Powershell parallel foreach reference demo code

PowershellParallelForeach.ps1

# some function we want available in our parallel runspace
function Get-DummyItem {
	[CmdletBinding()]
	Param (
		[Parameter(Mandatory)]
		[string]$Name
	)
	$myIp = Invoke-WebRequest -Method Get -Uri 'https://api.my-ip.io/ip'
	"[$Name] was processed by [$myIp]"
}

# ...

	#some sample data to iterate over
	$testData = 1..100 | %{[PSCustomObject]@{ID=$_;Name="Someone Number $_"}}
	
	# a variable outside our parallel runspace
	$appendString = 'Hello'
	
	# get the definition of any functions created in current scope so we can make them available in our parallel thread's runspace
	$getDummyItemParallel = ${function:Get-DummyItem}.ToString()
	
	# Do the loop... here I'm assigining the output to a variable so that later we can amend the order of the output from all threads before returning
	[pscustomobject[]]$output = $testData | ForEach-Object -ThrottleLimit 15 -Parallel {
		
		# bug work around https://github.com/PowerShell/PowerShell/issues/13816
		# for any preference variables ensure they're the same in our runspace as the caller's (note: this isn't a complete list; e.g. things like ShouldProcess aren't covered - see the github issue for a better example)
			$DebugPreference = $using:DebugPreference 
			$VerbosePreference = $using:VerbosePreference 
			$InformationPreference = $using:InformationPreference 
		# end of bug workaround

		# create our custom function within our runspace (note the using; more on that below)
		${function:Get-DummyItem} = $using:getDummyItemParallel
		
		# our pipeline variable is available as normal... here I add it to another variable so it's accessible when we delve into lower loops
		$currentItem = $_
		
		# do some processing.  Note the use of `using:` to access variables defined outside of our runspace.  These must be readonly within this runspace.
		$ipInfo = Get-DummyItem -Name $currentItem.Name
		$currentItem | Add-Member -Name 'Demo' -MemberType NoteProperty -Value "$using:appendString $ipInfo"
	}
	$output | Sort-Object Id
	
#...