Event Grid is a managed event routing platform which enables you to react in real time to changes happening in Azure resources or your own application. Today, in order to discover a state change in a resource like a new database entry or a VM creation, we usually perform either continuous or scheduled polling. That means that you are continuously consuming CPU resources and also the network resources.

However, using Event Grid, applications can now send events when state changes occur by using push semantics just like push notifications. Those are only engaged once actionable events are sent. Anyone interested on acting on those events can subscribe and be notified without polling which in turn reduces your required compute resources.

Event Grid handles built-in Azure events from Azure Services, as well as custom events from your apps and publishes them in real time. It can dynamically scale to handle millions of events every second. It also offers the four nine SLA i.e. 99.99% SLA. As events are received, Event Grid facilitates the triggering of programmatic actions via event handlers such as Azure Automation, Event Hubs, Azure functions, Logic Apps or Custom Web Hooks.

Because everything is based on HTTP, Event Grid can integrate with virtually any service or app. This becomes powerful in:

• Simplifying ops and security automation through easier policy enforcement
• In expanding serverless compute scenarios with no eventing sources
• In enabling better communication and integration between your event-based services and apps.

In the Azure portal, we can write a script for Azure Automation so that any time a specific event is fired, it will trigger a specific action.

Azure Event Grid has pay-per-event pricing model. So, you only pay for what you use. And to help you get started quickly, the first 1,00,000 are operations per month are free and then after that, it is 60 cents per million operations. Along with that, you can also take advantage of Azure’s management and runtime SDKs to publish and subscribe to events.