# A script to reset the SharePoint 2010 Disk Based Cache for BLOBs

# Example: .\Reset-Blob-Cache.ps1 http://MySiteCollection
            (http://mysitecollection/)
        

# Loads the SharePoint 2010 PowerShell extensions so we can easily 



# get a reference to our dlls.

try

{

    if(((Get-PSSnapin | foreach {$_.Name}) -contains "Microsoft.SharePoint.PowerShell") -eq $false)

    {

      Add-PSSnapIn Microsoft.SharePoint.PowerShell -ErrorAction Stop

    }

}

catch

{

    Write-Host-ForegroundColor "red" "This script only works on machines with SharePoint 2010 installed.`n"

    Exit

}



# Use Reflection to get a reference to our dlls.

try

{

    $spAssembly = [System.Reflection.Assembly]::GetAssembly([Microsoft.SharePoint.SPSite])

    [System.Reflection.Assembly]::Load($spAssembly) | Out-Null

}

catch

{

    Write-Host-ForegroundColor "red" "Could not locate the SharePoint Assemblies.`n"

    Exit

}



# You must provide a site upon which to execute the cache reset.

if ($args.length -ne 1)

{

    Write-Host "Expected 1 arguments:"

    Write-Host "<site_url>"

    exit

}



$site_url = $args[0]



try

{

    $site = Get-SPSite -Identity $site_url -ErrorAction Stop

}

catch

{

    Write-Host-ForeGround 'Red' "$_"

    Write-Host-ForeGround 'Red' "Please correct the arguments and try again.`n`n"

    Exit

}



$warning = "This will clear the blob cache for all sites in this application, on all WFEs in the farm. `nPress 'y' to continue:"



Write-Host-ForeGround 'Yellow' -noNewLine $warning 



$key = $host.UI.RawUI.ReadKey("NoEcho,IncludeKeyUp")



if ($key.Character -ine "y")

{

    Write-Host "`nYou chose not to flush the cache."

    exit

}



Write-Host "`nFlushing..."

[Microsoft.SharePoint.Publishing.PublishingCache]::FlushBlobCache($site.WebApplication)



Write-Host "Flushed Cache for:" $site.WebApplication.Name