Deletes all externally sourced NuGet packages from an Azure DevOps Artifacts feed

DeleteAllExternalAzureDevopsNugetArtifacts.ps1

param(
    [Parameter(Mandatory=$True, Position=0)]
    [System.String]
    $organization,

    [Parameter(Mandatory=$True, Position=1)]
    [System.String]
    $feedName,

    [Parameter(Mandatory=$True, Position=2)]
    [System.String]
    $connectionToken
)

$apiVersion = "7.1-preview.1"
$base64AuthInfo = [System.Convert]::ToBase64String([System.Text.Encoding]::ASCII.GetBytes(":$($connectionToken)"))

$FeedsUrl = "https://feeds.dev.azure.com/$organization/_apis/Packaging/Feeds?api-version=$apiVersion"     
$Feeds = (Invoke-RestMethod -Uri $FeedsUrl -Method Get -UseDefaultCredential -Headers @{Authorization=("Basic {0}" -f $base64AuthInfo)})
$feedId = $($Feeds | Where-Object {$_.value.name -eq $feedName} | Select-Object -First 1).value.id

if ($null -ne $feedId) {
    $PackagesUrl = "https://feeds.dev.azure.com/$organization/_apis/Packaging/Feeds/$feedId/Packages?api-version=$apiVersion"     
    $PackagesInFeed = (Invoke-RestMethod -Uri $PackagesUrl -Method Get -UseDefaultCredential -Headers @{Authorization=("Basic {0}" -f $base64AuthInfo)})
    
    $packagesId = $PackagesInFeed.value.id
    
    ForEach ($PI in $packagesId) {
        $PackageNameUrl = "https://feeds.dev.azure.com/$organization/_apis/Packaging/Feeds/$feedId/Packages/$($PI)?api-version=$apiVersion"                 
        $PackageNames = (Invoke-RestMethod -Uri $PackageNameUrl -Method Get -UseDefaultCredential -Headers @{Authorization=("Basic {0}" -f $base64AuthInfo)})
    
        $UpstreamSource = $PackageNames.versions.directUpstreamSourceId
    
        if ($null -ne $UpstreamSource) {
            $PackageVersionUrl = "https://feeds.dev.azure.com/$organization/_apis/Packaging/Feeds/$feedId/Packages/$($PI)/Versions?api-version=$apiVersion"                 
            $PackageVersions = (Invoke-RestMethod -Uri $PackageVersionUrl -Method Get -UseDefaultCredential -Headers @{Authorization=("Basic {0}" -f $base64AuthInfo)}) 
    
            $VersionsId = $PackageVersions.value.version
            $packageName = $PackageNames.name
    
            Write-Host "Deleting Package: $packageName"
            Write-Host "Versions: $($VersionsId -join ", ")"
            Write-Host
    
            ForEach ($VI in $VersionsId) {
                $DeleteUrl = "https://pkgs.dev.azure.com/$organization/_apis/Packaging/Feeds/$feedId/nuget/Packages/$($packageName)/Versions/$($VI)?api-version=$apiVersion"                   
                $Member = (Invoke-RestMethod -Uri $DeleteUrl -Method DELETE -UseDefaultCredential -Headers @{Authorization=("Basic {0}" -f $base64AuthInfo)})
            }
    
        } elseif ($targetTask.result -eq "Failed") {
            Write-Host ("This is package not from upstream source!")
        }    
    }

} else {
    Write-Host "Feed '$feedName' could not be found!"
}