How do I trigger push notifications from a webhook or event?

To trigger push notifications from a webhook or event, you generally need this flow:

1. An event happens
   Example: a payment succeeds, a new message arrives, a ticket is updated.

2. A webhook endpoint or event handler receives it
   Your backend exposes an endpoint like POST /webhooks/... or listens to events from a queue / pub-sub system.

3. Your backend decides who should be notified
   Look up the user(s), device tokens, topics, or segments.

4. Your backend calls a push notification service
   Common options:

   • Firebase Cloud Messaging (FCM)
   • Apple Push Notification service (APNs) directly for iOS
   • OneSignal
   • Expo Notifications
   • AWS SNS / Pinpoint
   • Pusher Beams, etc.

5. The service delivers the notification to the device(s)

Typical architecture

Webhook/Event → Your server → Push provider API → Mobile device

You usually do not send push notifications directly from the webhook provider. Instead, your webhook triggers your own backend, and your backend sends the push.

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Example with a webhook

1. Receive webhook

app.post('/webhook', async (req, res) => {
  const event = req.body;

  if (event.type === 'order.shipped') {
    // find user/device tokens
    await sendPushToUser(event.userId, {
      title: 'Your order shipped!',
      body: `Tracking: ${event.trackingNumber}`,
    });
  }

  res.sendStatus(200);
});

2. Send push via FCM

async function sendPushToUser(userId, notification) {
  const tokens = await getDeviceTokensForUser(userId);

  await fetch('https://fcm.googleapis.com/fcm/send', {
    method: 'POST',
    headers: {
      'Authorization': `key=${process.env.FCM_SERVER_KEY}`,
      'Content-Type': 'application/json',
    },
    body: JSON.stringify({
      registration_ids: tokens,
      notification,
    }),
  });
}

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Best practices

• Verify webhook signatures so only trusted events trigger pushes.
• Make webhook handling fast; queue the notification job if possible.
• Deduplicate events to avoid duplicate notifications.
• Store device tokens per user and clean up invalid ones.
• Use background jobs for retries and reliability.
• Respect user preferences and notification settings.

---

Recommended pattern for reliability

For production, do this:

Webhook handler

• validates event
• stores event in DB / queue
• returns 200 OK quickly

Worker

• processes event
• determines recipients
• sends push
• retries on failure

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If you want, I can show you a complete example for:

• Node.js + Firebase Cloud Messaging
• Python + FCM
• OneSignal
• iOS/Android app setup
• or a webhook-to-push architecture diagram