PowerShell Setup for SharePoint 2010 Diagnostics

STSADM still ships with SharePoint 2010 but has been replaced with PowerShell as the preferred scripting engine for SharePoint. I rarely write SharePoint scripts, but I do often use these tools for testing. Lately I have been testing a lot of upgrade scenarios. To make the best use of PowerShell as a SharePoint diagnostic environment I have a few tips.

PowerShell Community Extensions – Get and install these extensions as they will make your PowerShell environment much nicer. Once installed, edit the (My)Documents\WindowsPowerShell\Profile.ps1 file to uncomment the Visual Studio environment variables. It is necessary to add ’10.0’ at the front of the comma separated list for “VisualStudioVersion”.

Auto Load the SharePoint Extension – Add the following line to your PowerShell profile.ps1 file to automatically load the SharePoint extension for PowerShell in every shell you launch.

& "C:\Program Files\Common Files\Microsoft Shared\Web Server xtensions\14\CONFIG\POWERSHELL\Registration\sharepoint.ps1"

PowerShell Threading Model and Extension Object Disposal – Each line entered in PowerShell is run by a single thread. This creates some problems because many SharePoint objects are attached to IIS COM objects and need disposal. The SharePoint extension methods for PowerShell deal with this to some extent. You get objects that appear to be the SharePoint .Net objects but are in some way disconnected from the IIS backend. The result is that some of the methods and properties of the object may not function. When you call these methods you may get a response that the object has been disposed.

Workaround for the Extension Object Disposal Problem - To get around this problem, use PowerShell to instantiate the .Net objects directly. This was possible with SharePoint 2007. When doing this, the object and the disposal should be contained in a single line of PowerShell (one thread). Here is an example of the threading model in practice:

PS> [Guid]$featureId="6d44695f-ca99-4c27-9b6b-2a39c62357a1"
PS> $site=new-object Microsoft.SharePoint.SPSite("http://server/sitecollection"); site.RootWeb.Features[$featureId];$site.Dispose()

This example can be used to show the version of a particular feature. I have used this a lot while studying the new feature upgrade capabilities in SharePoint 2010. Upgrade is a subject for another time.

Finding the Right Cmdlet – Microsoft has yet to publish the PowerShell documentation for the SharePoint extension. It is possible to dig the list of Cmdlets from looking at the SharePoint API documentation. I find it easier to just play with them in PowerShell. I use the following help function to make it easier to find the Cmdlets I need. You can put this in your PowerShell profile.ps1 file to make it available.

function findhelp([string]$part)
{
help > c:\temp\helpjunk.txt
$lookingFor = ".*" + $part + ".*"
cat c:\temp\helpjunk.txt where {$_ -match $lookingFor}
}