PowerShell Repeatedly calling a function - function

Question

The task at hand is to compare permissions from a source folder with a target folder, and this for all its sub folders. I've already created the function that does this check on one folder, which returns $True or $False.
I would like to know if it's possible to create a function that calls itself to be executed on every sub folder it finds to call Test-ACLequalHC. So that when it blocks or errors out in one of the sub folders, due to permission issues or something else, it can still continue with the others.
Something like a crawler, if that makes sense. Ideally it would be great if it could run in parallel. I read that a Workflow is most suited for this, but I've never used it before.
Unfortunately it's not possible to just do $AllSubFolders = Get-ChildItem -Recurse followed by a foreach, because there are over thousands of files and folders under the root folder. So it needs to be dynamically so that we can do extra stuff on every folder it finds, like say if Test-ACLequalHC results in $False on one folder, we can still call other functions to set the permissions correct or add the result to a CSV.
Permission test:
Function Test-ACLequalHC {
[CmdletBinding(SupportsShouldProcess=$True)]
Param(
[parameter(Mandatory=$true,Position=0)]
[ValidateScript({Test-Path $_})]
[String]$Source,
[parameter(Mandatory=$true,Position=1)]
[ValidateScript({Test-Path $_})]
[String]$Target,
[parameter(Mandatory=$true,Position=2)]
[ValidateSet('Access','Owner','All')]
[String]$Type
)
Begin {
$Props = Switch ($Type) {
'Access' {'Access', 'AreAccessRulesProtected'}
'Owner' {'Owner'}
'All' {'sddl'}
}
}
Process {
$CompParams = #{
Property = $Props
ReferenceObject = Get-Acl $Source #| Sort-Object
DifferenceObject = Get-Acl $Target #| Sort-Object
PassThru = $True
}
$Result = Compare-Object #CompParams
if ($Result -ne $null) {
Write-Output $false
}
else {
Write-Output $True
}
}
}
It would be great if it could check files to, for inheritance and that no extra permissions are added. But I'll add that stuff later on myself if I find out how to make such a crawler thingy that digs its way through the folder structure.
Thank you for your help.

Answer 1

Ok, I think your aversion of doing Get-ChildItem -Recurse is something you're going to need to get over. If you are only looking at directories use the -directory switch for Get-ChildItem. It's a provider level switch so it will speed things up dramatically.
Next, what I think you need to consider is the Ad--Member cmdlet. Something like this:
$Source = C:\GoodFolder
$AllFolders = GCI C:\ -Directory -Recurse
$AllFolders | ForEach{Add-Member -InputObject $_ -NotePropertyName "ACLGood" -NotePropertyValue (Test-ACLequalHC $source $_.fullname all)}
Then you can just filter on that for folders that have issues and address them as needed.
$AllFolders | Where{!$_.ACLGood} | ForEach{ Do stuff to fix it }