Building SharePoint Webhook Services with Serverless Architecture

Before looking out at the implementation of webhook models in SharePoint, here let us look at how Serverless web hooks concept can be feasible.

What is Serverless architecture? It allows us to build the required services, without the need of servers. Some Azure services like Azure functions helps building such Serverless models.

The components like webhook service, storage queues, web jobs and SQL database are hosted on Azure. The following picture depicts the Serverless webhooks process, with the help of Serverless components. The components present on the Azure box, depicts serverless architecture model.

Serverless Architecture for SharePoint Webhook Services

Processing Events from SharePoint Webhook Services

Let us theoretically look how the event changes are retrieved from the storage queues, processed and stored on to the logs like SharePoint history lists.

In the previous post, you have seen how to subscribe to the event changes on SharePoint online and how the events are stored on the storage queue. Here, you could see how the events stored can be processed.

Process Data from the Queue - Web Jobs

If we closely look in the previous post, SharePoint service has sent few details to the notification service when the event change had happened on SharePoint. In the details, you can only see what has changed at high level. That is, which list has changes. It doesn’t define, what are the changes.

Event Change Details

Working with SharePoint Events using Webhooks

Introduction

In this post, let us look in detail on webhooks functionality. At a high level, there are two independent steps to work with Webhooks.

• Subscribing to the SharePoint events (remote events)
• Processing Events.

Note: In the recent SharePoint Saturday Event at Chennai, I have explored on using Serverless Webhooks. For the benefits of larger audience, I am writing down as a technical post in detail with explanations.

Subscribing to the SharePoint Events

SharePoint by default provides the subscription mechanism for event changes. For now, only item level changes can be tracked, that on SharePoint online platform.

Introduction to SharePoint Webhooks

What is Webhook?

Web hook is a general concept for http based events, which will provide remote event mechanisms.

Say for example, you have a built a custom application separately which has some specific product related content. Whenever there is a data change on the product repository, your data on the custom application should also be updated. For this scenario, will you be keep on checking the product repository for the changes? The answer should be No. Instead of your application keep on poll the product for changes, product should notify or push the changes to your application.

What is SharePoint Webhook?

Previously for working with event based processes, we were using the server side event receivers and remote events receivers. Such processes can be replaced with the webhooks.