Herald + Node.js Script

import { Herald } from '@herald-protocol/sdk';

const herald = new Herald({
  apiKey: process.env.HERALD_API_KEY!,
});

interface LiquidationParams {
  wallet: string;
  positionId: string;
  healthFactor: number;
  debtAmount: number;
  asset: string;
}

async function sendLiquidationWarning(params: LiquidationParams) {
  const idempotencyKey = `liquidation_${params.positionId}_${Math.floor(Date.now() / 30000)}`;

  const result = await herald.notify({
    wallet: params.wallet,
    subject: `⚠️ Liquidation Warning — Health factor: ${params.healthFactor.toFixed(2)}`,
    body: [
      `Your lending position #${params.positionId} is approaching liquidation.`,
      ``,
      `Current health factor: ${params.healthFactor.toFixed(2)}`,
      `Outstanding debt: ${params.debtAmount} ${params.asset}`,
      ``,
      `Action required: Add collateral or repay debt immediately.`,
      `Threshold: 1.00`,
    ].join('\n'),
    category: 'defi',
    receipt: true,
    idempotencyKey,
  });

  console.log(`[Liquidation] Sent → ${result.notificationId} (${result.status})`);
  return result;
}

const params: LiquidationParams = {
  wallet: '7xR4mKp2nQwBvTsYjL8dHcFoEa3ZiXuW',
  positionId: 'POS-42069',
  healthFactor: 1.05,
  debtAmount: 50000,
  asset: 'SOL',
};

sendLiquidationWarning(params).catch(console.error);

import { Herald } from '@herald-protocol/sdk';

async function handleHeraldWebhook(
  rawBody: string,
  signatureHeader: string,
  webhookSecret: string,
) {
  const isValid = await Herald.verifyWebhookSignature(
    rawBody,
    signatureHeader,
    webhookSecret,
  );

  if (!isValid) {
    console.error('[Webhook] INVALID SIGNATURE — rejecting');
    return { status: 401, body: 'Invalid signature' };
  }

  const payload = JSON.parse(rawBody);

  switch (payload.event) {
    case 'delivery.confirmed':
      console.log(`[Webhook] ✅ ${payload.notificationId} delivered`);
      break;
    case 'delivery.failed':
      console.error(`[Webhook] ❌ ${payload.notificationId} failed: ${payload.error}`);
      break;
    case 'delivery.bounced':
      console.warn(`[Webhook] ⚠️ ${payload.notificationId} bounced`);
      break;
  }

  return { status: 200, body: 'ok' };
}