WebHooks are a way of connecting internet / cloud services together. They allow websites to communicate with each other via HTTP callbacks. Services can subscribe (via HTTP) to receive notifications from publishers about a specific event. Publishers, manage these subscriptions and then on each event push notifcations via an HTTP Post to each receiver, at an endpoint defined during subscription.
Microsoft have recently released a WebHook framework for ASP.NET that gives you a pattern for:
- Handling subscriptions from interested subscribers
- Sending subscriptions to publishers
- Sending published messages to subscribers
- Handling publisher messages from subscribed services (via Receivers)
Webhooks in EPiServer
What would an EPiServer implementation / usage of WebHooks look like?
- Publish content events to subscribers (system to system integration)
- Publish Form data inputs to external systems
- Publish / Subscribe to Catalog events and changes from integrated commerce systems (Stock control and pricing)
- Subscribe to events from external systems (Payments)
- Subscribe to external content events – Instagram / social
As part of a presentation I put together a simple solution demonstrating an EPiServer site with an Instagram receiver that provided a solution to the below user story.
“As a content editor, I want images that are uploaded on a social channel (Instagram) and tagged with ‘ascend15’ to be available in my content management system so I can use them on my awesome website”
The solution contained the following elements:
- A receiver accepting notifications from Instagram when a image with a tag of ‘ascend15’ was added (using the ASP.NET WebHook framework)
- A Dynamic Data Store implementation to store the number of notifications received
- A scheduled job: to request, download and import images into EPiServer as MediaData / IContent items
The solution and even the scenario was a little contrived, so I’m not going to show the code (though it you really want it just drop me a line). It did however work on the day, which when you’re trying a tech demo that relies on the cloud and external services and also your own code; is always nice