Cannot Access Azure DevOps Variable for resourceName in Environment at Runtime

Question

I am setting up a deployment pipeline in Azure DevOps that targets a specific virtual machine (VM) resource in an environment. I want to dynamically pass the VM resource name using a variable defined in the Azure DevOps Variables section (the UI at the top right of the pipeline editor). However, I am unable to access this variable at runtime when using it in the resourceName field of the environment.

My Pipeline YAML

Here is the relevant section of my pipeline:

jobs:
- deployment: DeployToVM
  displayName: 'Deploy to VM'
  environment: 
    name: 'Production' # Static environment name
    resourceName: ${{ ResourceName }} # Variable for the VM resource name
    resourceType: VirtualMachine

  strategy:
    runOnce:
      deploy:
        steps:
        - script: echo "Deploying to $(ResourceName)"
          displayName: "Deployment Script"

What I Did

1. I added a pipeline variable in the Variables section of the Azure DevOps UI (top right):
   • Name: ResourceName
   • Value: MyResource (the name of the VM resource in the Production environment).
2. Referenced this variable in the YAML using resourceName: ${{ ResourceName }}.

The Problem

When I run the pipeline, I get the following error:

Resource '' does not exist in environment 'Production'.

It seems like the resourceName field cannot resolve the value of the variable ResourceName. However, I can successfully echo the value of $(ResourceName) in the steps section, so the variable itself is accessible in other contexts.

What I Tried

• Tried using both $(ResourceName) and ${{ ResourceName }} in the resourceName field.
• Verified that the Production environment exists and contains the VM resource MyResource.
• Tested with hardcoding the value (resourceName: 'MyResource'), which works fine.

My Questions

1. Why can’t I use a variable for the resourceName field in the environment definition?
2. Is there a way to dynamically reference a VM resource in an environment using a variable defined in the Azure DevOps Variables section?

Additional Information

• I am using Azure DevOps YAML pipelines with a multi-stage setup.
• The VM (MyResource) is correctly registered in the Production environment.

Any help or insights would be appreciated!

Answer 1

Using pipeline variables

You're using the wrong syntax to reference variables.

Instead of:

${{ ResourceName }}

Use template expressions (compile time):

${{ variables.ResourceName }}

Or use macro syntax (runtime):

$(ResourceName)

Using pipeline parameters

If you need user input when queuing a new pipeline I'd recommend using a pipeline parameter instead of a variable.

Parameters are a better choice because they are strongly-typed, will be compiled and are immediately visible when you queue a new build. The only good reason IMO to use UI variables is if you need to set secret variables.

As an alternative to variables, use a pipeline parameter:

# my-pipeline.yaml

parameters:
  - name: ResourceName
    type: String
    displayName: Name of the virtual machine

jobs:
- deployment: DeployToVM
  displayName: 'Deploy to VM'
  environment: 
    name: 'Production' # Static environment name
    resourceName: ${{ parameters.ResourceName }} # <------ use pipeline parameter
    resourceType: VirtualMachine
  # ...