clerk-webhooks

Clerk Webhooks

When to Use This Skill

• Setting up Clerk webhook handlers
• Debugging signature verification failures
• Understanding Clerk event types and payloads
• Handling user, session, or organization events

Essential Code (USE THIS)

Express Webhook Handler

Clerk uses the Standard Webhooks protocol (Clerk sends svix-* headers; same format). Use the standardwebhooks npm package:

const express = require('express');
const { Webhook } = require('standardwebhooks');

const app = express();

// CRITICAL: Use express.raw() for webhook endpoint - verification needs raw body
app.post('/webhooks/clerk',
  express.raw({ type: 'application/json' }),
  async (req, res) => {
    const secret = process.env.CLERK_WEBHOOK_SECRET || process.env.CLERK_WEBHOOK_SIGNING_SECRET;
    if (!secret || !secret.startsWith('whsec_')) {
      return res.status(500).json({ error: 'Server configuration error' });
    }
    const svixId = req.headers['svix-id'];
    const svixTimestamp = req.headers['svix-timestamp'];
    const svixSignature = req.headers['svix-signature'];
    if (!svixId || !svixTimestamp || !svixSignature) {
      return res.status(400).json({ error: 'Missing required webhook headers' });
    }
    // standardwebhooks expects webhook-* header names; Clerk sends svix-* (same protocol)
    const headers = {
      'webhook-id': svixId,
      'webhook-timestamp': svixTimestamp,
      'webhook-signature': svixSignature
    };
    try {
      const wh = new Webhook(secret);
      const event = wh.verify(req.body, headers);
      if (!event) return res.status(400).json({ error: 'Invalid payload' });
      switch (event.type) {
        case 'user.created': console.log('User created:', event.data.id); break;
        case 'user.updated': console.log('User updated:', event.data.id); break;
        case 'session.created': console.log('Session created:', event.data.user_id); break;
        case 'organization.created': console.log('Organization created:', event.data.id); break;
        default: console.log('Unhandled:', event.type);
      }
      res.status(200).json({ success: true });
    } catch (err) {
      res.status(400).json({ error: err.name === 'WebhookVerificationError' ? err.message : 'Webhook verification failed' });
    }
  }
);