So, what is Azure App Service? I guess it could be simply and crudely described as a cloud-based web hosting service, but if you've had any experience with hosting a web site at a traditional Internet service provider, you'll soon realize it's so much more. In a traditional hosting scenario that is analogous to hosting on a virtual machine, you get the machine loaded with a web server, and that is pretty much it. You need to figure out how to get your code onto the server, whether that is by FTP or file copy, and get it served up correctly. Any logging over and above web server logs, you will need to implement yourself. You will have to set up any associated database servers and their connections. If your web app receives more traffic than expected and you need to upgrade the server, then you will have to redeploy to a new environment with more capacity. This process is a headache at the very least and can result in unwanted downtime.

Azure App Service's difference is in the name. It's all about serving your app, freeing you from thinking about all the associated infrastructure and support services.

Apart from just hosting a web application or API, App Service allows an app to connect and make use of a wide range of Azure services and resources. You can secure a web application with third party identity authentication providers Application insights and diagnostics provide an abundance of metrics about your app's usage and performance. Automated features like autoscaling based usage metrics make your app more responsive to changing workloads, and automatic snapshot backups provide a rollback safeguard. You can use a custom domain with App service and secure your app service with SSL certificates. Virtual networks are another way you can securely access an app or give an app access to on-premise resources. You can set up alerts to warn and inform of critical resource use situations and then scale up or down appropriately. You can carry out background support tasks with scheduled jobs and provide users with a more interactive experience using push notifications. App Service provides diagnostic features to help you ensure your app is performing as expected. For app development, there is integration with popular code repository providers.

I've just touched on a lot of functionality and features, and that's not all of them. As this is an introduction course, and not everyone has the same background and experience, I'll try to keep general. If you aren't from a development discipline, please bear with me as I will start with deploying web applications but will move on to configuration and management.

Supported frameworks and languages

On that note, which framework and programming language you use to build your web app have vital implications on production environment configuration. Interpreted or script languages such as PHP, Python, JavaScript, and Ruby need different web server setups than compiled libraries like .Net. While .Net Core apps can run on Linux, standard .Net apps need Windows. Azure App Service supports a wide range of languages and frameworks on both Windows and Linux operating systems, as well as Docker containers.