@Anonymous , We have been looking for your confirmation on the scenario/requirement you're attempting to accomplish.
As Ryan mentioned, you can implement basic auth.
If you're trying to understand/implement the ability for users to access App Service WebApp only upon authentication, it is possible. Azure App Service does provide built-in authentication and authorization support, so you can sign in users and access data by writing minimal or no code in your web app.
However, On Container/App Service - The authentication and authorization module runs in a separate container, isolated from your application code. Using what's known as the Ambassador pattern, it interacts with the incoming traffic to perform similar functionality as on Windows. Because it does not run in-process, no direct integration with specific language frameworks is possible; however, the relevant information that your app needs is passed through using request headers
as explained in this document.
Hope this helps! Kindly let us know we will be happy to assist you further.
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