Serverless-обработчик вебхуков с ретраями, логами и фоновыми задачами

import Stripe from 'stripe';

const stripe = new Stripe(process.env.STRIPE_SECRET_KEY);

export async function handler(event) {
  const rawBody = event.body ?? '';
  const sig = event.headers['stripe-signature'] ?? '';
  let evt;
  try {
    evt = stripe.webhooks.constructEvent(rawBody, sig, process.env.STRIPE_WEBHOOK_SECRET);
  } catch (err) {
    return { statusCode: 400, body: `Webhook Error: ${err.message}` };
  }
  const isNew = await db.upsertWebhookEvent(evt.id, evt.type);
  if (!isNew) return { statusCode: 200, body: 'duplicate' };
  await global.durable.startNew('stripe-fulfillment', undefined, { eventId: evt.id, type: evt.type, data: evt.data.object });
  return { statusCode: 200, body: 'accepted' };
}

import { createHmac, timingSafeEqual } from 'node:crypto';

export async function handler(event) {
  const body = event.body ?? '';
  const sigHeader = (event.headers['x-hub-signature-256'] ?? '').replace('sha256=', '');
  const expected = createHmac('sha256', process.env.GITHUB_WEBHOOK_SECRET).update(body).digest('hex');
  if (sigHeader.length !== expected.length ||
      !timingSafeEqual(Buffer.from(sigHeader, 'hex'), Buffer.from(expected, 'hex'))) {
    return { statusCode: 401, body: 'invalid signature' };
  }
  const eventType = event.headers['x-github-event'];
  const payload = JSON.parse(body);
  if (eventType === 'push') {
    await global.durable.startNew('index-repo', undefined, { repo: payload.repository.full_name, sha: payload.after });
  }
  return { statusCode: 200, body: 'accepted' };
}