Get-WSLPaths.ps1

## Get-WSLPaths
<#
    .SYNOPSIS
        Gets paths and names of WSL distributions installed from Windows Store.
        If no parameters supplied, it prints all installed WSL distributions.
    .EXAMPLE
        PS> Get-WSLPaths debian
        PackageFullName : TheDebianProject.DebianGNULinux_1.1.6.0_x64__76v4gfsz19hv4
        InstallLocation : C:\Program Files\WindowsApps\TheDebianProject.DebianGNULinux_1.1.6.0_x64__76v4gfsz19hv4
        rootfsPSPath    : ${env:LOCALAPPDATA}\Packages\TheDebianProject.DebianGNULinux_76v4gfsz19hv4\LocalState\rootfs
        rootfsPath      : C:\Users\User\AppData\Local\Packages\TheDebianProject.DebianGNULinux_76v4gfsz19hv4\LocalState\rootfs
#>

#Requires -Version 5
#Requires -Module Appx

function Get-WSLPaths
{
    [CmdletBinding()]
    param([string][parameter(Mandatory=$false,ValueFromPipeline=$True)]$DistroName)

    Set-StrictMode -Version 'Latest'

    # Packages location (Literal string for printing output)
    $packagesLiteralPath = [string]'${env:LOCALAPPDATA}\Packages'
    # Resolved packages location
    $packagesPath        = (Resolve-Path "${env:LOCALAPPDATA}\Packages").Path
    # Sub-directory containing rootfs
    $rootfsRelativePath  = 'LocalState\rootfs'

    if ($DistroName)
    {
        $distroPackages = Get-AppxPackage | Where-Object{$_.PackageFullName -imatch $DistroName}
    }
    else
    {
        # List of known WSL distros from Windows Store
        $distros = @(
            "TheDebianProject",
            "KaliLinux",
            "openSUSELeap42",
            "openSUSELeap15",
            "SUSELinuxEnterpriseServer12",
            "SUSELinuxEnterpriseServer15",
            "UbuntuonWindows",
            "Ubuntu18.04onWindows",
            # Third-Party published WSL distros
            "WhitewaterFoundryLtd.Co.16571368D6CFF",        # Debian fork
            "WhitewaterFoundryLtd.Co.FedoraRemixforWSL",    # Fedora fork
            "WhitewaterFoundryLtd.Co.WLinuxEnterprise"      # Scientific fork
        )

        $distroPackages = Get-AppxPackage -User "$env:USERNAME" | Where{$_ | Select-String ($distros.split()-join('|'))}
    }

    [scriptblock]$distroProperties = {
        if ($null -ne $distroPackages)
        {
            foreach($distro in ($distroPackages))
            {
                $rootfsPSPath = [io.path]::combine($PackagesLiteralPath,
                                                   $distro.PackageFamilyName,
                                                   $rootfsRelativePath)
                $rootfsPath   = [io.path]::combine($PackagesPath,
                                                   $distro.PackageFamilyName,
                                                   $rootfsRelativePath)
                Add-Member -InputObject $distro -MemberType NoteProperty -Name rootfsPSPath  -Value $rootfsPSPath
                Add-Member -InputObject $distro -MemberType NoteProperty -Name rootfsPath    -Value $rootfsPath
                $distro | Select-Object -Property PackageFullName, InstallLocation, rootfsPSPath, rootfsPath
            }
        }
    }

    Invoke-Command $distroProperties | Format-List # TODO: psformat xml to query as objects instead of spewing out string tables.

}

# If this script is invoked directly as opposed to being dot-sourced;
# invoke the embedded function relaying any arguments passed
if ($MyInvocation.ExpectingInput)
{
    # True if we have ValueFromPipeLine $input (ExpectingInput)
    $input | Get-WSLPaths @args
}
elseif (-not ($MyInvocation.InvocationName -eq '.' -or $MyInvocation.Line -eq ''))
{
    # True if not dot-sourced or is invoked directly (empty invocation line)
    Get-WSLPaths @args
}