Introduction to Advanced PowerShell

PowerShell is not just a scripting language but a full-fledged automation framework. This guide covers advanced topics that will help experienced users optimize workflows, improve performance, and enhance security.

Key Topics Covered

• Advanced Scripting Techniques
• Performance Optimization
• Security and Hardening
• Custom Modules and Advanced Functions
• PowerShell Remoting
• Working with APIs and Web Services
• Debugging and Logging

Advanced Scripting Techniques

Using Script Blocks Effectively

$scriptBlock = { Get-Process | Where-Object { $_.CPU -gt 10 } }
Invoke-Command -ScriptBlock $scriptBlock

Dynamic Parameters

function Get-UserInfo {
    param(
        [Parameter(Mandatory)]
        [string]$Username
    )
    Get-ADUser -Filter {SamAccountName -eq $Username}
}

Using Background Jobs

Start-Job -ScriptBlock { Get-Service }
Get-Job | Receive-Job

Performance Optimization

Using Efficient Loops

$LargeArray | ForEach-Object -Parallel { $_ * 2 }

Avoiding Unnecessary Object Creation

$Processes = Get-Process | Select-Object -Property Name, Id, CPU

Optimizing Pipeline Execution

Get-Service | Where-Object Status -eq 'Running' | Select-Object Name, DisplayName

Security and Hardening

Execution Policy Management

Set-ExecutionPolicy RemoteSigned -Scope CurrentUser

Secure Credential Handling

$Cred = Get-Credential
Invoke-Command -ComputerName Server01 -Credential $Cred -ScriptBlock { Get-Process }

Auditing and Logging

Set-PSReadlineOption -HistorySaveStyle SaveAtExit
Get-EventLog -LogName Security -Newest 10

Custom Modules and Advanced Functions

Creating Custom Modules

New-ModuleManifest -Path "C:\PowerShell\MyModule.psd1"

Using Private Functions in Modules

function PrivateFunction {
    Write-Output "This is private"
}
Export-ModuleMember -Function * -Exclude PrivateFunction

PowerShell Remoting

Enabling and Configuring Remoting

Enable-PSRemoting -Force

Secure Remote Sessions

New-PSSession -ComputerName Server01 -Credential (Get-Credential)

Working with APIs and Web Services

Sending API Requests

$Response = Invoke-RestMethod -Uri "https://api.github.com/repos/microsoft/PowerShell" -Method GET
$Response | Format-List

Parsing JSON Responses

$Data = ConvertFrom-Json -InputObject $Response
$Data.full_name

Debugging and Logging

Using Debugging Tools

Set-PSDebug -Trace 2

Writing Logs to Files

"Log entry: $(Get-Date)" | Out-File "C:\Logs\script.log" -Append

Best Practices for Advanced Users

General Guidelines

• Use Try-Catch-Finally for robust error handling
• Implement logging in automation scripts
• Secure scripts with least privilege principles
• Optimize scripts for performance and efficiency

This guide provides deep insights into advanced PowerShell topics. Keep refining your skills to become an expert in automation and scripting!