Remove workflow

Previously I showed you how to add a workflow and task list to all of your subsites through a powershell script, now let’s say what was done must also be able to be undone. So naturally here’s a powershell script to remove your Workflow and task list from all sub webs.

Section One (Set up)

#get the site url to deploy workflow to

param($siteUrl=$(read-host "Please provide web app url of the list to be delete (EG:'http://Wingtip'):"))

#ensure that user provided site url parameter

if($siteUrl -eq $null -or $siteUrl -eq '')

{

    throw "You must specify your server name. Value provided was null/empty."

}

#function to load SharePoint Powershell snap in

function LoadSharePointPowerShellEnviroment

{

 #clear the screen of pevious output

Clear-Host

 write-host "Setting up Powershell enviroment for Sharepoint" -foregroundcolor Blue

 Add-PSSnapin "Microsoft.Sharepoint.PowerShell" -ErrorAction SilentlyContinue

 Write-host "Sharepoint PowerShell Snapin loaded." -foregroundcolor Green

}

#call sharepoint plugin function

LoadSharePointPowerShellEnviroment

Section Two(Declare constants)

#get site using parameter

$site = Get-SPSite($siteUrl)

#Name of task list to delete

$listName = "Approval Tasks"

#approval workflow ID, specified in elements file of workflow

$APPROVALWORKFLOWID = [GUID]("64f076cb-a5f8-4ee7-9ef4-54820d291886");

Section Three(remove workflow function)

#remove workflow function

function RemoveAssociation($web, $listName)

{

      #library the workflow is runnion on

      $listInstance = $web.Lists.TryGetList($listName)

     

      #make sure the library exists

      if($listInstance -ne $null)

      {    

            #get the number of workflows running on library

            $i = $listInstance.WorkflowAssociations.Count - 1

            While($i -gt -1)

            {

                  #if workflow is ours, and it has 0 running then remove it.

                  if($listInstance.WorkflowAssociations[$i].BaseTemplate.Id.Equals($APPROVALWORKFLOWID) -and

                     $listInstance.WorkflowAssociations[$i].RunningInstances -eq 0)

                  {

                        Write-Host "Removing Workflow " $listInstance.WorkflowAssociations[$i].Name "From" $listName -ForegroundColor DarkGreen

                        $listInstance.WorkflowAssociations.Remove($listInstance.WorkflowAssociations[$i])                    

                  }

                  $i--

            }

      }    

      $listInstance = $null

      $web.Dispose()

}

Section Three(traverse all webs and remove list)

#itterate through all subsites

foreach ($web in $site.AllWebs)

{

      #get the list you whish to delete

      $listToDelete = $web.Lists.TryGetList($listName)

     

      #if the list exists delete it

      if($listToDelete -ne $null)

    {

            Write-Host $listToDelete.RootFolder $listName " has been deleted" -ForegroundColor Green

        $web.Lists.Delete($listToDelete.ID)

            $web.Update()

    }

     

      #remove the workflow from libraries

      RemoveAssociation $web "Pages"

      RemoveAssociation $web "Images"

      RemoveAssociation $web "Documents"

           

    $web.Dispose()

}

$site.Dispose()

Write-Host "Script Complete" -ForegroundColor Blue