PowerShell - Checking if OU exists

After starting work on a function, I stumbled across a StackOverflow article and wanted to expand on that post.

That simple method only works well if the LDAP Path is clean. If you’re possibly working with unclean data (or typo the DC structure), you’ll need to catch your errors.

[string] $Path = 'OU=foo,OU=test,DC=domain,DC=com'
try {
	$ou_exists = [adsi]::Exists("LDAP://$Path")
} catch {
	# If invalid format, error is thrown.
	Throw("Supplied Path is invalid.`n$_")
}

if (-not $ou_exists) {
	Throw('Supplied Path does not exist.')
} else {
	Write-Debug "Path Exists:  $Path"
}

Since DC=domain,DC=com doesn’t exist (or at least isn’t accessible for an LDAP query), I get the following outputted from the above example; which is expected, since I threw the Supplied Path is invalid error (you can handle the error however you want):

Supplied Path is invalid.
Exception calling "Exists" with "1" argument(s): "A referral was returned from the server.
[...]

In my case, I only work within a particular OU in our Domain, so I’ve made it so my $Path can be abbreviated. Here’s how I handle things:

[string] $RootOU = 'OU=test,DC=domain,DC=com'
[string] $Path = 'OU=foo'
try {
    $ou_exists = [adsi]::Exists("LDAP://$Path")
} catch {
    # If invalid format, error is thrown.
    Write-Debug "Supplied Path is invalid.`n$_"
    # It's probably the abbreviated version, so let's tack on the Root OU and confirm exists.
    Write-Debug 'Placing Path in Root OU and re-verifying ...'
    $Path = "$Path,$RootOU"
    try {
        $ou_exists = [adsi]::Exists("LDAP://$Path")
    } catch {
        Throw("Supplied Path is not valid, nor is our attempt to place it in the Root OU:`n$Path")
    }
}

if (-not $ou_exists) {
    Throw("Supplied Path does not exist:`n$Path")
} else {
    Write-Debug "Path Exists (1):  $Path"
}

If the OU=foo,OU=test,DC=domain,DC=com OU exists, the following will be outputed, in the above example:

DEBUG: Path Exists (2):  OU=foo,OU=test,DC=domain,DC=com

Hope this helps others out there. Cheers!