Understanding Import-Clixml in PowerShell

Welcome back to Wahman’s PowerShell Blog! Today we’ll explore an incredibly useful cmdlet that makes persisting and retrieving objects in PowerShell a breeze: Import-Clixml.

What is Import-Clixml?

According to Microsoft, the Import-Clixml cmdlet Imports a CLIXML file and creates corresponding objects in PowerShell. This means you can serialize complex objects to XML using Export-Clixml, store them, and later bring them back to life as fully usable PowerShell objects using Import-Clixml.

Let’s dive into some examples, ranging from beginner to more advanced use cases.

Example 1: Saving and Restoring a Simple Object

# Export a simple object
$info = Get-Process | Select-Object -First 1
$info | Export-Clixml -Path "C:\temp\process.xml"

# Later or in another session, import it
$restoredInfo = Import-Clixml -Path "C:\temp\process.xml"
$restoredInfo | Format-List

This demonstrates how easy it is to save and restore objects without losing their structure or members.

Example 2: Sharing Configuration Between Scripts

# Export some custom configuration
$config = @{ Server = "srv01"; Port = 443; UseSSL = $true }
$config | Export-Clixml -Path "C:\temp\config.xml"

# Import configuration in another script
$importedConfig = Import-Clixml -Path "C:\temp\config.xml"
Write-Host "Connecting to $($importedConfig.Server) on port $($importedConfig.Port) with SSL: $($importedConfig.UseSSL)"

This is a great technique for sharing parameters or settings between scripts.

Example 3: Saving Credential Objects Securely

# Save credentials to a secure file (encrypted using your user context)
$cred = Get-Credential
$cred | Export-Clixml -Path "C:\temp\cred.xml"

# Import credentials later
$restoredCred = Import-Clixml -Path "C:\temp\cred.xml"
Invoke-Command -ComputerName "srv01" -Credential $restoredCred -ScriptBlock { hostname }

This is a powerful way to safely store credentials for automation tasks (note: only usable by the same user on the same computer).

Example 4: Automation and Complex Object Exchange

# Assume this function runs on remote systems and returns a complex object
function Get-SystemInfo {
    return [PSCustomObject]@{
        OS = (Get-CimInstance Win32_OperatingSystem).Caption
        Memory = (Get-CimInstance Win32_ComputerSystem).TotalPhysicalMemory / 1MB
        Uptime = (Get-CimInstance Win32_OperatingSystem).LastBootUpTime
    }
}

# Save the results to a file
$sysInfo = Get-SystemInfo
$sysInfo | Export-Clixml -Path "C:\temp\sysinfo.xml"

# Later on another system, restore and process it
$restoredSysInfo = Import-Clixml -Path "C:\temp\sysinfo.xml"
Write-Output "System: $($restoredSysInfo.OS), Memory: $([math]::Round($restoredSysInfo.Memory)) MB, Uptime: $($restoredSysInfo.Uptime)"

This use case showcases how to exchange structured information between systems or store data from long-running processes for processing later.

Summary

Import-Clixml is a powerful tool to persist and retrieve objects with full fidelity, making it ideal for automation, configuration management, credentials, and more.

Happy scripting, and I will see you in the next post!