Various small fixes, setting guild config now works

PluralKit.Core/Database/Database.cs

@@ -1,8 +1,13 @@
 using System;
+using System.Data;
 using System.Threading.Tasks;
 
 using App.Metrics;
 
+using Dapper;
+
+using NodaTime;
+
 using Npgsql;
 
 using Serilog;
@@ -24,6 +29,29 @@ namespace PluralKit.Core
             _metrics = metrics;
             _logger = logger;
         }
+        
+        public static void InitStatic()
+        {
+            // Dapper by default tries to pass ulongs to Npgsql, which rejects them since PostgreSQL technically
+            // doesn't support unsigned types on its own.
+            // Instead we add a custom mapper to encode them as signed integers instead, converting them back and forth.
+            SqlMapper.RemoveTypeMap(typeof(ulong));
+            SqlMapper.AddTypeHandler(new UlongEncodeAsLongHandler());
+            SqlMapper.AddTypeHandler(new UlongArrayHandler());
+            DefaultTypeMap.MatchNamesWithUnderscores = true;
+
+            NpgsqlConnection.GlobalTypeMapper.UseNodaTime();
+            // With the thing we add above, Npgsql already handles NodaTime integration
+            // This makes Dapper confused since it thinks it has to convert it anyway and doesn't understand the types
+            // So we add a custom type handler that literally just passes the type through to Npgsql
+            SqlMapper.AddTypeHandler(new PassthroughTypeHandler<Instant>());
+            SqlMapper.AddTypeHandler(new PassthroughTypeHandler<LocalDate>());
+            
+            // Register our custom types to Npgsql
+            // Without these it'll still *work* but break at the first launch + probably cause other small issues
+            NpgsqlConnection.GlobalTypeMapper.MapComposite<ProxyTag>("proxy_tag");
+            NpgsqlConnection.GlobalTypeMapper.MapEnum<PrivacyLevel>("privacy_level");
+        }
 
         public async Task<IPKConnection> Obtain()
         {
@@ -48,5 +76,27 @@ namespace PluralKit.Core
             await using var conn = await Obtain();
             return await func(conn);
         }
+
+        private class PassthroughTypeHandler<T>: SqlMapper.TypeHandler<T>
+        {
+            public override void SetValue(IDbDataParameter parameter, T value) => parameter.Value = value;
+            public override T Parse(object value) => (T) value;
+        }
+
+        private class UlongEncodeAsLongHandler: SqlMapper.TypeHandler<ulong>
+        {
+            public override ulong Parse(object value) =>
+                // Cast to long to unbox, then to ulong (???)
+                (ulong) (long) value;
+
+            public override void SetValue(IDbDataParameter parameter, ulong value) => parameter.Value = (long) value;
+        }
+
+        private class UlongArrayHandler: SqlMapper.TypeHandler<ulong[]>
+        {
+            public override void SetValue(IDbDataParameter parameter, ulong[] value) => parameter.Value = Array.ConvertAll(value, i => (long) i);
+
+            public override ulong[] Parse(object value) => Array.ConvertAll((long[]) value, i => (ulong) i);
+        }
     }
 }

PluralKit.Core/Database/Schemas.cs

@@ -25,13 +25,6 @@ namespace PluralKit.Core
             _logger = logger.ForContext<Schemas>();
         }
 
-        public static void Initialize()
-        {
-            // Without these it'll still *work* but break at the first launch + probably cause other small issues
-            NpgsqlConnection.GlobalTypeMapper.MapComposite<ProxyTag>("proxy_tag");
-            NpgsqlConnection.GlobalTypeMapper.MapEnum<PrivacyLevel>("privacy_level");
-        }
-
         public async Task InitializeDatabase()
         {
             // Run everything in a transaction