Node.js Usage

This guide shows how to use the SatsTerminal Borrow SDK in a Node.js environment.

Setup

Installation

npm install @satsterminal-sdk/borrow

Environment Variables

# .env
SATSTERMINAL_API_KEY=your-api-key
SATSTERMINAL_BASE_URL=https://api.satsterminal.com
BTC_ADDRESS=bc1q...
BTC_PRIVATE_KEY=... # For signing (use secure key management in production)

Basic Configuration

import { BorrowSDK, ChainType } from '@satsterminal-sdk/borrow';
import * as bitcoin from 'bitcoinjs-lib';
import * as ecc from 'tiny-secp256k1';
import { ECPairFactory } from 'ecpair';

const ECPair = ECPairFactory(ecc);

// Load environment variables
const config = {
  apiKey: process.env.SATSTERMINAL_API_KEY!,
  baseUrl: process.env.SATSTERMINAL_BASE_URL!,
  btcAddress: process.env.BTC_ADDRESS!,
  btcPrivateKey: process.env.BTC_PRIVATE_KEY!
};

// Create key pair for signing
const keyPair = ECPair.fromWIF(config.btcPrivateKey);

// Create SDK instance
const sdk = new BorrowSDK({
  apiKey: config.apiKey,
  baseUrl: config.baseUrl,
  chain: ChainType.ARBITRUM,
  wallet: {
    address: config.btcAddress,
    signMessage: async (message: string) => {
      // Sign message with Bitcoin private key
      const signature = keyPair.sign(
        bitcoin.crypto.sha256(Buffer.from(message))
      );
      return signature.toString('base64');
    }
  },
  // Use memory storage in Node.js
  storage: {
    _data: new Map<string, string>(),
    getItem(key: string) { return this._data.get(key) || null; },
    setItem(key: string, value: string) { this._data.set(key, value); },
    removeItem(key: string) { this._data.delete(key); },
    clear() { this._data.clear(); }
  }
});

CLI Application

// cli.ts
import { BorrowSDK, ChainType } from '@satsterminal-sdk/borrow';
import { Command } from 'commander';

const program = new Command();

let sdk: BorrowSDK;

async function initSDK() {
  sdk = new BorrowSDK({
    apiKey: process.env.API_KEY!,
    baseUrl: process.env.BASE_URL!,
    chain: ChainType.ARBITRUM,
    wallet: {
      address: process.env.BTC_ADDRESS!,
      signMessage: async (msg) => signWithWallet(msg)
    }
  });
  await sdk.setup();
  console.log('SDK initialized');
}

program
  .name('borrow-cli')
  .description('SatsTerminal Borrow CLI')
  .version('1.0.0');

program
  .command('status')
  .description('Show current status')
  .action(async () => {
    await initSDK();
    console.log('User Status:', sdk.userStatus);
  });

program
  .command('quote')
  .description('Get loan quotes')
  .option('-c, --collateral <btc>', 'Collateral amount in BTC', '0.1')
  .option('-l, --loan <usd>', 'Loan amount in USD', '5000')
  .option('--ltv <percent>', 'Loan-to-value ratio', '70')
  .action(async (options) => {
    await initSDK();

    const quotes = await sdk.getQuotes({
      collateralAmount: options.collateral,
      loanAmount: options.loan,
      ltv: parseInt(options.ltv)
    });

    console.log('\nAvailable Quotes:');
    quotes.forEach((q, i) => {
      console.log(`${i + 1}. ${q.protocol} - APY: ${q.borrowApy.variable}%`);
    });
  });

program
  .command('borrow')
  .description('Get a loan')
  .option('-c, --collateral <btc>', 'Collateral amount in BTC', '0.1')
  .option('-l, --loan <usd>', 'Loan amount in USD', '5000')
  .action(async (options) => {
    await initSDK();

    console.log('Starting loan...');

    await sdk.getLoan({
      collateralBTC: parseFloat(options.collateral),
      loanAmountUSD: parseFloat(options.loan),
      onStatusUpdate: (status) => {
        console.log(`[${status.step}] ${status.label}`);
      },
      onDepositReady: (info) => {
        console.log('\n=== DEPOSIT REQUIRED ===');
        console.log(`Amount: ${info.amountBTC} BTC`);
        console.log(`Address: ${info.address}`);
        console.log('========================\n');
      },
      onComplete: () => {
        console.log('\nLoan complete!');
        process.exit(0);
      },
      onError: (error) => {
        console.error('\nError:', error);
        process.exit(1);
      }
    });
  });

program
  .command('history')
  .description('Show loan history')
  .option('-s, --status <status>', 'Filter by status (active|pending|all)', 'all')
  .action(async (options) => {
    await initSDK();

    const history = await sdk.getLoanHistory({
      status: options.status as 'active' | 'pending' | 'all'
    });

    console.log(`\nLoan History (${history.pagination.totalTransactions} total):\n`);

    history.transactions.forEach((tx) => {
      console.log(`ID: ${tx.id}`);
      console.log(`  Type: ${tx.type}`);
      console.log(`  Amount: ${tx.amount} ${tx.currency}`);
      console.log(`  Status: ${tx.status}`);
      console.log(`  Date: ${new Date(tx.timestamp).toLocaleString()}`);
      console.log('');
    });
  });

program
  .command('positions')
  .description('Show wallet positions')
  .action(async () => {
    await initSDK();

    const positions = await sdk.getWalletPositions();

    console.log('\nWallet Positions:\n');

    let totalValue = 0;
    positions.data.forEach((p) => {
      const symbol = p.attributes.fungible_info?.symbol || 'Unknown';
      const amount = p.attributes.quantity.float;
      const value = p.attributes.value || 0;
      totalValue += value;

      console.log(`${symbol}: ${amount.toFixed(4)} ($${value.toFixed(2)})`);
    });

    console.log(`\nTotal Value: $${totalValue.toFixed(2)}`);
  });

program
  .command('repay <loanId> <amount>')
  .description('Repay a loan')
  .option('-w, --withdraw <btc>', 'Withdraw collateral')
  .option('-a, --address <btc>', 'BTC address for withdrawal')
  .action(async (loanId, amount, options) => {
    await initSDK();

    console.log(`Repaying ${amount} USD...`);

    await sdk.repay(loanId, amount, {
      collateralToWithdraw: options.withdraw,
      userBtcWithdrawAddress: options.address,
      trackWorkflow: true,
      callbacks: {
        onStatusUpdate: (status) => {
          console.log(`[${status.step}] ${status.label}`);
        },
        onComplete: () => {
          console.log('\nRepayment complete!');
          process.exit(0);
        },
        onError: (error) => {
          console.error('\nError:', error);
          process.exit(1);
        }
      }
    });
  });

program.parse();

Automation Scripts

Automated Loan Monitoring

// monitor.ts
import { BorrowSDK, ChainType, UserTransaction } from '@satsterminal-sdk/borrow';

async function monitorLoans(sdk: BorrowSDK) {
  console.log('Starting loan monitor...');

  setInterval(async () => {
    try {
      const history = await sdk.getLoanHistory({ status: 'active' });

      for (const loan of history.transactions) {
        const collateral = await sdk.getLoanCollateralInfo(loan.id);

        if (collateral) {
          const healthRatio =
            parseFloat(collateral.availableCollateral) /
            parseFloat(collateral.totalDebt);

          console.log(`Loan ${loan.id.slice(0, 8)}... Health: ${healthRatio.toFixed(2)}`);

          // Alert if health is low
          if (healthRatio < 1.2) {
            console.warn(`⚠️ LOW HEALTH: Loan ${loan.id} health is ${healthRatio.toFixed(2)}`);
            // Send notification (email, Slack, etc.)
            await sendAlert({
              type: 'low_health',
              loanId: loan.id,
              health: healthRatio
            });
          }
        }
      }
    } catch (error) {
      console.error('Monitor error:', error);
    }
  }, 60000); // Check every minute
}

Batch Operations

// batch.ts
import { BorrowSDK, ChainType } from '@satsterminal-sdk/borrow';

async function batchRepay(
  sdk: BorrowSDK,
  loans: Array<{ id: string; amount: string }>
) {
  console.log(`Processing ${loans.length} repayments...`);

  const results: Array<{ id: string; success: boolean; error?: string }> = [];

  for (const loan of loans) {
    try {
      console.log(`Repaying loan ${loan.id}...`);

      await sdk.repay(loan.id, loan.amount, {
        trackWorkflow: true,
        callbacks: {
          onComplete: () => {
            console.log(`✓ Loan ${loan.id} repaid`);
          }
        }
      });

      results.push({ id: loan.id, success: true });
    } catch (error) {
      console.error(`✗ Loan ${loan.id} failed:`, error);
      results.push({
        id: loan.id,
        success: false,
        error: error instanceof Error ? error.message : 'Unknown error'
      });
    }

    // Rate limiting
    await new Promise(r => setTimeout(r, 2000));
  }

  // Summary
  const successful = results.filter(r => r.success).length;
  console.log(`\nCompleted: ${successful}/${loans.length} successful`);

  return results;
}

Scheduled Tasks

// scheduler.ts
import cron from 'node-cron';
import { BorrowSDK, ChainType } from '@satsterminal-sdk/borrow';

async function setupScheduler(sdk: BorrowSDK) {
  // Check positions every hour
  cron.schedule('0 * * * *', async () => {
    console.log('Running hourly position check...');
    const positions = await sdk.getWalletPositions();
    // Process positions
  });

  // Check loan health every 15 minutes
  cron.schedule('*/15 * * * *', async () => {
    console.log('Running health check...');
    const history = await sdk.getLoanHistory({ status: 'active' });

    for (const loan of history.transactions) {
      const info = await sdk.getLoanCollateralInfo(loan.id);
      // Check health and alert if needed
    }
  });

  // Daily summary at 9 AM
  cron.schedule('0 9 * * *', async () => {
    console.log('Generating daily summary...');
    const portfolio = await sdk.getWalletPortfolio();
    const history = await sdk.getLoanHistory({ status: 'all' });
    // Generate and send report
  });

  console.log('Scheduler started');
}

API Server

// server.ts
import express from 'express';
import { BorrowSDK, ChainType } from '@satsterminal-sdk/borrow';

const app = express();
app.use(express.json());

// SDK instances per user (in production, use proper session management)
const sdkInstances = new Map<string, BorrowSDK>();

function getSDK(userId: string): BorrowSDK {
  if (!sdkInstances.has(userId)) {
    throw new Error('SDK not initialized for user');
  }
  return sdkInstances.get(userId)!;
}

// Initialize SDK for user
app.post('/api/init', async (req, res) => {
  try {
    const { userId, btcAddress, signature } = req.body;

    const sdk = new BorrowSDK({
      apiKey: process.env.API_KEY!,
      baseUrl: process.env.BASE_URL!,
      chain: ChainType.ARBITRUM,
      wallet: {
        address: btcAddress,
        signMessage: async () => signature // Pre-signed
      }
    });

    await sdk.setup();
    sdkInstances.set(userId, sdk);

    res.json({ success: true, userStatus: sdk.userStatus });
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// Get quotes
app.post('/api/quotes', async (req, res) => {
  try {
    const sdk = getSDK(req.body.userId);
    const quotes = await sdk.getQuotes(req.body.params);
    res.json({ quotes });
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// Get loan history
app.get('/api/loans/:userId', async (req, res) => {
  try {
    const sdk = getSDK(req.params.userId);
    const history = await sdk.getLoanHistory({
      status: (req.query.status as any) || 'all'
    });
    res.json(history);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// Get positions
app.get('/api/positions/:userId', async (req, res) => {
  try {
    const sdk = getSDK(req.params.userId);
    const positions = await sdk.getWalletPositions();
    res.json(positions);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// Health check endpoint
app.get('/health', (req, res) => {
  res.json({ status: 'ok', instances: sdkInstances.size });
});

app.listen(3000, () => {
  console.log('API server running on port 3000');
});

Best Practices

Error Handling

import { BorrowSDKError, ApiError } from '@satsterminal-sdk/borrow';

async function safeOperation<T>(
  operation: () => Promise<T>,
  retries = 3
): Promise<T> {
  let lastError: Error | undefined;

  for (let i = 0; i < retries; i++) {
    try {
      return await operation();
    } catch (error) {
      lastError = error as Error;

      if (error instanceof ApiError) {
        if (error.statusCode === 429) {
          // Rate limited - wait and retry
          await new Promise(r => setTimeout(r, 5000 * (i + 1)));
          continue;
        }
        if (error.statusCode && error.statusCode >= 500) {
          // Server error - retry
          await new Promise(r => setTimeout(r, 1000 * (i + 1)));
          continue;
        }
      }

      // Non-retryable error
      throw error;
    }
  }

  throw lastError;
}

Logging

import winston from 'winston';

const logger = winston.createLogger({
  level: 'info',
  format: winston.format.combine(
    winston.format.timestamp(),
    winston.format.json()
  ),
  transports: [
    new winston.transports.File({ filename: 'error.log', level: 'error' }),
    new winston.transports.File({ filename: 'combined.log' })
  ]
});

const sdk = new BorrowSDK({
  // ...config
  logger: {
    debug: (msg) => logger.debug(msg),
    info: (msg) => logger.info(msg),
    warn: (msg) => logger.warn(msg),
    error: (msg) => logger.error(msg)
  }
});

Graceful Shutdown

let sdk: BorrowSDK;

process.on('SIGTERM', async () => {
  console.log('Shutting down...');

  if (sdk) {
    sdk.clearSession();
  }

  process.exit(0);
});

process.on('uncaughtException', (error) => {
  console.error('Uncaught exception:', error);

  if (sdk) {
    sdk.clearSession();
  }

  process.exit(1);
});

Overview

Suite

Swaps

Borrow

Nodejs usage

Node.js Usage

Setup

Installation

Environment Variables

Basic Configuration

CLI Application

Automation Scripts

Automated Loan Monitoring

Batch Operations

Scheduled Tasks

API Server

Best Practices

Error Handling

Logging

Graceful Shutdown

Overview

Suite

Swaps

Borrow

​Node.js Usage

​Setup

​Installation

​Environment Variables

​Basic Configuration

​CLI Application

​Automation Scripts

​Automated Loan Monitoring

​Batch Operations

​Scheduled Tasks

​API Server

​Best Practices

​Error Handling

​Logging

​Graceful Shutdown

Node.js Usage

Setup

Installation

Environment Variables

Basic Configuration

CLI Application

Automation Scripts

Automated Loan Monitoring

Batch Operations

Scheduled Tasks

API Server

Best Practices

Error Handling

Logging

Graceful Shutdown