Often when creating an Azure DevOps continuous integration/deployment pipeline there’s a need to store and use app secrets, such as client keys. While you can store secrets within Azure DevOps variable groups, an alternative approach is to use Azure Key Vault instead.
Want to secure your Azure DevOps application secrets in Key Vault? Find out how in our short e-book guide on Amazon
By using Azure Key Vault you get the same enhanced data protection that your other cloud apps can enjoy including activation and expiration dates, and the DevOps integration allows for the centralised management of keys used across apps or pipelines. Keep in mind if you decide to use key vault, you will be charged according to the Azure Key Vault pricing for storing your secrets.
Setting up Key Vault access in Azure DevOps
Getting started is easy. Open Azure DevOps, and navigate to the project you wish to integrate with. Open the Pipelines section, and then go to Library.
If you already have secrets and values stored in an existing library, the easiest way to integrate with key vault is to create a separate variable group. If you don’t, you’ll get a message warning you that when you enable key vault in your existing group, it’ll blow away all your existing variables saved within the group. This is because you can’t use key vault variables side by side with Dev Ops variables within one group.
Open the new variable group, and you should see a toggle to link secrets from an Azure key vault as variables. Turn that on, and you’ll see the option to set the Azure subscription to be used, and a field to specify a key vault name.
You’ll need to ensure that you’ve previously setup a connection to your Azure subscription within Azure DevOps, and added an Azure Resource Manager service connection using an Azure Service Principal to the resource group where your key vault is located. If you haven’t, the management links next to each field will help you to setup these connections.
Once connected, pointing DevOps to your key vault is as easy as choosing the correct subscription from the drop down list and then selecting your key vault by name in the second drop down. If your service principal doesn’t have get and list secret management permissions, you’ll be prompted to automatically authorise it or manually do so in the Azure Portal.
If successfully connected, you’ll be able to then see a list of secrets from your key vault by clicking the add button. Choose the secrets you want to make available to your pipeline and click OK.
Add your new variable group to your pipeline, and that’s all there is to adding key vault secrets to an Azure DevOps pipeline.