AutoShutdownWorkflow.ps1

workflow AutoShutdownWorkflow
{
    #$VerbosePreference = "continue"
    
    # Automation Settings
    $pscreds = Get-AutomationPSCredential -Name "runbook-account"
    $subscriptionName = "[subscription name here]"
    $tagName = "autoShutdown"

    # Authenticate using WAAD credentials
    Add-AzureAccount -Credential $pscreds | Write-Verbose 

    # Set subscription context
    Select-AzureSubscription -SubscriptionName $subscriptionName | Write-Verbose

    Write-Output "Checking for resources with $tagName flag set..."

    # Get virtual machines within tagged resource groups
    $vms = Get-AzureResourceGroup -Tag @{ Name=$tagName; Value=$true } | Get-AzureResource -ResourceType "Microsoft.ClassicCompute/virtualMachines"

    # Shutdown all VMs tagged 
    $vms | ForEach-Object {
        Write-Output "Shutting down $($_.Name)..."
        # Gather resource details
        $resource = $_
        # Stop VM
        Get-AzureVM | ? { $_.Name -eq $resource.Name } | Stop-AzureVM -Force
    }
    
    Write-Output "Completed $tagName check"
}