feat: import/export settings, send backup of settings when leaving guild

Catalogger.Backend/Api/GuildsController.Backup.cs

@@ -0,0 +1,117 @@
+// Copyright (C) 2021-present sam (starshines.gay)
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published
+// by the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+using System.Net;
+using Catalogger.Backend.Api.Middleware;
+using Catalogger.Backend.Database.Models;
+using Microsoft.AspNetCore.Mvc;
+using NodaTime;
+using Remora.Discord.API;
+
+namespace Catalogger.Backend.Api;
+
+public partial class GuildsController
+{
+    [Authorize]
+    [HttpGet("config")]
+    public async Task<IActionResult> ExportConfigAsync(string id)
+    {
+        var (guildId, _) = await ParseGuildAsync(id);
+        var guildConfig = await guildRepository.GetAsync(guildId);
+
+        return Ok(await ToExport(guildConfig));
+    }
+
+    [Authorize]
+    [HttpPost("config")]
+    public async Task<IActionResult> ImportConfigAsync(
+        string id,
+        [FromBody] GuildConfigExport export
+    )
+    {
+        var (guildId, _) = await ParseGuildAsync(id);
+        if (export.Id != guildId.Value)
+            throw new ApiError(
+                HttpStatusCode.BadRequest,
+                ErrorCode.BadRequest,
+                "This backup is not from this server."
+            );
+
+        // Filter invites to *only* those that exist for this guild.
+        // Blame past me for not making (code, guild_id) a unique index >:|
+        var cachedInvites = (await inviteCache.TryGetAsync(guildId)).ToList();
+        var invites = export.Invites.Where(i => cachedInvites.Any(ci => i.Code == ci.Code));
+
+        await guildRepository.ImportConfigAsync(
+            guildId.Value,
+            export.Channels,
+            export.BannedSystems,
+            export.KeyRoles
+        );
+
+        await inviteRepository.ImportInvitesAsync(
+            guildId,
+            invites.Select(i => new Invite
+            {
+                Code = i.Code,
+                Name = i.Name,
+                GuildId = guildId.Value,
+            })
+        );
+
+        await watchlistRepository.ImportWatchlistAsync(
+            guildId,
+            export.Watchlist.Select(w => new Watchlist
+            {
+                GuildId = guildId.Value,
+                UserId = w.UserId,
+                ModeratorId = w.ModeratorId,
+                AddedAt = w.AddedAt,
+                Reason = w.Reason,
+            })
+        );
+
+        return NoContent();
+    }
+
+    private async Task<GuildConfigExport> ToExport(Database.Models.Guild config)
+    {
+        var id = DiscordSnowflake.New(config.Id);
+        var invites = await inviteRepository.GetGuildInvitesAsync(id);
+        var watchlist = await watchlistRepository.GetGuildWatchlistAsync(id);
+
+        return new GuildConfigExport(
+            config.Id,
+            config.Channels,
+            config.BannedSystems,
+            config.KeyRoles,
+            invites.Select(i => new InviteExport(i.Code, i.Name)),
+            watchlist.Select(w => new WatchlistExport(w.UserId, w.AddedAt, w.ModeratorId, w.Reason))
+        );
+    }
+
+    public record GuildConfigExport(
+        ulong Id,
+        Database.Models.Guild.ChannelConfig Channels,
+        string[] BannedSystems,
+        ulong[] KeyRoles,
+        IEnumerable<InviteExport> Invites,
+        IEnumerable<WatchlistExport> Watchlist
+    );
+
+    public record InviteExport(string Code, string Name);
+
+    public record WatchlistExport(ulong UserId, Instant AddedAt, ulong ModeratorId, string Reason);
+}

Catalogger.Backend/Api/GuildsController.Remove.cs

@@ -14,12 +14,15 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 using System.Net;
+using System.Text;
+using System.Text.Json;
 using Catalogger.Backend.Api.Middleware;
 using Catalogger.Backend.Bot;
 using Catalogger.Backend.Extensions;
 using Catalogger.Backend.Services;
 using Dapper;
 using Microsoft.AspNetCore.Mvc;
+using Remora.Discord.API.Abstractions.Rest;
 using Remora.Discord.Extensions.Embeds;
 
 namespace Catalogger.Backend.Api;
@@ -40,6 +43,8 @@ public partial class GuildsController
         }
 
         var guildConfig = await guildRepository.GetAsync(guildId);
+        var export = await ToExport(guildConfig);
+
         var logChannelId =
             webhookExecutor.GetLogChannel(guildConfig, LogChannelType.GuildUpdate)
             ?? webhookExecutor.GetLogChannel(guildConfig, LogChannelType.GuildMemberRemove);
@@ -50,15 +55,25 @@ public partial class GuildsController
             var embed = new EmbedBuilder()
                 .WithTitle("Catalogger is leaving this server")
                 .WithDescription(
-                    $"A moderator in this server ({currentUser.Tag}, <@{currentUser.Id}>) requested that Catalogger leave. "
-                        + "All data related to this server will be deleted."
+                    $"""
+                    A moderator in this server ({currentUser.Tag}, <@{currentUser.Id}>) requested that Catalogger leave.
+                    All data related to this server will be deleted.
+
+                    A backup of this server's configuration is attached to this message,
+                    in case you want to use the bot again later.
+                    """
                 )
                 .WithColour(DiscordUtils.Red)
                 .WithCurrentTimestamp()
                 .Build()
                 .GetOrThrow();
 
-            await webhookExecutor.SendLogAsync(logChannelId.Value, [embed], []);
+            var exportData = JsonSerializer.Serialize(export, JsonUtils.ApiJsonOptions);
+            var file = new FileData(
+                "config-backup.json",
+                new MemoryStream(Encoding.UTF8.GetBytes(exportData))
+            );
+            await webhookExecutor.SendLogAsync(logChannelId.Value, [embed], [file]);
         }
         else
         {
@@ -125,7 +140,7 @@ public partial class GuildsController
 
         _logger.Information("Left guild {GuildId} and removed all data for it", guildId);
 
-        return NoContent();
+        return Ok(export);
     }
 
     public record LeaveGuildRequest(string Name);

Catalogger.Backend/Api/GuildsController.cs

@@ -34,6 +34,8 @@ public partial class GuildsController(
     ILogger logger,
     DatabaseConnection dbConn,
     GuildRepository guildRepository,
+    InviteRepository inviteRepository,
+    WatchlistRepository watchlistRepository,
     GuildCache guildCache,
     EmojiCache emojiCache,
     ChannelCache channelCache,