Arch TypeScript SDK

A TypeScript SDK for building, signing, and sending transactions on the Arch Network. This SDK provides low-level primitives for message creation, signature handling, and transaction submission, enabling developers to build custom workflows and applications on top of the Arch protocol.

Installation

npm install @saturnbtcio/arch-sdk

Quickstart Example

Below is a minimal example showing how to create a message, sign it, adjust the signature, and send an Arch transaction using this SDK.

import {
  ArchConnection,
  SanitizedMessageUtil,
  SignatureUtil,
  RpcConnection,
} from '@saturnbtcio/arch-sdk';

// 1. Set up a provider (e.g., RPC connection to an Arch node)
const provider = new RpcConnection({ nodeUrl: 'http://localhost:8899' });
const arch = ArchConnection(provider);

// 2. Prepare your instruction(s) (see Instruction type for structure)
const instructions = [/* ...your instructions here... */];
const payerPubkey = /* Uint8Array (32 bytes) */;
const recentBlockhash = /* Call the archRpc.getBestBlockhash */;

// 3. Create a SanitizedMessage
const message = SanitizedMessageUtil.createSanitizedMessage(
  instructions,
  payerPubkey,
  recentBlockhash
);

// 4. Hash the message and sign it (using your signing method)
const messageHash = SanitizedMessageUtil.hash(message); // Uint8Array
// Sign the message hash using your Bitcoin private key, producing a BIP322-compliant signature.
// You can use a wallet or library that supports BIP322 signing.
const signature = bip322Sign(privateKey, messageHash, addressType); // pseudocode

// 5. Adjust the signature to the required format
const adjustedSignature = SignatureUtil.adjustSignature(signature);

// 6. Build the transaction object
const transaction = {
  version: 1,
  signatures: [adjustedSignature],
  message,
};

// 7. Send the transaction
const txid = await arch.sendTransaction(transaction);
console.log('Arch transaction ID:', txid);

API Overview

Providers

• RpcConnection: Connects to an Arch node via HTTP.
• ArchConnection: Extends a provider with Arch-specific helpers (e.g., createNewAccount).

Message Creation

• SanitizedMessageUtil.createSanitizedMessage(instructions, payer, recentBlockhash)
  • Compiles instructions into a canonical message for signing and sending.
• SanitizedMessageUtil.hash(message)
  • Returns the hash (Uint8Array) of a sanitized message for signing.

Signature Utilities

• SignatureUtil.adjustSignature(signature: Uint8Array)
  • Normalizes a signature to the required 64-byte format for Arch transactions.

Transaction Structure

• RuntimeTransaction
  • { version: number, signatures: Uint8Array[], message: SanitizedMessage }

Sending Transactions

• arch.sendTransaction(transaction: RuntimeTransaction): Promise
  • Sends a transaction to the Arch network and returns the transaction ID.

Creating a New Account

• arch.createNewAccount(): Promise<{ privkey, pubkey, address }>
  • Generates a new keypair and returns the address, pubkey, and privkey.

Types

• Instruction: { program_id, accounts, data }
• SanitizedMessage: { header, account_keys, recent_blockhash, instructions }
• Signature: Uint8Array (64 bytes)
• RuntimeTransaction: { version, signatures, message }

System Instruction Helpers

The SDK provides low-level helper functions for constructing system instructions compatible with the Arch blockchain. These helpers serialize instruction data in a format expected by the on-chain Rust programs, making it easy to create, transfer, and manage accounts from TypeScript.

createAccount

Creates a new account on the blockchain.

Parameters:

• fromPubkey: Pubkey — Funding account public key (signer, writable)
• toPubkey: Pubkey — New account public key (signer, writable)
• lamports: bigint — Number of lamports to transfer to the new account
• space: bigint — Number of bytes of memory to allocate
• owner: Pubkey — Program that will own the new account

Example:

const ix = createAccount(funder, newAccount, 1000n, 128n, ownerProgramId);

---

createAccountWithAnchor

Creates a new account and anchors it to a specific UTXO (e.g., for Bitcoin integration).

Parameters:

• fromPubkey: Pubkey — Funding account public key (signer, writable)
• toPubkey: Pubkey — New account public key (signer, writable)
• lamports: bigint — Number of lamports to transfer
• space: bigint — Number of bytes of memory to allocate
• owner: Pubkey — Program that will own the new account
• txid: string — 64-character hex string of the UTXO transaction ID
• vout: number — Output index of the UTXO

Example:

const ix = createAccountWithAnchor(
  funder,
  newAccount,
  1000n,
  128n,
  ownerProgramId,
  'aabbcc...ff', // 64-char hex string
  0,
);

---

transfer

Transfers lamports from one account to another.

Parameters:

• fromPubkey: Pubkey — Sender account public key (signer, writable)
• toPubkey: Pubkey — Recipient account public key (writable)
• lamports: bigint — Amount to transfer

Example:

const ix = transfer(sender, recipient, 500n);

---

assign

Assigns a new owner (program) to an account.

Parameters:

• pubkey: Pubkey — Account to reassign (signer, writable)
• owner: Pubkey — New owner program public key

Example:

const ix = assign(account, newOwnerProgramId);

---

allocate

Allocates space in an account without funding it.

Parameters:

• pubkey: Pubkey — Account to allocate space for (signer, writable)
• space: bigint — Number of bytes to allocate

Example:

const ix = allocate(account, 256n);

---

Usage Note: After constructing an instruction with these helpers, use the SDK's serialization utilities (see above) to serialize and send the instruction as part of a transaction.

Example: Creating and Sending a Transaction

import {
  ArchConnection,
  SanitizedMessageUtil,
  SignatureUtil,
  RpcConnection,
  // ...other imports
} from '@saturnbtcio/arch-sdk';

// Set up provider and arch connection
const provider = new RpcConnection({ nodeUrl: 'http://localhost:8899' });
const arch = ArchConnection(provider);

// Example instruction (replace with your actual data)
const instruction = {
  program_id: new Uint8Array(32), // 32-byte program ID
  accounts: [
    {
      pubkey: new Uint8Array(32), // 32-byte pubkey
      is_signer: true,
      is_writable: true,
    },
  ],
  data: new Uint8Array([1, 2, 3]), // Your instruction data
};

const payerPubkey = new Uint8Array(32); // Replace with your payer pubkey
const recentBlockhash = '...'; // Call the archRpc.getBestBlockhash

const message = SanitizedMessageUtil.createSanitizedMessage(
  [instruction],
  payerPubkey,
  recentBlockhash,
);

const messageHash = SanitizedMessageUtil.hash(message);
// Sign the message hash with your Bitcoin private key using the BIP322 standard.
// (You must use a wallet or library that supports BIP322 message signing.)
const signature = bip322Sign(privateKey, messageHash, addressType); // pseudocode
const adjustedSignature = SignatureUtil.adjustSignature(signature);

const transaction = {
  version: 1,
  signatures: [adjustedSignature],
  message,
};

const txid = await arch.sendTransaction(transaction);
console.log('Arch transaction ID:', txid);

Advanced Topics

• Multiple Signers: Add multiple signatures to the signatures array in the transaction.
• Custom Providers: Implement the Provider interface for custom transport or signing logic.

Troubleshooting

• Ensure all public keys and signatures are 32 and 64 bytes respectively.
• Use SignatureUtil.adjustSignature to normalize signatures from different signing libraries.
• Check node connectivity and blockhash freshness if transactions fail to send.

WebSocket Client: Real-Time Event Subscriptions

The SDK provides a WebSocket client for subscribing to real-time events from the Arch network, such as new blocks, transactions, account updates, and more.

Features

• Connect/disconnect to a WebSocket server
• Subscribe to event topics (block, transaction, account update, etc.)
• Filter events by custom criteria
• Add/remove listeners for events
• Automatic reconnection with backoff strategies

Event Topics

• block: New block events
• transaction: Transaction status updates
• account_update: Account state changes
• rolledback_transactions, reapplied_transactions, dkg: Advanced protocol events

Configuration Options

You can customize the WebSocket client by passing a configuration object to the constructor:

interface WebSocketClientOptions {
  url: string; // (Required) WebSocket server URL
  maxReconnectAttempts?: number; // Max reconnection attempts (default: 5)
  backoffStrategy?: BackoffStrategy; // Reconnection backoff strategy (see below)
  autoReconnect?: boolean; // Enable auto-reconnect (default: false)
  timeout?: number; // Connection timeout in ms (default: 20000)
  transports?: string[]; // Socket.IO transports (default: ['websocket', 'polling'])
  forceNew?: boolean; // Force new connection (default: true)
  multiplex?: boolean; // Enable multiplexing (default: false)
}

interface BackoffStrategy {
  type: 'constant' | 'linear' | 'exponential'; // Strategy type
  initial?: number; // Initial delay in ms (default: 1000)
  factor?: number; // Growth factor for exponential (default: 2)
  maxDelay?: number; // Max delay in ms (default: 30000)
  step?: number; // Step size for linear (optional)
  jitter?: number; // Jitter as a fraction (default: 0.2)
}

Defaults:

• maxReconnectAttempts: 5
• autoReconnect: false
• timeout: 20000
• transports: ['websocket', 'polling']
• forceNew: true
• multiplex: false
• backoffStrategy: Exponential (initial: 1000ms, factor: 2, maxDelay: 30000ms, jitter: 0.2)

Example

const client = new ArchWebSocketClient({
  url: 'ws://localhost:3001',
  autoReconnect: true,
  maxReconnectAttempts: 10,
  timeout: 15000,
  transports: ['websocket'],
  backoffStrategy: {
    type: 'exponential',
    initial: 500,
    factor: 2,
    maxDelay: 20000,
    jitter: 0.1,
  },
});

Example Usage

import { ArchWebSocketClient } from '@saturnbtcio/arch-sdk';
import { EventTopic } from '@saturnbtcio/arch-sdk/websocket-client/types/events';

const client = new ArchWebSocketClient({ url: 'ws://localhost:3001' });

// Connect to the server
await client.connect();

// Subscribe to new block events
const blockCallback = async (event) => {
  console.log('New block:', event.hash, event.timestamp);
};
await client.subscribe(EventTopic.Block, blockCallback);

// Subscribe to transaction events with a filter
const txCallback = async (event) => {
  console.log('Transaction update:', event.hash, event.status);
};
await client.subscribe(EventTopic.Transaction, txCallback, {
  status: 'Processed',
});

// Add an additional listener for account updates
client.on(EventTopic.AccountUpdate, (event) => {
  console.log('Account updated:', event.account);
});

// Disconnect when done
await client.disconnect();

Filters

You can filter events by fields such as status, programIds, block hash, etc. (see EventFilter, TransactionFilter, BlockFilter).

Reconnection

The client supports automatic reconnection with customizable backoff strategies:

client.setReconnectOptions(
  true,
  /* strategy */ 'exponential',
  /* maxAttempts */ 5,
);

Event Types

See the SDK source for all event interfaces (e.g., BlockEvent, TransactionEvent, AccountUpdateEvent).

---

Wallet Types

The SDK and related packages define types for representing user wallets, UTXOs, and collections:

interface Wallet {
  address: string;
  balance: bigint;
  utxos: Array<CollectionUtxo>;
}

interface CollectionUtxo {
  // UTXO details
  collectionStatuses: Array<CollectionAmount>;
  hasInscription: boolean;
}

interface CollectionAmount {
  id: string;
  type: 'rune' | 'btc';
  amount: bigint;
}

These types are useful for wallet management, UTXO selection, and integration with pool or transaction logic.

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