configure-powershell.ps1

#!/usr/bin/env pwsh

#region functions
function Write-Log {
    param( [string] $msg)
    "$(Get-Date -Format FileDateTimeUniversal) : $msg" | Write-Host
}
function Exit-WithError {
    param( [string]$msg )
    Write-Log "There was an exception during the process, please review..."
    Write-Log $msg
    Exit 2
}
#endregion

#region main
# Install PowerShell prerequisites
$nugetPackage = Get-PackageProvider | Where-Object Name -eq 'NuGet'

if ($null -eq $nugetPackage) {
    Write-Log "Installing NuGet PowerShell package provider..."

    try {
        Install-PackageProvider -Name NuGet -MinimumVersion 2.8.5.201 -Force 
    }
    catch {
        Exit-WithError $_
    }
}

$nugetPackage = Get-PackageProvider | Where-Object Name -eq 'NuGet'
Write-Log "NuGet Powershell Package Provider version $($nugetPackage.Version.Major).$($nugetPackage.Version.Minor).$($nugetPackage.Version.Build).$($nugetPackage.Version.Revision) is already installed..."

$repo = Get-PSRepository -Name PSGallery
if ( $repo.InstallationPolicy -eq 'Trusted' ) {
    Write-Log "PSGallery installation policy is already set to 'Trusted'..."
}
else {
    Write-Log "Setting PSGallery installation policy to 'Trusted'..."

    try {
        Set-PSRepository -Name PSGallery -InstallationPolicy Trusted    
    }
    catch {
        Exit-WithError $_
    }
}

$azModule = Get-Module -ListAvailable -Name Az*
if ($null -eq $azModule ) {
    Write-Log "Installing PowerShell Az module..."

    try {
        Install-Module -Name Az -AllowClobber -Scope AllUsers
    }
    catch {
        Exit-WithError $_
    }
}
else {
    Write-Log "PowerShell Az module is already installed..."
}

$azAutomationModule = Get-Module -ListAvailable -Name Az.Automation
Write-Log "PowerShell Az.Automation version $($azAutomationModule.Version) is installed..."

Exit 0
#endregion