At the recently concluded Build Conference, the Microsoft Azure team announced the preview of Functions, an app service that allows you to execute code on demand. Azure Functions is event-driven and allows serverless execution of code triggered as a result of an event or a coordinated set of events. It allows you to extend the application platform capabilities of Azure without having to worry about compute or storage. The events don?t have to only be occurring in Azure, but in virtually any environment including on-premise systems. You can also make Functions connected to be part of a data processing or messaging pipeline, thereby executing code asynchronously as part of a workflow. In addition, Azure Functions Apps can scale on demand, allowing you to pay for only what you use.

Azure Functions offers support for a myriad of languages, such as PHP, C# and most of the scripting languages (Bash and PowerShell, for example). You can also upload and trigger pre-compiled code and support dependencies using NuGet and NPM. Azure Functions can also run in a secure setting by making them part of an app service environment configured for a private network. Out of the box, it supports OAuth providers such as Azure Active Directory, Facebook, Google, etc.

To create a Functions app login to your Azure portal and search for Functions in the Marketplace search bar.

Select the Function App service, provide a name, select a resource group and create the app.

Once you create a Function app, it also creates an AppInsights monitoring app that attaches to monitor the health of the Functions app. After the Function app is deployed, you can navigate to the Function App console from the dashboard. The console has two windows. The Code window (an editor with a code highlighter) is where you can put your script and then you can verify the outcome under the Logs window.

You can then make the Function integrate with an event driven workflow as illustrated in the figure below:

You can configure an input and an output for the trigger in the Integrate tab. In this example, a storage queue is set as the default trigger but you can set it to be a Schedule, a Webhook, or Push Notifications amongst others.

There are also a bunch of pre-defined templates you can use to start creating your function from scratch.

Additionally, there are several advanced settings available for you to configure, for example setting up authentication, authorization, integrating with a source control for continuous integration, enabling CORS and providing API definitions to allow clients to easily call them.

In a world heavily dominated by the likes of Amazon, Google, and IBM, it is a good move for Microsoft to release Azure Functions, providing more options for developers and enterprises to choose and extend their PaaS implementation.