add: Added .cleanupguilddata command which will delete all guildconfigs, xp stats and other data related to any guild the bot is no longer in. This is a highly destructive and irreversible command.

dev: Added cascade deletes to any tables which have guildconfigs FK, as well as to some other missing places

src/NadekoBot/Modules/Administration/DangerousCommands/CleanupCommands.cs

@@ -0,0 +1,31 @@
+namespace NadekoBot.Modules.Administration.DangerousCommands;
+
+public partial class Administration 
+{
+    [Group]
+    public class CleanupCommands : CleanupModuleBase
+    {
+        private readonly ICleanupService _svc;
+
+        public CleanupCommands(ICleanupService svc)
+            => _svc = svc;
+
+        [Cmd]
+        [OwnerOnly]
+        [RequireContext(ContextType.DM)]
+        public async Task CleanupGuildData()
+        {
+            var result = await _svc.DeleteMissingGuildDataAsync();
+
+            if (result is null)
+            {
+                await ctx.ErrorAsync();
+                return;
+            }
+
+            await Response()
+                  .Confirm($"{result.GuildCount} guilds' data remain in the database.")
+                  .SendAsync();
+        }
+    }
+}

src/NadekoBot/Modules/Administration/DangerousCommands/CleanupService.cs

@@ -0,0 +1,106 @@
+using LinqToDB;
+using LinqToDB.Data;
+using LinqToDB.EntityFrameworkCore;
+using NadekoBot.Common.ModuleBehaviors;
+using NadekoBot.Db.Models;
+
+namespace NadekoBot.Modules.Administration.DangerousCommands;
+
+public sealed class CleanupService : ICleanupService, IReadyExecutor, INService
+{
+    private readonly IPubSub _pubSub;
+    private TypedKey<KeepReport> _keepReportKey = new("cleanup:report");
+    private TypedKey<bool> _keepTriggerKey = new("cleanup:trigger");
+    private readonly DiscordSocketClient _client;
+    private ConcurrentDictionary<int, ulong[]> guildIds;
+    private readonly IBotCredsProvider _creds;
+    private readonly DbService _db;
+
+    public CleanupService(
+        IPubSub pubSub,
+        DiscordSocketClient client,
+        IBotCredsProvider creds,
+        DbService db)
+    {
+        _pubSub = pubSub;
+        _client = client;
+        _creds = creds;
+        _db = db;
+    }
+
+    public async Task<KeepResult?> DeleteMissingGuildDataAsync()
+    {
+        guildIds = new();
+        var totalShards = _creds.GetCreds().TotalShards;
+        await _pubSub.Pub(_keepTriggerKey, true);
+        var counter = 0;
+        while (guildIds.Keys.Count < totalShards)
+        {
+            await Task.Delay(1000);
+            counter++;
+
+            if (counter >= 5)
+                break;
+        }
+
+        if (guildIds.Keys.Count < totalShards)
+            return default;
+
+        var allIds = guildIds.SelectMany(x => x.Value)
+                             .ToArray();
+
+        await using var ctx = _db.GetDbContext();
+        await using var linqCtx = ctx.CreateLinqToDBContext();
+        await using var tempTable = linqCtx.CreateTempTable<CleanupId>();
+
+        foreach (var chunk in allIds.Chunk(20000))
+        {
+            await tempTable.BulkCopyAsync(chunk.Select(x => new CleanupId()
+            {
+                GuildId = x
+            }));
+        }
+
+        await ctx.GetTable<GuildConfig>()
+                 .Where(x => !tempTable.Select(x => x.GuildId)
+                                       .Contains(x.GuildId))
+                 .DeleteAsync();
+
+
+        await ctx.GetTable<UserXpStats>()
+                 .Where(x => !tempTable.Select(x => x.GuildId)
+                                       .Contains(x.GuildId))
+                 .DeleteAsync();
+
+        return new()
+        {
+            GuildCount = guildIds.Keys.Count,
+        };
+    }
+    
+    private ValueTask OnKeepReport(KeepReport report)
+    {
+        guildIds[report.ShardId] = report.GuildIds;
+        return default;
+    }
+
+    public async Task OnReadyAsync()
+    {
+        await _pubSub.Sub(_keepTriggerKey, OnKeepTrigger);
+
+        if (_client.ShardId == 0)
+            await _pubSub.Sub(_keepReportKey, OnKeepReport);
+    }
+
+    private ValueTask OnKeepTrigger(bool arg)
+    {
+        _pubSub.Pub(_keepReportKey,
+            new KeepReport()
+            {
+                ShardId = _client.ShardId,
+                GuildIds = _client.GetGuildIds(),
+            });
+
+        return default;
+    }
+}

src/NadekoBot/Modules/Administration/DangerousCommands/_common/CleanupId.cs

@@ -0,0 +1,9 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace NadekoBot.Modules.Administration.DangerousCommands;
+
+public sealed class CleanupId
+{
+    [Key]
+    public ulong GuildId { get; set; }
+}

src/NadekoBot/Modules/Administration/DangerousCommands/_common/ICleanupService.cs

@@ -0,0 +1,6 @@
+namespace NadekoBot.Modules.Administration.DangerousCommands;
+
+public interface ICleanupService
+{
+    Task<KeepResult?> DeleteMissingGuildDataAsync();
+}

src/NadekoBot/Modules/Administration/DangerousCommands/_common/KeepReport.cs

@@ -0,0 +1,7 @@
+namespace NadekoBot.Modules.Administration.DangerousCommands;
+
+public sealed class KeepReport
+{
+    public required int ShardId { get; init; }
+    public required ulong[] GuildIds { get; init; }
+}

src/NadekoBot/Modules/Administration/DangerousCommands/_common/KeepResult.cs

@@ -0,0 +1,6 @@
+namespace NadekoBot.Modules.Administration.DangerousCommands;
+
+public sealed class KeepResult
+{
+    public required int GuildCount { get; init; }
+}