Recursively Disabling a SharePoint Feature throughout a Farm

I'm working on a large SharePoint migration project at the moment. It's required quite a bit of PowerShell to automate tasks that ensure the project is a success.

One of those tasks was to find everywhere a feature was activated through the farm, and optionally disable the feature. Whenever we disable a feature throughout the farm, we need to keep a report of all the places the feature was previously enabled (there's about ten thousand webs in this farm).

So I wrote a script, that does exactly that! The script takes a feature-id, an SPWeb and two switches as parameters, and returns an object collection that records details about the feature instances disabled (feature id and display name, the web url, the feature status and the time it was last activated).

The two parameters, -Recurse, and -Report, control the scripts function. The -Recurse parameter tells the script to check all of the input webs sub-webs. The -ReportOnly parameter tells the script to... well, create a report of everywhere the feature is currently active, without actually disabling it!

Here's the function:

function Outst-SPFeature            
{            
 [CmdletBinding()]                        
    Param(                          
            [parameter(Mandatory=$true,Position = 0,valueFromPipeline=$true)][Microsoft.SharePoint.SPWeb]$Web,            
            [parameter(Mandatory=$true)][string]$FeatureId,            
            [parameter(Mandatory=$false)][switch]$Recurse,            
   [parameter(Mandatory=$false)][switch]$ReportOnly            
        )            
 #Define an object that can store the features properties             
 $FeatureInfo = New-Object psobject            
 $FeatureInfo | Add-Member -MemberType NoteProperty -Name "Id" -value ""
 $FeatureInfo | Add-Member -MemberType NoteProperty -Name "DisplayName" -value ""
 $FeatureInfo | Add-Member -MemberType NoteProperty -Name "WebUrl" -value ""
 $FeatureInfo | Add-Member -MemberType NoteProperty -Name "Status" -value ""
 $FeatureInfo | Add-Member -MemberType NoteProperty -Name "TimeActivated" -value ""             
 #create an empty array variable            
 $matches = @();            
             
 Write-Host "Checking web"$Web.Url -f Green -b Yellow;#pipe the list of features ($web.Features) to the Where-Object cmdlet (aliased as '?'), and look for a feature with the same FeatureId that was passed to the script as a parameter            
 $f = $Web.Features | ?{$_.DefinitionId -like $FeatureId}            
    #If the feature was found, $f won't be null            
 if($f -ne $null)            
 {            
        #If the feature was found, check the SPFeature.Definition.Status property, to see if the feature is activated (online)            
  if($f.Definition.Status -eq "Online")            
  {            
   Write-Host "Disabling feature,"$f.Definition.DisplayName -f Green            
            #If the feature is online, then record the features details in a new custom object (this will get returned at the end of the function)            
   $fm = $FeatureInfo | Select-Object *;            
   $fm.Id = $f.Definition.Id;            
   $fm.DisplayName = $f.Definition.DisplayName;            
   $fm.WebUrl = $Web.Url;            
   $fm.Status = $f.Definition.Status;            
   $fm.TimeActivated = $f.TimeActivated            
   #Add the custom object to the $matches array (a list that will contain a custom object for each instance of a feature found)            
   $matches += $fm;            
    #Check the -ReportOnly switch. If the switch wasn't passed to the function, it will be false.             
   if($ReportOnly -eq $false)            
   {            
                #Disable the feature            
    Disable-SPFeature -Identity $f.Definition.Id -Url $Web.Url -Confirm:$false
   }               
  }            
 }            
  #Check the -Recurse switch. If the switch wasn't passed to the function, it will be false. Also check if the web has any sub-webs. If both of these checks are true, then check the sub-webs            
 if($Recurse -eq $true -and $Web.Webs.Count -gt 0)            
 {            
  Write-Host "Checking sub webs" -f Blue            
  foreach($sw in $Web.Webs)            
  {   #Here we want to call the same function again, against the sub-webs. The $matches variable is incremented with the results returned from the new call to the function.             
   if($ReportOnly -eq $false)            
   {            
    $matches += Outst-SPFeature -Web $sw -FeatureId $FeatureId -Recurse            
   }            
   else            
   {            
    $matches += Outst-SPFeature -Web $sw -FeatureId $FeatureId -Recurse -ReportOnly            
   }                 
  }              
 }            
 #The $matches array (containing the list that contains custom objects for each instance of a feature found) is returned.            
 return $matches;            
}            

And this is how it can be called:

#Run this command to disable the feature on all webs in all webapplications.            
$disabledfeature = Get-SPWebApplication | Get-SPSite -Limit All | Get-SPweb -Limit All |Foreach {Outst-SPFeature $_ -FeatureId "a5557f3e-102c-401e-9eae-1e7fcf4340d0" -Recurse}

And this is how you export the results to an xml file that can reloaded at a later time:

#Run this command to disable the feature on all webs in all webapplications, and save a report of all the feature instances that were disabled to C:\Temp\DisabledFeatureReport.xml
Get-SPWebApplication | Get-SPSite -Limit All | Get-SPweb -Limit All |Foreach {Outst-SPFeature $_ -FeatureId "a5557f3e-102c-401e-9eae-1e7fcf4340d0" -Recurse} | Export-Clixml -Path C:\Temp\DisabledFeatureReport.xml