Webhooks

Webhooks send notifications to external URLs when events happen in your system. Use them to integrate with other services, trigger automations, or sync data.

How webhooks work

• You register a webhook URL for specific triggers
• When the trigger occurs, the plugin sends a POST request to your URL
• Your server processes the data and takes action

Setting up webhooks

Add a webhook

• Go to Events > Settings > Webhooks
• Click Add Webhook
• Enter a name for reference
• Enter the delivery URL
• Select triggers to listen for
• Save

Webhook fields

Available triggers

Event triggers

Registration triggers

Attendee triggers

Capacity triggers

Webhook payload

Payload structure

{
  "id": "webhook_123456",
  "trigger": "registration.completed",
  "timestamp": "2025-01-15T10:30:00Z",
  "site_url": "https://yoursite.com",
  "data": {
    // Trigger-specific data
  }
}

Event created payload

{
  "trigger": "event.created",
  "data": {
    "event_id": 123,
    "title": "Tech Conference",
    "start_date": "2025-03-15",
    "start_time": "09:00",
    "end_date": "2025-03-15",
    "end_time": "17:00",
    "status": "scheduled",
    "type": "in-person",
    "venue": "Convention Center",
    "capacity": 500,
    "link": "https://yoursite.com/events/tech-conference/"
  }
}

Registration completed payload

{
  "trigger": "registration.completed",
  "data": {
    "attendee_id": 456,
    "event_id": 123,
    "event_name": "Tech Conference",
    "order_id": 789,
    "ticket_code": "EMWC-ABC123DEF",
    "first_name": "John",
    "last_name": "Doe",
    "email": "john@example.com",
    "custom_fields": {
      "company": "Acme Inc"
    }
  }
}

Attendee checked in payload

{
  "trigger": "attendee.checked_in",
  "data": {
    "attendee_id": 456,
    "event_id": 123,
    "event_name": "Tech Conference",
    "ticket_code": "EMWC-ABC123DEF",
    "name": "John Doe",
    "email": "john@example.com",
    "checked_in_at": "2025-03-15T09:15:00Z",
    "checked_in_by": "admin"
  }
}

Security

Signature verification

Each webhook includes a signature header for verification:

X-EMWC-Signature: sha256=abc123...

Verify in your code:

$payload = file_get_contents( 'php://input' );
$signature = $_SERVER['HTTP_X_EMWC_SIGNATURE'];

$expected = 'sha256=' . hash_hmac( 'sha256', $payload, $your_secret );

if ( hash_equals( $expected, $signature ) ) {
    // Valid webhook
}

Secret key

Set a secret key when creating the webhook. Keep it secure and use it to verify incoming requests.

HTTPS

Always use HTTPS URLs for webhook delivery to encrypt data in transit.

Delivery

Retry logic

If delivery fails:

• First retry: 1 minute after failure
• Second retry: 5 minutes after
• Third retry: 30 minutes after
• Final retry: 2 hours after

After 4 failures, the webhook is marked as failed.

Timeout

Requests timeout after 15 seconds. If your server needs more time, return a 200 status immediately and process asynchronously.

Response handling

Managing webhooks

Viewing webhooks

Go to Events > Settings > Webhooks to see:

• Webhook name and URL
• Triggers
• Status
• Delivery history

Webhook history

Click a webhook to see recent deliveries:

• Timestamp
• Trigger type
• Response code
• Payload sent
• Response received

Testing webhooks

• Edit a webhook
• Click Send Test
• A test payload is sent
• Check your endpoint received it

Pausing webhooks

To temporarily stop deliveries:

• Edit the webhook
• Change status to Paused
• Save

Triggers queue but do not deliver until reactivated.

Deleting webhooks

• Go to webhook list
• Hover over the webhook
• Click Delete
• Confirm deletion

Use cases

Slack notifications

Send event notifications to Slack:

• Create a Slack Incoming Webhook
• Add webhook with Slack URL
• Select registration.completed trigger
• New registrations post to Slack

Zapier integration

Connect to thousands of apps:

• Create a Zapier webhook trigger
• Add the Zapier URL as a webhook
• Build Zaps with event data

Custom CRM sync

Sync attendees to your CRM:

• Create endpoint in your CRM or middleware
• Add webhook for registration.completed
• Process payload to create CRM contacts

Analytics tracking

Send event data to analytics:

• Create endpoint for your analytics
• Add webhooks for desired triggers
• Log events for reporting

Email marketing

Add attendees to email lists:

• Set up endpoint connected to email service
• Use registration.completed trigger
• Add attendees to appropriate lists

Troubleshooting

Webhook not firing

• Check webhook is Active status
• Verify trigger is selected
• Confirm action should trigger (published event, completed order)

Delivery failures

• Check URL is accessible
• Verify HTTPS certificate is valid
• Check server is responding within 15 seconds
• Review error messages in delivery history

Wrong data received

• Verify trigger selection
• Check payload format
• Confirm endpoint is parsing JSON correctly

Signature validation failing

• Verify secret key matches
• Check payload is not modified
• Confirm hash algorithm (SHA-256)