Interested in using Webhooks?
Webhooks in Spotler SendPro are an add-on. To explore the possibilities, please contact your account manager.
Webhooks in Spotler SendPro allow you to receive real-time updates about specific message events in your own system. This is ideal if you are already using Event Flows in SendPro, want to link multiple systems and products together or if you have build your own front end on top of our API. Event Flows and Webhooks work differently, so you can pick which method works best for you.
In this article you will learn more about:
Webhooks overview
The Webhooks page displays a list of all configured webhooks, including their Description, Webhook URL, and Status. From this overview, you can create a new webhook or manage existing ones through the three-dot menu (Edit, Enable/Disable webhook, delete).
Create or edit a Webhook
When you click in Create Webhook, you start setting up a new webhook. Editing a webhook will send you to the same page, this page is already filled in with data from the already set up webhook. Here you will find the following fields:
General settings
- Description: Name of the webhook
- Webhook URL: Endpoint that receives events
- Add message tags from the original message: Include original message tags, if available
Filters (optional)
- Filter sources: Filter from selected sources (default: all sources included)
- Filter event types: Filter on types of events (default: all events included)
Webhook filters
When creating a new webhook, all available sources and event types are enabled by default. Although the filter fields appear empty, this does not mean that nothing is selected. If you leave the filter unchanged, the webhook will deliver all events from all sources.
To limit the scope of the webhook, you can manually select specific sources and/or event types:
- Open the webhook configuration screen.
- In the Sources section, select the sources you want to include.
- In the Event types section, select the event types you want to include.
Once selected, only the chosen sources and event types will be delivered to the webhook.
Headers
You can add custom headers (Header name + Header value) to support Header Authentication or to easily recognise the webhook.
Advanced settings
- API version: Defaults to latest available version
- Max batch size: Maximum number of events per call
- Max concurrency: Number of parallel connections allowed
Limits
Max concurrency and Max batch size define how fast and how many events are sent. These are advanced parameters typically set by Spotler during setup or support. If needed, contact Spotler Support to discuss adjusting these limits.
Webhook status
- Toggle to enable or disable the webhook
Webhook details page
This page provides a read-only summary of the webhook settings, including:
- Description
- Webhook URL
- API Version
- Enabled (yes/no)
- Add message tags (yes/no)
- Max batch size
- Max concurrency
- Any custom request headers
From here you can find three types of actions: Edit, Back, or Delete. Once you delete a webhook, the webhook will be permanently deleted.
Error handling
When a webhook endpoint is temporarily unreachable, SendPro automatically schedules retries. If the failures persist, the webhook is gradually moved to a slower retry group to reduce system load. After 24 hours without a successful delivery, the webhook is disabled.
Webhook owners are notified when a webhook is moved to a slower group or disabled due to repeated failures. Notifications appear in the top-right corner of the software, under the notification bell icon, just like other system messages. If configured, these alerts can also be sent via email.
Webhook notifications contain detailed technical context to help identify what happened. A typical message includes:
- Webhook name – the specific webhook that triggered the alert
- Group transition – the retry group the webhook was moved from and to
-
Error code – the HTTP status received from the endpoint, e.g.
404 - Number of events – how many events were part of the failed attempt
- Call duration – how long the system waited before marking the attempt as failed
- Partition – internal process identifier for support purposes
One webhook call may include multiple events. These are bundled for delivery and retry. It is not possible to view or extract individual events from the notification.
Retry behavior is handled through a system of progressive retry groups. These groups determine how often and how long the system waits before the next delivery attempt:
- Direct – initial attempt (no delay)
- 5 minutes – short delay, 2 retries
- 30 minutes – medium delay, 2 retries
- 1 hour – extended delay, 3 retries per hour
- Sweeper – for persistent failures, with continued retrying
Movement between these groups is automatic and based on failure patterns. If the receiving endpoint becomes available again, the webhook is automatically promoted back to a faster group.
Always contact support in case of webhook issues
If your webhook is experiencing issues, you can contact support for help. Risks from a failing endpoint are your own responsibility.