Azure Event Grid is a fully managed, intelligent event-routing service. With Azure Event Grid, enterprise applications can leverage an event-driven programming model to build reactive interfaces that can be used to connect external or internal applications. Using Azure Event Grid as a middleware messaging layer for application and interface integration helps organizations to optimize the performance of their software resources with a notification push design pattern, rather than a data pull operation model. Azure Event Grid works with a publish-subscribe mechanism, where you can have one or more event publishers and with each event, there can be one or more subscribers consuming the events.

In the following example, Logic Apps acts as a subscriber to the event published to Azure Event Grid. Events are routed to a Logic Apps endpoint in real time, and once an event is posted to the Logic App endpoint, a Logic Apps workflow sends an auto-triggered email using a Logic Apps-managed API connector for Office 365:

Azure Event Grid is the perfect match for Logic Apps and Azure Functions, and you can leverage events emitted from your environment or external resources to react in real time, instead of consuming resources through a polling-based mechanism. Various blogs and articles have been written on how to use the capabilities of Azure Event Grid, along with other connecting Azure resources such as Data Factory, blob storage, Service Bus, and external services.

This book has dedicated a chapter to the use of Azure Event Grid within enterprise applications, and how you can connect Event Grid services to an application of your choice and reap the benefits of the event-based messaging pattern.

We've now covered the basics of all the services that constitute Azure Integration Services. In the coming chapters, we will discuss each of these services separately, looking at their various architecture design patterns along with the code that can be implemented within your enterprise integration framework.