Simplified PSWU

simplepswu.ps1

#requires -version 2.0


function Get-UpdateList {
<#
.Synopsis
Gets list of updates from Windows Update.
   
.PARAMETER  Criteria
The search criteria, see http://goo.gl/7nZSPs
Left at default, it will return all updates that have not yet
been installed, whether software or driver. Including Hidden
updates.

.NOTES
Returns an ISearchResult object (http://goo.gl/pvnUSM) named $ISearchResult
ISearchresult type - System.__ComObject#{d40cff62-e08c-4498-941a-01e25f0fd33c}
$ISearchResult.Updates contains an IUpdateCollection  - http://goo.gl/8C2dbb
WU error codes: http://goo.gl/cSWDY8

.EXAMPLE
Get-UpdateList | ft -AutoSize

ResultCode RootCategories     Updates            Warnings          
---------- --------------     -------            --------          
         2 System.__ComObject System.__ComObject System.__ComObject

.EXAMPLE
(Get-UpdateList).Updates.Count
40

Shows that there are 40 updates available.

.EXAMPLE
(Get-UpdateList).Updates | select maxdownloadsize, title | ft -AutoSize

MaxDownloadSize Title                                                                                                                
--------------- -----                                                                                                                
       10123467 Update for Windows Server 2012 R2 (KB2884846)                                                                        
         948931 Security Update for Windows Server 2012 R2 (KB2876331)                                                               
         517819 Security Update for Windows Server 2012 R2 (KB2892074)                                                               
         376647 Update for Windows Server 2012 R2 (KB2917993)
#>
    [CmdletBinding()]
    Param
    ([Parameter(Mandatory=$false, ValueFromPipeline=$false, Position=0)] $Criteria = "IsInstalled=0")

    try {
        $Searcher = New-Object -ComObject Microsoft.Update.Searcher
        $ISearchResult = $Searcher.Search($Criteria)
        $ISearchResult
    } catch {
        Write-Error "ERROR in Get-UpdateList"
        return $_
    } 
    
}


Function Show-UpdateList {
<#
.Synopsis
 Print a nice table of Updates not installed with some attribute info.

.Description
 Columns:
 
 THDRE
 |||||- "E" if EULA accepted, "-" if not
 ||||-- "R" if reboot required, "-" if not (frequently wrong!)
 |||--- "D" if the update has been downloaded, "-" if not
 ||---- "H" if the update is hiden, "-" if not
 |----- "S" if software, "D" if driver

.TODO
They don't sort properly;
#>
    [Cmdletbinding()]
    Param([Parameter(Mandatory=$true,Position=0,ValueFromPipeline=$true)]$ISearchResult)
    if ($ISearchResult.pstypenames -notcontains 'System.__ComObject#{d40cff62-e08c-4498-941a-01e25f0fd33c}') {
        Write-Error "$ISearchResult is not an ISearchResult object (http://goo.gl/pvnUSM)"
        break
    }
    Write-Output "$($ISearchResult.Updates.Count) updates available:"
    $ISearchResult.Updates |
    Select @{n='KB';e={$_.KbArticleIds}},
        #Update type 1 is software, type 2 is driver. http://goo.gl/VvV7tt
        @{n='T';e={if ($_.Type -eq 1) {"S"} ElseIf ($_.Type -eq 2) {"D"}}},
        @{n='H';e={if ($_.isHidden) {"H"} Else {"-"}}},
        @{n='D';e={if ($_.isDownloaded) {"D"} Else {"-"}}},
        @{n='R';e={if ($_.Rebootrequired) {"R"} Else {"-"}}},
        @{n='E';e={if ($_.EulaAccepted) {"E"} Else {"-"}}},
        @{n='MB';e={'{0:N0}' -f ($_.MaxDownloadSize/1MB)}},            
        @{n='Severity';e={$_.MsrcSeverity}},
        @{n='Published';e={$_.LastDeploymentChangeTime.ToShortDateString()}},
        #@{n='UID';e={$_.Identity.UpdateID}}, 
        #truncate title to 40 chars       
        @{n='Title';e={ if ($($_.Title.Length) -lt 40) {$_.Title} else {$($_.Title.Substring(0,37)) + "..."}}} |
    Sort -Property $_.LastDeploymentChangeTime | ft -AutoSize |out-string 
 
}


function Install-Update {
<#
.SYNOPSIS
    Downloads and installs updates

.NOTES
    Uses IUpdateDownloader http://goo.gl/hPK49j
    and IUpdateInstaller http://goo.gl/jeDijU
    WU error codes: http://goo.gl/cSWDY8
#>
    [CmdletBinding()]
    Param (
        [parameter(Mandatory=$true, ValueFromPipeline=$true)]$ISearchResult,
        [parameter(Mandatory=$false, ValueFromPipeline=$true)][switch]$OneByOne
        )    
    if ($ISearchResult.pstypenames -notcontains 'System.__ComObject#{d40cff62-e08c-4498-941a-01e25f0fd33c}') {
        Write-Error "$ISearchResult is not an ISearchResult object (http://goo.gl/pvnUSM)"
        break
    }

    $DesiredUpdates = New-Object -ComObject Microsoft.Update.UpdateColl
    $counter = 0
    foreach ($u in $ISearchResult.Updates) {
        $u.AcceptEula() 
        if (!$($u.IsHidden) -and !$($u.Rebootrequired)) { 
            $counter++
            $DesiredUpdates.Add($u) |out-null 
        }
        #Used for debugging. One update at a time.
        if ($OneByOne) { 
            if ($counter -gt 1) {break}
        }      
    }

    If ($DesiredUpdates.Count -lt 1) { 
        Write-Verbose "No updates to install!"
    } else {
        Write-Verbose "Downloading and installing $($DesiredUpdates.Count) updates" 
        $Downloader = New-Object -ComObject Microsoft.Update.Downloader
        $Downloader.Updates = $DesiredUpdates
        $DownloadResult = $Downloader.Download()
        #Resultcode 2-success, 3-success with errors. 
        #Using -contains instead of -in for PS v2 compat
        if (2,3 -notcontains $DownloadResult.ResultCode) {
            Write-Error "Downloader error HResult $($DownloadResult.HResult), resultcode $($DownloadResult.ResultCode)"
        } else {
            if ($DownloadResult.ResultCode -eq 3) {Write-Verbose "Downloaded with errors; beginning install."}
            if ($DownloadResult.ResultCode -eq 2) {Write-Verbose "Downloaded successfully; beginning install."}
            $Installer = New-Object -ComObject Microsoft.Update.Installer
            $Installer.Updates = $DesiredUpdates
            $InstallResult = $Installer.Install()
            switch ($InstallResult.ResultCode) {
                2 {Write-Verbose "Installed updates successfully."}
                3 {Write-Verbose "Installed updates swith errors."}
                default {Write-Error "Installer error $($InstallResult.HResult),resultcode $($InstallResult.ResultCode)"}
            }
        }        
    }
}

Get-UpdateList -Criteria "IsInstalled=0 AND RebootRequired=0 AND BrowseOnly=0 AND Type='Software'" | Install-Update

this version of PSWU only downloads and installs those updates which claim they won't need a reboot.

see https://goo.gl/7nZSPs for better understanding of the criteria on last line