DEMO: Realtime Settings
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1h 14m

Configuration is an important aspect of determining an application’s behavior. Settings files often include sensitive information like passwords and API keys. In this course, we will look at how to protect that sensitive information while the app is being developed and when it is in production.

Azure’s App Configuration Service allows you to manage access to settings data and we will see how to use it within a .Net application. We will look at using Azure Key Vault in conjunction with App Configuration Service, and how to access Azure Key Vault directly from your application and from apps running in a container within a Kubernetes cluster.

Next, we look at the idea of shifting left security testing within your development process, and how we can automate security testing as part of implementing a compliant development process. Much of this will involve using extensions from the Azure marketplace within your DevOps build pipeline.

This course contains numerous demonstrations from the Azure platform so that you can get a first-hand look at the topics we will be covering. If you have any feedback relating to this course, please contact us at

Learning Objectives

  • Learn about app configuration
  • Run and deploy apps with the Azure App Configuration service
  • Use Azure Key Vault to store secrets and certificates
  • Access Key Vault directly from your apps, including those running within a Kubernetes cluster
  • Create a compliant development process by integrating code analyzers, branch policies, quality gates, open-source library scanning, and automated penetration into a build pipeline

Intended Audience

  • Intermediate-level developers, DevOps engineers, and product managers
  • Anyone interested in learning how to implement secure app configurations and development pipelines


To get the most out of this course, you should have some pre-existing knowledge of software development and of using Microsoft Azure.


Having to restart the app to read updated configuration settings isn't ideal. There is a solution to this problem and that comes in the form of a special settings key called a sentinel key. The sentinel key is monitored by the app for changes in its configuration. Let's add the key to our settings with the name Sentinel an the value one with no label. In program.cs, I need to register the sentinel key to be monitored, and for the purpose of demonstration, I'll set the cache expiration to 10 seconds. This is saying when the sentinel key changes, refresh all the app settings.

By the way, there is nothing special about the word sentinel. You could call it anything you like, like settings have changed, but from what I've seen, calling it sentinel has become a bit of a convention. I'll add UseAppConfiguration to the configure method of startup.cs.

Next, I'll just add the current time to the home index page, so we can monitor what is going on. Right, I'll run the app and go back to the Azure portal and turn the orders features on and change the sentinel value. With that enabled, I'll just keep hitting refresh, and in a few seconds, we'll see the change. And there we go. The orders feature is now showing without having to restart the application.

About the Author
Learning Paths

Hallam is a software architect with over 20 years experience across a wide range of industries. He began his software career as a  Delphi/Interbase disciple but changed his allegiance to Microsoft with its deep and broad ecosystem. While Hallam has designed and crafted custom software utilizing web, mobile and desktop technologies, good quality reliable data is the key to a successful solution. The challenge of quickly turning data into useful information for digestion by humans and machines has led Hallam to specialize in database design and process automation. Showing customers how leverage new technology to change and improve their business processes is one of the key drivers keeping Hallam coming back to the keyboard.