Besides access tokens, Azure Event Grid also checks whether or not an endpoint is valid and secure. This validation will not happen for the following handler types:
- Azure Logic Apps
- Azure Automation
- Azure Functions when EventGridTrigger is used
The rest of the endpoints (and especially those triggered by an HTTP request) have to be validated to be used. Here is how that kind of validation is processed:
- Firstly, SubscriptionValidationEvent is sent to an endpoint containing multiple fields, such as topic, validation code, and others. Additionally, a special aeg-event-type: SubscriptionValidation header is sent.
- Secondly, Event Grid expects a success response containing a validation code that was sent in the request. ...
