How to use Key Vault reference locally in asp.net (framework) application

Question

Key Vault reference works locally for DotNet Core apps (Functions, ASP.NET Core). But can we use Key Vault reference locally in ASP.NET (Framework) applications.

E.g.

In framework app, we read app setting values as follows:

using System.Configuration;

var mySecretValue = ConfigurationManager.AppSettings["myKey"];

In my web.config file the value of this key is a key vault reference:

<appSettings>

<add key="myKey" value="@Microsoft.KeyVault(SecretUri=https://myvault.vault.azure.net/secrets/myKey))"/>

</appSettings>

The above works fine when deployed on Azure App Service. I deploy the App Settings under App Service --> Configuration --> AppSettings. mySecretValue variables gets the value of the secret stored in KV.

But when this is run locally, it just gets the literal string stored in web.config file:

E.g.

Value of mySecretValue is @Microsoft.KeyVault(SecretUri=https://myvault.vault.azure.net/secrets/myKey))

It does not resolve the Key Vault reference.

Please note that I run Visual Studio as "Admin" and the Sign-in account in VS has permissions to the respective KV.

Please note that I cannot use Environment.GetEnvironmentVariable() in this case because it is ASP.NET (Framework) app.

Any pointers are appreciated.

Answer 1

Hi @Bhavya Shah,

Have you tried adding Key Vault to your web application using Visual Studio Connected Services.

You can follow the documentation steps below and follow this tutorial and your Key Vault permissions will be set up to work with your own Azure subscription.

Add Key Vault to your web application by using Visual Studio Connected Services

You can also refer to the following documents:

How to Override Web.config values with Azure KeyVault in .NET Framework 4.7.1

On-prem ASP.NET Framework web app with Azure Key Vault

Please note that I cannot use Environment.GetEnvironmentVariable() in this case because it is ASP.NET (Framework) app.

By the way, the Environment.GetEnvironmentVariable method is also available in the .NET Framework.

https://learn.microsoft.com/en-us/dotnet/api/system.environment.getenvironmentvariable?view=netframework-4.8

Best regards,
Lan Huang

---

If the answer is the right solution, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.