Using templates to better manage Puppet code

While inline PowerShell is usable as an exec resource in your manifest, such code can be difficult to read and maintain, especially when it comes to handling escaping rules.

For executing multi-line scripts, use Puppet templates instead. The following example shows how you can use a template to organize the code for disabling Windows drive indexing.

$drive = 'C:'

exec { 'disable-c-indexing':
  command   => template('Disable-Indexing.ps1.erb'),
  provider  => powershell,
  unless    => "if ((Get-WmiObject -Class Win32_Volume -Filter 'DriveLetter=\"${drive}\"').IndexingEnabled) { exit 1 }",

The PowerShell code for Disable-Indexing.ps1.erb becomes:

function Disable-Indexing($Drive)
  $drive = Get-WmiObject -Class Win32_Volume -Filter "DriveLetter='$Letter'"
  if ($drive.IndexingEnabled -ne $True) { return }
  $drive | Set-WmiInstance -Arguments @{IndexingEnabled=$False} | Out-Null

Disable-Indexing -Drive '<%= @driveLetter %>'