Packager Building Image for Windows - using azure-arm builder

packer.json

{
  "variables": {
    "client_id": "{{env `AZURE_CLIENT_ID`}}",
    "client_secret": "{{env `AZURE_CLIENT_SECRET`}}",
    "subscription_id": "{{env `AZURE_SUBSCRIPTION_ID`}}",
    "tenant_id": "{{env `AZURE_TENANT_ID`}}",
    "spn_object_id": "{{env `AZURE_SPN_OBJECT_ID`}}",
    "resource_group": "{{env `AZURE_BUILD_RESOURCE_GROUP`}}",
    "resource_location": "{{env `AZURE_BUILD_LOCATION`}}",
    "storage_account": "{{env `AZURE_BUILD_STORAGE_ACCOUNT`}}",
    "vm_size": "{{env `AZURE_DEFAULT_VM_SIZE`}}",
    "image_os_sku": "2016-Datacenter-Server-Core"
  },
  "builders": [{
    "type": "azure-arm",

    "client_id": "{{user `client_id`}}",
    "client_secret": "{{user `client_secret`}}",
    "subscription_id": "{{user `subscription_id`}}",
    "tenant_id": "{{user `tenant_id`}}",
    "object_id": "{{user `spn_object_id`}}",

    "managed_image_name": "{{user `image_os_sku`}}--{{isotime \"2006.01.02-1504\"}}",
    "managed_image_resource_group_name": "{{user `resource_group`}}",
    "managed_image_storage_account_type": "Premium_LRS",

    "os_type": "Windows",
    "image_publisher": "MicrosoftWindowsServer",
    "image_offer": "WindowsServer",
    "image_sku": "{{user `image_os_sku`}}",

    "communicator": "winrm",
    "winrm_use_ssl": "true",
    "winrm_insecure": "true",
    "winrm_timeout": "5m",
    "winrm_username": "packer",

    "location": "{{user `resource_location`}}",
    "vm_size": "{{user `vm_size`}}"
  }],
  "provisioners": [
    {
      "type": "windows-shell",
      "inline": [
        "powershell.exe -ExecutionPolicy bypass -windowstyle hidden -Command $PSVersionTable",
        "systeminfo"
      ]
    },
    {
      "type": "powershell",
      "inline": [
        "(gcim win32_service | ? { $_.name -match 'WindowsAzureGuestAgent' }).PathName",
        "get-service WindowsAzureGuestAgent | ft -autosize"
      ]
    },
    {
      "type": "powershell",
      "inline": [
        "if( Test-Path $Env:SystemRoot\\windows\\system32\\Sysprep\\unattend.xml ){ rm $Env:SystemRoot\\windows\\system32\\Sysprep\\unattend.xml -Force}",
        "& $Env:SystemRoot\\System32\\Sysprep\\Sysprep.exe /oobe /generalize /quit /quiet",
        "while($true) { $imageState = Get-ItemProperty HKLM:\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Setup\\State | Select ImageState; if($imageState.ImageState -ne 'IMAGE_STATE_GENERALIZE_RESEAL_TO_OOBE') { Write-Output $imageState.ImageState; Start-Sleep -s 10  } else { break } }"
      ]
    }
  ]
}