A C# tool for cleaning up resource groups

cleanrg.cs

// -----------------------------------------------------------------------------
// Azure RG Janitor - Spectre Edition
// Run with:   dotnet run cleanup-rg.cs
// Targets:    .NET 10 Preview 4+
// -----------------------------------------------------------------------------

#:package Azure.Identity@1.*
#:package Azure.ResourceManager@1.*
#:package [email protected]

using Azure.Identity;
using Azure.ResourceManager;
using Azure.ResourceManager.Resources;
using Spectre.Console;

// ─────────────── settings ─────────────────────────────────────────────────────
const int MaxParallel = 10;               // limit concurrent deletions
// ──────────────────────────────────────────────────────────────────────────────

// 1️⃣  Select subscription
var arm = new ArmClient(new DefaultAzureCredential());
var subs = arm.GetSubscriptions().GetAllAsync();
var subList = new List<SubscriptionResource>();
await AnsiConsole.Status()
    .Spinner(Spinner.Known.Dots)
    .SpinnerStyle(Style.Parse("yellow"))
    .StartAsync("Fetching Azure subscriptions...", async ctx =>
    {
        await foreach (var s in subs)
            subList.Add(s);
    });

if (subList.Count == 0)
{
    AnsiConsole.MarkupLine("[red]❌ No subscriptions found.[/]");
    return;
}

var subChoices = subList.Select(s => $"{s.Data.DisplayName} ({s.Data.SubscriptionId})").ToList();
subChoices.Add("Cancel");
var selectedSub = AnsiConsole.Prompt(
    new SelectionPrompt<string>()
        .Title("Select an Azure subscription:")
        .AddChoices(subChoices)
        .UseConverter(x => x) // keep display as is
        .PageSize(10)
        .MoreChoicesText("[grey](Move up and down to reveal more subscriptions)[/]")
        .HighlightStyle("blue")
        .EnableSearch()
);
if (selectedSub == "Cancel")
{
    AnsiConsole.MarkupLine("[red]❌ Aborted by user.[/]");
    return;
}
var subIdx = subChoices.IndexOf(selectedSub);
var sub = subList[subIdx];

AnsiConsole.MarkupLine($"[bold blue]🔍  Scanning subscription [yellow]{sub.Data.DisplayName}[/]…[/]");

// 2️⃣  Find candidate resource groups
var matches = new List<ResourceGroupResource>();
await foreach (var rg in sub.GetResourceGroups().GetAllAsync())
{
    matches.Add(rg);
}

if (matches.Count == 0)
{
    AnsiConsole.MarkupLine("[green]✔ No resource groups match.[/]");
    return;
}

// 3️⃣  Pick list for resource groups
var rgChoices = matches.Select(rg => $"{rg.Data.Name}").OrderBy(name => name, StringComparer.OrdinalIgnoreCase).ToList();
matches = matches.OrderBy(rg => rg.Data.Name, StringComparer.OrdinalIgnoreCase).ToList();
var prompt = new MultiSelectionPrompt<string>()
    .Title($"Select resource groups to delete ([yellow]{matches.Count}[/] found):")
    .NotRequired()
    .PageSize(10)
    .InstructionsText("[grey](Press [blue]<space>[/] to toggle, [green]<enter>[/] to accept, type to search)[/]")
    .AddChoices(rgChoices);

// foreach (var choice in rgChoices)
//     prompt.Select(choice); // pre-select all

var selectedRgs = AnsiConsole.Prompt(prompt) ?? rgChoices;
AnsiConsole.MarkupLine($"[grey]Selected resource groups:[/]");
foreach (var name in selectedRgs)
    AnsiConsole.MarkupLine($"  [yellow]{name}[/]");
if (selectedRgs.Count == 0)
{
    AnsiConsole.MarkupLine("[red]❌ Aborted – nothing selected.[/]");
    return;
}

matches = matches.Where(rg => selectedRgs.Contains(rg.Data.Name)).OrderBy(rg => rg.Data.Name, StringComparer.OrdinalIgnoreCase).ToList();

// 1️⃣  pretty-print the list
var table = new Table()
    .Border(TableBorder.Rounded)
    .AddColumn("#")
    .AddColumn("Name");

int idx = 1;
foreach (var rg in matches)
    table.AddRow(idx++.ToString(), rg.Data.Name);

AnsiConsole.Write(table);

// 2️⃣  confirmation
bool proceed = AnsiConsole.Confirm(
    $"Delete [yellow]{matches.Count}[/] resource group(s) shown above?", defaultValue: false);

if (!proceed)
{
    AnsiConsole.MarkupLine("[red]❌ Aborted – nothing deleted.[/]");
    return;
}

// 3️⃣  delete with a progress bar
AnsiConsole.MarkupLine("[bold]🗑  Deleting…[/]");

using var gate = new SemaphoreSlim(MaxParallel);
await AnsiConsole.Progress()
    .AutoClear(true)
    .Columns(
    [
        new TaskDescriptionColumn(),
        new ProgressBarColumn(),
        new SpinnerColumn(),
        new ElapsedTimeColumn(),
    ])
    .StartAsync(async ctx =>
    {
        var overallTask = ctx.AddTask("Overall progress", maxValue: matches.Count);
        var rgTasks = matches.ToDictionary(
            rg => rg.Data.Name,
            rg => ctx.AddTask($"[grey]Deleting:[/] [yellow]{rg.Data.Name}[/]", maxValue: 1)
        );

        var deleteTasks = matches.Select(async rg =>
        {
            await gate.WaitAsync();
            try
            {
                rgTasks[rg.Data.Name].Increment(0.5); // show started
                await rg.DeleteAsync(Azure.WaitUntil.Completed);
                rgTasks[rg.Data.Name].Value = 1;
            }
            finally
            {
                gate.Release();
                overallTask.Increment(1);
            }
        });

        await Task.WhenAll(deleteTasks);
    });

AnsiConsole.MarkupLine("[bold green]✅ Cleanup completed.[/]");

// Print what was deleted
AnsiConsole.MarkupLine("[bold]Deleted resource groups:[/]");
foreach (var rg in matches)
    AnsiConsole.MarkupLine($"  [yellow]{rg.Data.Name}[/]");

Hmm, this does work, but it seems kind of dangerous. There's no filtering, there's no "dry run". What happens when I select an RG that is in use and shouldn't be deleted?

Added a fork with some improvements

There's no filtering because you literally have to select the rg to delete 😄