A webhook is a mechanism for conveying to some external system a change that took place in NetBox. For example, you may want to notify a monitoring system whenever the status of a device is updated in NetBox. This can be done by creating a webhook for the device model in NetBox and identifying the webhook receiver. When NetBox detects a change to a device, an HTTP request containing the details of the change and who made it be sent to the specified receiver. Webhooks are managed under Logging > Webhooks.
Webhooks support the inclusion of user-submitted code to generate URL, custom headers and payloads, which may pose security risks under certain conditions. Only grant permission to create or modify webhooks to trusted users.
* **URL** - The fully-qualified URL of the request to be sent. This may specify a destination port number if needed. Jinja2 templating is supported for this field.
* **HTTP content type** - The value of the request's `Content-Type` header. (Defaults to `application/json`)
* **Additional headers** - Any additional headers to include with the request (optional). Add one header per line in the format `Name: Value`. Jinja2 templating is supported for this field (see below).
* **Body template** - The content of the request being sent (optional). Jinja2 templating is supported for this field (see below). If blank, NetBox will populate the request body with a raw dump of the webhook context. (If the HTTP cotent type is set to `application/json`, this will be formatted as a JSON object.)
* **Secret** - A secret string used to prove authenticity of the request (optional). This will append a `X-Hook-Signature` header to the request, consisting of a HMAC (SHA-512) hex digest of the request body using the secret as the key.
[Jinja2 templating](https://jinja.palletsprojects.com/) is supported for the `URL`, `additional_headers` and `body_template` fields. This enables the user to convey object data in the request headers as well as to craft a customized request body. Request content can be crafted to enable the direct interaction with external systems by ensuring the outgoing message is in a format the receiver expects and understands.
For example, you might create a NetBox webhook to [trigger a Slack message](https://api.slack.com/messaging/webhooks) any time an IP address is created. You can accomplish this using the following configuration:
* Object type: IPAM > IP address
* HTTP method: `POST`
* URL: Slack incoming webhook URL
* HTTP content type: `application/json`
* Body template: `{"text": "IP address {{ data['address'] }} was created by {{ username }}!"}`
### Available Context
The following data is available as context for Jinja2 templates:
*`event` - The type of event which triggered the webhook: created, updated, or deleted.
*`model` - The NetBox model which triggered the change.
*`timestamp` - The time at which the event occurred (in [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601) format).
*`username` - The name of the user account associated with the change.
*`request_id` - The unique request ID. This may be used to correlate multiple changes associated with a single request.
*`data` - A detailed representation of the object in its current state. This is typically equivalent to the model's representation in NetBox's REST API.
*`snapshots` - Minimal "snapshots" of the object state both before and after the change was made; provided as a dictionary with keys named `prechange` and `postchange`. These are not as extensive as the fully serialized representation, but contain enough information to convey what has changed.
If no body template is specified, the request body will be populated with a JSON object containing the context data. For example, a newly created site might appear as follows:
