feat(bot): store command message info in redis

PluralKit.Bot/CommandSystem/Context/Context.cs

@@ -94,12 +94,12 @@ public class Context
             AllowedMentions = mentions ?? new AllowedMentions()
         });
 
-        if (embed != null)
+        // if (embed != null)
-        {
+        // {
             // Sensitive information that might want to be deleted by :x: reaction is typically in an embed format (member cards, for example)
-            // This may need to be changed at some point but works well enough for now
+            // but since we can, we just store all sent messages for possible deletion
             await _commandMessageService.RegisterMessage(msg.Id, msg.ChannelId, Author.Id);
-        }
+        // }
 
         return msg;
     }

PluralKit.Bot/Commands/Message.cs

@@ -2,6 +2,8 @@
 using System.Text;
 using System.Text.RegularExpressions;
 
+using Autofac;
+
 using Myriad.Builders;
 using Myriad.Cache;
 using Myriad.Extensions;
@@ -304,14 +306,14 @@ public class ProxiedMessage
 
     private async Task DeleteCommandMessage(Context ctx, ulong messageId)
     {
-        var message = await ctx.Repository.GetCommandMessage(messageId);
+        var (authorId, channelId) = await ctx.Services.Resolve<CommandMessageService>().GetCommandMessage(messageId);
-        if (message == null)
+        if (authorId == null)
             throw Errors.MessageNotFound(messageId);
 
-        if (message.AuthorId != ctx.Author.Id)
+        if (authorId != ctx.Author.Id)
             throw new PKError("You can only delete command messages queried by this account.");
 
-        await ctx.Rest.DeleteMessage(message.ChannelId, message.MessageId);
+        await ctx.Rest.DeleteMessage(channelId!.Value, messageId);
 
         if (ctx.Guild != null)
             await ctx.Rest.DeleteMessage(ctx.Message);

PluralKit.Bot/Handlers/ReactionAdded.cs

@@ -73,10 +73,10 @@ public class ReactionAdded: IEventHandler<MessageReactionAddEvent>
                 return;
             }
 
-            var commandMsg = await _commandMessageService.GetCommandMessage(evt.MessageId);
+            var (authorId, _) = await _commandMessageService.GetCommandMessage(evt.MessageId);
-            if (commandMsg != null)
+            if (authorId != null)
             {
-                await HandleCommandDeleteReaction(evt, commandMsg);
+                await HandleCommandDeleteReaction(evt, authorId.Value);
                 return;
             }
         }
@@ -141,11 +141,11 @@ public class ReactionAdded: IEventHandler<MessageReactionAddEvent>
         await _repo.DeleteMessage(evt.MessageId);
     }
 
-    private async ValueTask HandleCommandDeleteReaction(MessageReactionAddEvent evt, CommandMessage? msg)
+    private async ValueTask HandleCommandDeleteReaction(MessageReactionAddEvent evt, ulong? authorId)
     {
         // Can only delete your own message
         // (except in DMs, where msg will be null)
-        if (msg != null && msg.AuthorId != evt.UserId)
+        if (authorId != null && authorId != evt.UserId)
             return;
 
         // todo: don't try to delete the user's own messages in DMs

PluralKit.Bot/Services/CommandMessageService.cs

@@ -8,16 +8,13 @@ namespace PluralKit.Bot;
 
 public class CommandMessageService
 {
-    private readonly IClock _clock;
+    private readonly RedisService _redis;
-    private readonly IDatabase _db;
     private readonly ILogger _logger;
-    private readonly ModelRepository _repo;
+    private static readonly TimeSpan CommandMessageRetention = TimeSpan.FromHours(24);
 
-    public CommandMessageService(IDatabase db, ModelRepository repo, IClock clock, ILogger logger)
+    public CommandMessageService(RedisService redis, IClock clock, ILogger logger)
     {
-        _db = db;
+        _redis = redis;
-        _repo = repo;
-        _clock = clock;
         _logger = logger.ForContext<CommandMessageService>();
     }
 
@@ -27,9 +24,18 @@ public class CommandMessageService
             "Registering command response {MessageId} from author {AuthorId} in {ChannelId}",
             messageId, authorId, channelId
         );
-        await _repo.SaveCommandMessage(messageId, channelId, authorId);
+
+        await _redis.Connection.GetDatabase().StringSetAsync(messageId.ToString(), $"{authorId}-{channelId}", expiry: CommandMessageRetention);
     }
 
-    public async Task<CommandMessage?> GetCommandMessage(ulong messageId) =>
+    public async Task<(ulong?, ulong?)> GetCommandMessage(ulong messageId)
-        await _repo.GetCommandMessage(messageId);
+    {
+        var str = await _redis.Connection.GetDatabase().StringGetAsync(messageId.ToString());
+        if (str.HasValue)
+        {
+            var split = ((string)str).Split("-");
+            return (ulong.Parse(split[0]), ulong.Parse(split[1]));
+        }
+        return (null, null);
+    }
 }

PluralKit.Core/Database/Repository/ModelRepository.CommandMessage.cs

@@ -1,36 +0,0 @@
-using SqlKata;
-
-namespace PluralKit.Core;
-
-public partial class ModelRepository
-{
-    public Task SaveCommandMessage(ulong messageId, ulong channelId, ulong authorId)
-    {
-        var query = new Query("command_messages").AsInsert(new
-        {
-            message_id = messageId,
-            channel_id = channelId,
-            author_id = authorId,
-        });
-        return _db.ExecuteQuery(query);
-    }
-
-    public Task<CommandMessage?> GetCommandMessage(ulong messageId)
-    {
-        var query = new Query("command_messages").Where("message_id", messageId);
-        return _db.QueryFirst<CommandMessage?>(query);
-    }
-
-    public Task<int> DeleteCommandMessagesBefore(ulong messageIdThreshold)
-    {
-        var query = new Query("command_messages").AsDelete().Where("message_id", "<", messageIdThreshold);
-        return _db.QueryFirst<int>(query);
-    }
-}
-
-public class CommandMessage
-{
-    public ulong AuthorId { get; set; }
-    public ulong MessageId { get; set; }
-    public ulong ChannelId { get; set; }
-}

PluralKit.ScheduledTasks/TaskHandler.cs

@@ -19,7 +19,6 @@ namespace PluralKit.ScheduledTasks;
 
 public class TaskHandler
 {
-    private static readonly Duration CommandMessageRetention = Duration.FromHours(24);
     private readonly IDatabase _db;
     private readonly RedisService _redis;
     private readonly bool _useRedisMetrics;
@@ -65,9 +64,6 @@ public class TaskHandler
         if (_useRedisMetrics)
             await CollectBotStats();
 
-        // Clean up message cache in postgres
-        await CleanupOldMessages();
-
         stopwatch.Stop();
         _logger.Information("Ran scheduled tasks in {Time}", stopwatch.ElapsedDuration());
     }
@@ -108,18 +104,6 @@ public class TaskHandler
         _logger.Debug("Submitted metrics to backend");
     }
 
-    private async Task CleanupOldMessages()
-    {
-        var deleteThresholdInstant = SystemClock.Instance.GetCurrentInstant() - CommandMessageRetention;
-        var deleteThresholdSnowflake = InstantToSnowflake(deleteThresholdInstant);
-
-        var deletedRows = await _repo.DeleteCommandMessagesBefore(deleteThresholdSnowflake);
-
-        _logger.Information(
-            "Pruned {DeletedRows} command messages older than retention {Retention} (older than {DeleteThresholdInstant} / {DeleteThresholdSnowflake})",
-            deletedRows, CommandMessageRetention, deleteThresholdInstant, deleteThresholdSnowflake);
-    }
-
     // we don't have access to PluralKit.Bot here, so this needs to be vendored
     public static ulong InstantToSnowflake(Instant time) =>
         (ulong)(time - Instant.FromUtc(2015, 1, 1, 0, 0, 0)).TotalMilliseconds << 22;