Change IBeatmapMetadataInfo.Author to be an IUser

osu.Game/Beatmaps/IBeatmapMetadataInfo.cs

@@ -2,6 +2,7 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using osu.Game.Users;
 
 #nullable enable
 
@@ -35,7 +36,7 @@ namespace osu.Game.Beatmaps
         /// <summary>
         /// The author of this beatmap.
         /// </summary>
-        string Author { get; } // eventually should be linked to a persisted User.
+        IUser Author { get; }
 
         /// <summary>
         /// The source of this beatmap.

osu.Game/Models/RealmBeatmapMetadata.cs

@@ -5,6 +5,7 @@ using System;
 using Newtonsoft.Json;
 using osu.Framework.Testing;
 using osu.Game.Beatmaps;
+using osu.Game.Users;
 using Realms;
 
 #nullable enable
@@ -26,7 +27,7 @@ namespace osu.Game.Models
         [JsonProperty("artist_unicode")]
         public string ArtistUnicode { get; set; } = string.Empty;
 
-        public string Author { get; set; } = string.Empty; // eventually should be linked to a persisted User.
+        public RealmUser Author { get; set; } = new RealmUser();
 
         public string Source { get; set; } = string.Empty;
 
@@ -41,5 +42,7 @@ namespace osu.Game.Models
 
         public string AudioFile { get; set; } = string.Empty;
         public string BackgroundFile { get; set; } = string.Empty;
+
+        IUser IBeatmapMetadataInfo.Author => Author;
     }
 }

osu.Game/Models/RealmUser.cs

@@ -0,0 +1,15 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Game.Users;
+using Realms;
+
+namespace osu.Game.Models
+{
+    public class RealmUser : EmbeddedObject, IUser
+    {
+        public int OnlineID { get; set; } = 1;
+
+        public string Username { get; set; }
+    }
+}