Powershell – How recursive directory searches got better with PSv3…

In the old days, we ate dirt for dinner, brushed our teeth with sticks, used PowerShell v2 — and we *liked* it! 

There, that’s my tribute to Dana Carvey as “Grumpy Old Man”.  Google it, kids.

Anyway, I’ve got an absolute ton of old PowerShell scriptlets that I have lying about that I regularly cannibalize or resuscitate back into production.  And since we are in that squishy transitional period between PowerShell v2 and v3, I don’t always bother to check them for compatibility with v3 or update features in the script to take advantage of new capabilities.  But I hit on one v3 improvement the other day that solved a problem has bugged me so much for so long that I wanted to shout from the mountaintops about it!  And since I live in mostly-mountainless Michigan, the blog is the best I can do…

Really it’s such a little thing.  But it’s so overdue.

In the past, if you wanted to recursively inspect a folder structure on a remote server — for instance while fishing for explicit NTFS permissions on folders — you were forced to inspect all folders *and* files, no matter if you only wanted folders.  Basically, you had to ask for everything (all children folders and files, recursively), then parse the result to extract the folders (check psIsContainer) from the listing.  Here’s an example of this, similar to what you might see all around the internet:

# For PowerShell v2
$containers = Get-ChildItem -path $TopPath$CurrentParent -recurse | ? {$_.psIscontainer -eq $true}

 Of course, this could be incredibly wasteful in processing, network bandwidth, time, etc…   All this time I’ve always wished there was a way in my loops to just ask for ONLY the folders, to save all of that waste.  Thankfully, this has arrived with v3.  Behold:

# For PowerShell v3
$containers = Get-ChildItem -Directory -path $TopPath$CurrentParent -recurse

 This has significantly sped up some of my analysis scripts that I run in a large enterprise, cutting as much as half a day off of some of my execution times (I did mention it was large).  So really what this means is that I have to start spending more spare time looking through the v2/v3 differences…  But I won’t have any spare time until I implement more v3 changes…  Quite a conundrum… 

😉

 

2017-07-27T00:01:04+00:00 April 17th, 2013|Uncategorized|

About the Author:

Jeremy is just a regular guy that likes to occasionally tell the world about stuff.