deterministic Wallets

A hierarchical deterministic wallet is created using a mnemonic and a derivation path. Simply pass the mnemonic and derivation path to the wallet generation function. Note that you can omit the derivation path and have a default path be used instead.

import XpringKit

let mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"

let hdWallet1 = Wallet.generateWalletFromMnemonic(mnemonic: mnemonic)! // Has default derivation path
let hdWallet2 = Wallet(mnemonic: mnemonic, derivationPath: Wallet.defaultDerivationPath)! // Same as hdWallet1

let hdWallet = Wallet(mnemonic: mnemonic, derivationPath: "m/44'/144'/0'/0/1"); // Wallet with custom derivation path.
Seed Based Wallets

You can construct a seed based wallet by passing a base58check encoded seed string.

import XpringKit

let seedWallet = Wallet(seed: "snRiAJGeKCkPVddbjB3zRwiYDBm1M")!

Wallet Generation

XpringKit can generate a new and random HD Wallet. The result of a wallet generation call is a tuple which contains the following:

  • A randomly generated mnemonic
  • The derivation path used, which is the default path
  • A reference to the new wallet
import XpringKit

// Generate a random wallet.
let generationResult = Wallet.generateRandomWallet()!
let newWallet = generationResult.wallet

// Wallet can be recreated with the artifacts of the initial generation.
let copyOfNewWallet = Wallet(mnemonic: generationResult.mnemonic, derivationPath: generationResult.derivationPath)

Wallet Properties

A generated wallet can provide its public key, private key, and address on the XRP ledger.

import XpringKit

let mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about";

let wallet = Wallet(mnemonic: mnemonic)!

print(wallet.address) // XVMFQQBMhdouRqhPMuawgBMN1AVFTofPAdRsXG5RkPtUPNQ
print(wallet.publicKey) // 031D68BC1A142E6766B2BDFB006CCFE135EF2E0E2E94ABB5CF5C9AB6104776FBAE
print(wallet.privateKey) // 0090802A50AA84EFB6CDB225F17C27616EA94048C179142FECF03F4712A07EA7A4

Signing / Verifying

A wallet can also sign and verify arbitrary hex messages. Generally, users should use the functions on XRPClient to perform cryptographic functions rather than using these low level APIs.

import XpringKit

let mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"
let message = "deadbeef";

let wallet = Wallet(mnemonic: mnemonic)!

let signature = wallet.sign(message)
wallet.verify(message, signature); // true

XRPClient

XRPClient is a gateway into the XRP Ledger. XRPClient is initialized with a single parameter, which is the URL of the remote adapter (see: ‘Server Side Component’ section above).

import XpringKit

let remoteURL = "test.xrp.xpring.io:50051"; // Testnet URL, use main.xrp.xpring.io:50051 for Mainnet
let xrpClient = XRPClient(grpcURL: remoteURL, network: XRPLNetwork.test)

Retrieving a Balance

An XRPClient can check the balance of an account on the XRP Ledger.

import XpringKit

let remoteURL = "test.xrp.xpring.io:50051"; // Testnet URL, use main.xrp.xpring.io:50051 for Mainnet
let xrpClient = XRPClient(grpcURL: remoteURL, network: XRPLNetwork.test)

let address = "XVMFQQBMhdouRqhPMuawgBMN1AVFTofPAdRsXG5RkPtUPNQ"

let balance = try! xrpClient.getBalance(for: address)
print(balance) // Logs a balance in drops of XRP

Checking Payment Status

An XRPClient can check the status of an payment on the XRP Ledger.

This method can only determine the status of payment transactions which do not have the partial payment flag (tfPartialPayment) set.

XpringKit returns the following transaction states:

  • succeeded: The transaction was successfully validated and applied to the XRP Ledger.
  • failed: The transaction was successfully validated but not applied to the XRP Ledger. Or the operation will never be validated.
  • pending: The transaction has not yet been validated, but may be validated in the future.
  • unknown: The transaction status could not be determined, the hash represented a non-payment type transaction, or the hash represented a transaction with the tfPartialPayment flag set.

Note: For more information, see Reliable Transaction Submission and Transaction Results.

These states are determined by the TransactionStatus enum.

import XpringKit

let remoteURL = "test.xrp.xpring.io:50051"; // Testnet URL, use main.xrp.xpring.io:50051 for Mainnet
let xrpClient = XRPClient(grpcURL: remoteURL, network: XRPLNetwork.test)

let transactionHash = "9FC7D277C1C8ED9CE133CC17AEA9978E71FC644CE6F5F0C8E26F1C635D97AF4A"

let transactionStatus = xrpClient.paymentStatus(for: transactionHash) // TransactionStatus.succeeded

Note: The example transactionHash may lead to a "Transaction not found." error because the TestNet is regularly reset, or the accessed node may only maintain one month of history. Recent transaction hashes can be found in the XRP Ledger Explorer .

Retrieve specific payment

An XRPClient can retrieve a specific payment transaction by hash.

import XpringKit 

let remoteURL = "alpha.test.xrp.xpring.io:50051"; // TestNet URL, use alpha.xrp.xpring.io:50051 for Mainnet
let xrpClient = XRPClient(grpcURL: remoteURL, network: XRPLNetwork.test)

let transactionHash = "9FC7D277C1C8ED9CE133CC17AEA9978E71FC644CE6F5F0C8E26F1C635D97AF4A"
let payment = try! xrpClient.getPayment(for: transactionHash)

Note: The example transactionHash may lead to a "Transaction not found." error because the TestNet is regularly reset, or the accessed node may only maintain one month of history. Recent transaction hashes can be found in the XRP Ledger Explorer .

Payment history

An XRPClient can return payments to and from an account.

import XpringKit 

let remoteURL = "alpha.test.xrp.xpring.io:50051"; // TestNet URL, use alpha.xrp.xpring.io:50051 for Mainnet
let xrpClient = XRPClient(grpcURL: remoteURL, network: XRPLNetwork.test)

let address = "XVMFQQBMhdouRqhPMuawgBMN1AVFTofPAdRsXG5RkPtUPNQ"

let transactions = try! xrpClient.paymentHistory(for: address)

Sending XRP

An XRPClient can send XRP to other accounts on the XRP Ledger.

Note: The payment operation will block the calling thread until the operation reaches a definitive and irreversible success or failure state.

import XpringKit

let remoteURL = "test.xrp.xpring.io:50051"; // TestNet URL, use main.xrp.xpring.io:50051 for Mainnet
let xrpClient = XRPClient(grpcURL: remoteURL, network: XRPLNetwork.test)

// Wallet which will send XRP
let generationResult = Wallet.generateRandomWallet()!
let senderWallet = generationResult.wallet

// Destination address.
let address = "X7u4MQVhU2YxS4P9fWzQjnNuDRUkP3GM6kiVjTjcQgUU3Jr"

// Amount of XRP to send, in drops.
let amount: UInt64 = 10

let transactionHash = try! xrpClient.send(amount, to: destinationAddress, from: senderWallet)

Note: The above example will yield an "Account not found." error because the randomly generated wallet contains no XRP.

Utilities

Address validation

The Utils object provides an easy way to validate addresses.

import XpringKit

let rippleClassicAddress = "rnysDDrRXxz9z66DmCmfWpq4Z5s4TyUP3G"
let rippleXAddress = "X7jjQ4d6bz1qmjwxYUsw6gtxSyjYv5iWPqPEjGqqhn9Woti"
let bitcoinAddress = "1DiqLtKZZviDxccRpowkhVowsbLSNQWBE8"

Utils.isValid(address: rippleAddress); // returns true
Utils.isValid(address: bitcoinAddress); // returns false

You can also validate if an address is an X-Address or a classic address.

import XpringKit

let rippleClassicAddress = "rnysDDrRXxz9z66DmCmfWpq4Z5s4TyUP3G"
let rippleXAddress = "X7jjQ4d6bz1qmjwxYUsw6gtxSyjYv5iWPqPEjGqqhn9Woti"
let bitcoinAddress = "1DiqLtKZZviDxccRpowkhVowsbLSNQWBE8"

Utils.isValidXAddress(address: rippleClassicAddress); // returns false
Utils.isValidXAddress(address: rippleXAddress); // returns true
Utils.isValidXAddress(address: bitcoinAddress); // returns false

Utils.isValidClassicAddress(address: rippleClassicAddress); // returns true
Utils.isValidClassicAddress(address: rippleXAddress); // returns false
Utils.isValidClassicAddress(address: bitcoinAddress); // returns false

X-Address Encoding

You can encode and decode X-Addresses with the SDK.

import XpringKit

let rippleClassicAddress = "rnysDDrRXxz9z66DmCmfWpq4Z5s4TyUP3G"
let tag: UInt32 = 12345;

// Encode an X-Address.
let xAddress = Utils.encode(classicAddress: address, tag: tag) // X7jjQ4d6bz1qmjwxYUsw6gtxSyjYv5xRB7JM3ht8XC4P45P

// Decode an X-Address.
let classicAddressTuple = Utils.decode(xAddress: address)!
print(classicAddressTuple.classicAddress); // rnysDDrRXxz9z66DmCmfWpq4Z5s4TyUP3G
print(classicAddressTuple.tag); // 12345

Usage: ILP

ILPClient

ILPClient is the main interface into the ILP network. ILPClient must be initialized with the URL of a Hermes instance. This can be found in your wallet.

All calls to ILPClient must pass an access token, which can be generated in your wallet.

import XpringKit

let grpcUrl = "hermes-grpc-test.xpring.dev" // TestNet Hermes URL
let ilpClient = ILPClient(grpcURL: grpcUrl)

Retreiving a Balance

An ILPClient can check the balance of an account on a connector.

import XpringKit

let grpcUrl = "hermes-grpc-test.xpring.dev" // TestNet Hermes URL
let ilpClient = ILPClient(grpcURL: grpcUrl)

let getBalance = try ilpClient.getBalance(for: "demo_user", withAuthorization: "2S1PZh3fEKnKg") // Just a demo user on Testnet
print("Net balance was \(getBalance.netBalance) with asset scale \(getBalance.assetScale)")

Sending a Payment

An ILPClient can send an ILP payment to another ILP address by supplying a Payment Pointer and a sender's account ID.

import XpringKit

let grpcUrl = "hermes-grpc-test.xpring.dev" // TestNet Hermes URL
let ilpClient = ILPClient(grpcURL: grpcUrl)

let paymentRequest = PaymentRequest(
    100, 
    to: "$xpring.money/demo_receiver", 
    from: "demo_user"
)
let payment = try ilpClient.sendPayment(
    paymentRequest,
    withAuthorization: "2S1PZh3fEKnKg"
)

Contributing

Pull requests are welcome! To get started with building this library and opening pull requests, please see contributing.md.

Thank you to all the users who have contributed to this library!

License

Xpring SDK is available under the MIT license. See the LICENSE file for more info.