# from http://blogs.technet.com/b/heyscriptingguy/archive/2010/09/14/use-powershell-to-script-changes-to-the-sharepoint-web-config-file.aspx


function Enable-SPBlobCache {

param(

    [Parameter(Mandatory=$true, ValueFromPipeline=$true, Position=0)]
    [Microsoft.SharePoint.PowerShell.SPWebApplicationPipeBind]
    $WebApplication
)

	process {
	
		$WebApp = $WebApplication.Read()
		# SPWebConfigModification to enable BlobCache
		$configMod1 = New-Object Microsoft.SharePoint.Administration.SPWebConfigModification
		$configMod1.Path = "configuration/SharePoint/BlobCache" 
		$configMod1.Name = "enabled" 
		$configMod1.Sequence = 0
		$configMod1.Owner = "BlobCacheMod" 
		## SPWebConfigModificationType.EnsureChildNode -> 0
		## SPWebConfigModificationType.EnsureAttribute -> 1
		## SPWebConfigModificationType.EnsureSection -> 2
		$configMod1.Type = 1
		$configMod1.Value = "true" 
	
		# SPWebConfigModification to enable client-side Blob caching (max-age)
		$configMod2 = New-Object Microsoft.SharePoint.Administration.SPWebConfigModification
		$configMod2.Path = "configuration/SharePoint/BlobCache" 
		$configMod2.Name = "max-age" 
		$configMod2.Sequence = 0
		$configMod2.Owner = "BlobCacheMod" 
	
		## SPWebConfigModificationType.EnsureChildNode -> 0
		## SPWebConfigModificationType.EnsureAttribute -> 1
		## SPWebConfigModificationType.EnsureSection -> 2
	
		$configMod2.Type = 1
		$configMod2.Value = "86400" 
		
		
		# SPWebConfigurationModification to move blobstore location
		$configMod3 = New-Object Microsoft.SharePoint.Administration.SPWebConfigModification
		$configMod3.Path = "configuration/SharePoint/BlobCache" 		
		$configMod3.Name = "location"
		$configMod3.Sequence = 0
		$configMod3.Owner = "BlobCacheMod" 
		$configMod3.Type = 1
		$configMod3.Value = "C:\Blobcache2\14"		
		
		
	
		# Add mods, update, and apply
	
		$WebApp.WebConfigModifications.Add( $configMod1 )
		$WebApp.WebConfigModifications.Add( $configMod2 )
		$WebApp.WebConfigModifications.Add( $configMod3 )
		$WebApp.Update()
		$WebApp.Parent.ApplyWebConfigModifications()
	
	}


} 


function Disable-SPBlobCache {

	param(
	
		[Parameter(Mandatory=$true, ValueFromPipeline=$true, Position=0)]
		[Microsoft.SharePoint.PowerShell.SPWebApplicationPipeBind]
		$WebApplication
	
	)
	
		process {
			$WebApp = $WebApplication.Read()
			$mods = @()
			foreach ( $mod in $WebApp.WebConfigModifications ) {
				if ( $mod.Owner -eq "BlobCacheMod" ) {
					$mods += $mod
				}
		}
		
			foreach ( $mod in $mods ) {
				[void] $WebApp.WebConfigModifications.Remove( $mod )
			}
		
			$WebApp.Update()
			$WebApp.Parent.ApplyWebConfigModifications()
		}

}