Seshn + Twilio

1npm install twilio

1import twilio from 'twilio';
2import { createHmac } from 'crypto';
3
4const client = twilio(
5  process.env.TWILIO_ACCOUNT_SID,
6  process.env.TWILIO_AUTH_TOKEN
7);
8const FROM_NUMBER = process.env.TWILIO_PHONE_NUMBER!;
9const WEBHOOK_SECRET = process.env.SESHN_WEBHOOK_SECRET!;
10
11export async function POST(req: Request) {
12  const body = await req.text();
13  const signature = req.headers.get('x-webhook-signature');
14
15  const expected = 'sha256=' +
16    createHmac('sha256', WEBHOOK_SECRET).update(body).digest('hex');
17
18  if (signature !== expected) {
19    return new Response('Invalid signature', { status: 401 });
20  }
21
22  const event = req.headers.get('x-webhook-event');
23  const payload = JSON.parse(body);
24
25  // Only send SMS if the contact has a phone number
26  if (!payload.contact?.phone) {
27    return new Response('No phone number', { status: 200 });
28  }
29
30  let message: string | null = null;
31
32  switch (event) {
33    case 'booking.created':
34      const date = new Date(payload.slot.startTime);
35      message = `Booking confirmed: ${payload.service.name} on ${date.toLocaleDateString()} at ${date.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' })}. ${payload.seats} seat(s).`;
36      break;
37
38    case 'booking.cancelled':
39      message = `Your booking for ${payload.service.name} has been cancelled.`;
40      break;
41
42    case 'booking.hold_expired':
43      message = `Your held spot for ${payload.service.name} has expired. Book again at ${payload.bookingUrl ?? 'our website'}.`;
44      break;
45
46    case 'waitlist.promoted':
47      message = `A spot opened up! You've been booked for ${payload.service.name}.`;
48      break;
49  }
50
51  if (message) {
52    await client.messages.create({
53      body: message,
54      from: FROM_NUMBER,
55      to: payload.contact.phone,
56    });
57  }
58
59  return new Response('OK', { status: 200 });
60}

1curl -X POST https://api.seshn.net/v1/webhooks \
2  -H "Authorization: Bearer sk_live_..." \
3  -H "Content-Type: application/json" \
4  -d '{
5    "url": "https://yourdomain.com/api/webhooks/seshn",
6    "events": [
7      "booking.created",
8      "booking.cancelled",
9      "booking.hold_expired",
10      "waitlist.promoted"
11    ]
12  }'