Add room database retrieval and validation

osu.Server.Spectator.Tests/MultiplayerFlowTests.cs

@@ -510,6 +510,19 @@ public TestMultiplayerHub(MemoryDistributedCache cache)
             {
             }
 
+            protected override Task UpdateDatabaseParticipants(MultiplayerRoom room) => Task.CompletedTask;
+            protected override Task UpdateDatabaseSettings(MultiplayerRoom room) => Task.CompletedTask;
+            protected override Task EndDatabaseMatch(MultiplayerRoom room) => Task.CompletedTask;
+
+            protected override Task<MultiplayerRoom> RetrieveRoom(long roomId)
+            {
+                // bypass database for testing.
+                return Task.FromResult(new MultiplayerRoom(roomId)
+                {
+                    Host = new MultiplayerRoomUser(CurrentContextUserId)
+                });
+            }
+
             public new bool TryGetRoom(long roomId, [MaybeNullWhen(false)] out MultiplayerRoom room)
                 => base.TryGetRoom(roomId, out room);
         }

osu.Server.Spectator.sln.DotSettings

@@ -128,6 +128,7 @@
 	<s:String x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=PossibleMultipleEnumeration/@EntryIndexedValue">HINT</s:String>
 	<s:String x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=PrivateVariableCanBeMadeReadonly/@EntryIndexedValue">WARNING</s:String>
 	<s:String x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=PublicConstructorInAbstractClass/@EntryIndexedValue">WARNING</s:String>
+	<s:String x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=RedundantAnonymousTypePropertyName/@EntryIndexedValue">HINT</s:String>
 	<s:String x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=RedundantArgumentDefaultValue/@EntryIndexedValue">HINT</s:String>
 	<s:String x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=RedundantArrayCreationExpression/@EntryIndexedValue">WARNING</s:String>
 	<s:String x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=RedundantAttributeParentheses/@EntryIndexedValue">WARNING</s:String>

osu.Server.Spectator/Database.cs

@@ -0,0 +1,21 @@
+// 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 System;
+using MySqlConnector;
+
+namespace osu.Server.Spectator
+{
+    public class Database
+    {
+        public static MySqlConnection GetConnection()
+        {
+            string host = (Environment.GetEnvironmentVariable("DB_HOST") ?? "localhost");
+            string user = (Environment.GetEnvironmentVariable("DB_USER") ?? "root");
+
+            var connection = new MySqlConnection($"Server={host};Database=osu;User ID={user};ConnectionTimeout=5;ConnectionReset=false;Pooling=true;");
+            connection.Open();
+            return connection;
+        }
+    }
+}

osu.Server.Spectator/DatabaseModels/multiplayer_playlist_item.cs

@@ -0,0 +1,44 @@
+// 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 System;
+using Newtonsoft.Json;
+using osu.Game.Online.RealtimeMultiplayer;
+
+// ReSharper disable InconsistentNaming (matches database table)
+
+namespace osu.Server.Spectator.DatabaseModels
+{
+    [Serializable]
+    public class multiplayer_playlist_item
+    {
+        public long id { get; set; }
+        public long room_id { get; set; }
+        public int beatmap_id { get; set; }
+        public short ruleset_id { get; set; }
+        public short? playlist_order { get; set; }
+        public string? allowed_mods { get; set; }
+        public string? required_mods { get; set; }
+        public DateTimeOffset? created_at { get; set; }
+        public DateTimeOffset? updated_at { get; set; }
+
+        // for deserialization
+        public multiplayer_playlist_item()
+        {
+        }
+
+        /// <summary>
+        /// Create a playlist item model from the latest settings in a room.
+        /// </summary>
+        /// <param name="room">The room to retrieve settings from.</param>
+        public multiplayer_playlist_item(MultiplayerRoom room)
+        {
+            room_id = room.RoomID;
+
+            beatmap_id = room.Settings.BeatmapID;
+            ruleset_id = (short)room.Settings.RulesetID;
+            required_mods = JsonConvert.SerializeObject(room.Settings.Mods);
+            updated_at = DateTimeOffset.Now;
+        }
+    }
+}

osu.Server.Spectator/DatabaseModels/multiplayer_room.cs

@@ -0,0 +1,27 @@
+// 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 System;
+using osu.Game.Online.Multiplayer;
+
+// ReSharper disable InconsistentNaming (matches database table)
+
+namespace osu.Server.Spectator.DatabaseModels
+{
+    [Serializable]
+    public class multiplayer_room
+    {
+        public long id { get; set; }
+        public int user_id { get; set; }
+        public string name { get; set; } = string.Empty;
+        public int channel_id { get; set; }
+        public DateTimeOffset starts_at { get; set; }
+        public DateTimeOffset? ends_at { get; set; }
+        public byte max_attempts { get; set; }
+        public int participant_count { get; set; }
+        public DateTimeOffset? created_at { get; set; }
+        public DateTimeOffset? updated_at { get; set; }
+        public DateTimeOffset? deleted_at { get; set; }
+        public RoomCategory category { get; set; }
+    }
+}

osu.Server.Spectator/Hubs/MultiplayerHub.cs

@@ -8,8 +8,12 @@
 using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Threading.Tasks;
+using Dapper;
 using Microsoft.Extensions.Caching.Distributed;
+using Newtonsoft.Json;
+using osu.Game.Online.API;
 using osu.Game.Online.RealtimeMultiplayer;
+using osu.Server.Spectator.DatabaseModels;
 
 namespace osu.Server.Spectator.Hubs
 {
@@ -52,45 +56,82 @@ public async Task<MultiplayerRoom> JoinRoom(long roomId)
             if (state != null)
             {
                 // if the user already has a state, it means they are already in a room and can't join another without first leaving.
-                throw new InvalidStateException("Can't join a room when already in another room");
+                throw new InvalidStateException("Can't join a room when already in another room.");
             }
 
-            MultiplayerRoom? room;
-
-            bool shouldBecomeHost = false;
+            // add the user to the room.
+            var roomUser = new MultiplayerRoomUser(CurrentContextUserId);
 
-            lock (active_rooms)
+            // check whether we are already aware of this match.
+            if (!TryGetRoom(roomId, out var room))
             {
-                // check whether we are already aware of this match.
+                room = await RetrieveRoom(roomId);
+
+                room.Host = roomUser;
 
-                if (!TryGetRoom(roomId, out room))
+                lock (active_rooms)
                 {
-                    // TODO: get details of the room from the database. hard abort if non existent.
                     Console.WriteLine($"Tracking new room {roomId}.");
-                    active_rooms.Add(roomId, room = new MultiplayerRoom(roomId));
-                    shouldBecomeHost = true;
+                    active_rooms.Add(roomId, room);
                 }
             }
 
-            // add the user to the room.
-            var roomUser = new MultiplayerRoomUser(CurrentContextUserId);
-
             using (room.LockForUpdate())
             {
                 room.Users.Add(roomUser);
-
-                if (shouldBecomeHost)
-                    room.Host = roomUser;
-
                 await Clients.Group(GetGroupId(roomId)).UserJoined(roomUser);
                 await Groups.AddToGroupAsync(Context.ConnectionId, GetGroupId(roomId));
+
+                await UpdateDatabaseParticipants(room);
             }
 
             await UpdateLocalUserState(new MultiplayerClientState(roomId));
 
             return room;
         }
 
+        /// <summary>
+        /// Attempt to construct and a room based on a room ID specification.
+        /// This will check the database backing to ensure things are in a consistent state.
+        /// </summary>
+        /// <param name="roomId">The proposed room ID.</param>
+        /// <exception cref="InvalidStateException">If anything is wrong with this request.</exception>
+        protected virtual async Task<MultiplayerRoom> RetrieveRoom(long roomId)
+        {
+            using (var conn = Database.GetConnection())
+            {
+                var databaseRoom = await conn.QueryFirstOrDefaultAsync<multiplayer_room>("SELECT * FROM multiplayer_rooms WHERE category = 'realtime' AND id = @RoomID", new
+                {
+                    RoomID = roomId
+                });
+
+                if (databaseRoom == null)
+                    throw new InvalidStateException("Specified match does not exist.");
+
+                if (databaseRoom.ends_at != null)
+                    throw new InvalidStateException("Match has already ended.");
+
+                if (databaseRoom.user_id != CurrentContextUserId)
+                    throw new InvalidStateException("Non-host is attempting to join match before host");
+
+                var playlistItem = await conn.QuerySingleAsync<multiplayer_playlist_item>("SELECT * FROM multiplayer_playlist_items WHERE room_id = @RoomID", new
+                {
+                    RoomID = roomId
+                });
+
+                return new MultiplayerRoom(roomId)
+                {
+                    Settings = new MultiplayerRoomSettings
+                    {
+                        BeatmapID = playlistItem.beatmap_id,
+                        RulesetID = playlistItem.ruleset_id,
+                        Name = databaseRoom.name,
+                        Mods = playlistItem.allowed_mods != null ? JsonConvert.DeserializeObject<IEnumerable<APIMod>>(playlistItem.allowed_mods) : Array.Empty<APIMod>()
+                    }
+                };
+            }
+        }
+
         public async Task LeaveRoom()
         {
             var room = await getLocalUserRoom();
@@ -109,6 +150,8 @@ public async Task LeaveRoom()
 
                 room.Users.Remove(user);
 
+                await UpdateDatabaseParticipants(room);
+
                 if (room.Users.Count == 0)
                 {
                     lock (active_rooms)
@@ -117,6 +160,8 @@ public async Task LeaveRoom()
                         active_rooms.Remove(room.RoomID);
                     }
 
+                    await EndDatabaseMatch(room);
+
                     return;
                 }
 
@@ -231,6 +276,9 @@ public async Task ChangeSettings(MultiplayerRoomSettings settings)
                 ensureIsHost(room);
 
                 room.Settings = settings;
+
+                await UpdateDatabaseSettings(room);
+
                 await Clients.Group(GetGroupId(room.RoomID)).SettingsChanged(settings);
             }
         }
@@ -250,6 +298,65 @@ protected override Task OnDisconnectedAsync(Exception exception, MultiplayerClie
         /// <param name="gameplay">Whether the group ID should be for active gameplay, or room control messages.</param>
         public static string GetGroupId(long roomId, bool gameplay = false) => $"room:{roomId}:{gameplay}";
 
+        protected virtual async Task UpdateDatabaseSettings(MultiplayerRoom room)
+        {
+            using (var conn = Database.GetConnection())
+            {
+                var dbPlaylistItem = new multiplayer_playlist_item(room);
+
+                await conn.ExecuteAsync("UPDATE multiplayer_rooms SET name = @Name WHERE id = @RoomID", new
+                {
+                    RoomID = room.RoomID,
+                    Name = room.Settings.Name
+                });
+
+                await conn.ExecuteAsync("UPDATE multiplayer_playlist_items SET beatmap_id = @beatmap_id, ruleset_id = @ruleset_id, required_mods = @required_mods, updated_at = NOW() WHERE room_id = @room_id", dbPlaylistItem);
+            }
+        }
+
+        protected virtual async Task EndDatabaseMatch(MultiplayerRoom room)
+        {
+            using (var conn = Database.GetConnection())
+            {
+                await conn.ExecuteAsync("UPDATE multiplayer_rooms SET ends_at = NOW() WHERE id = @RoomID", new
+                {
+                    RoomID = room.RoomID
+                });
+            }
+        }
+
+        protected virtual async Task UpdateDatabaseParticipants(MultiplayerRoom room)
+        {
+            using (var conn = Database.GetConnection())
+            {
+                using (var transaction = await conn.BeginTransactionAsync())
+                {
+                    // This should be considered *very* temporary, and for display purposes only!
+                    await conn.ExecuteAsync("DELETE FROM multiplayer_rooms_high WHERE room_id = @RoomID", new
+                    {
+                        RoomID = room.RoomID
+                    }, transaction);
+
+                    foreach (var u in room.Users)
+                    {
+                        await conn.ExecuteAsync("INSERT INTO multiplayer_rooms_high (room_id, user_id) VALUES (@RoomID, @UserID)", new
+                        {
+                            RoomID = room.RoomID,
+                            UserID = u.UserID
+                        }, transaction);
+                    }
+
+                    await transaction.CommitAsync();
+                }
+
+                await conn.ExecuteAsync("UPDATE multiplayer_rooms SET participant_count = @Count WHERE id = @RoomID", new
+                {
+                    RoomID = room.RoomID,
+                    Count = room.Users.Count
+                });
+            }
+        }
+
         /// <summary>
         /// Should be called when user states change, to check whether the new overall room state can trigger a room-level state change.
         /// </summary>

osu.Server.Spectator/Program.cs

@@ -1,25 +1,13 @@
 // 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 System;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.Extensions.Hosting;
-using MySqlConnector;
 
 namespace osu.Server.Spectator
 {
     public static class Program
     {
-        public static MySqlConnection GetDatabaseConnection()
-        {
-            string host = (Environment.GetEnvironmentVariable("DB_HOST") ?? "localhost");
-            string user = (Environment.GetEnvironmentVariable("DB_USER") ?? "root");
-
-            var connection = new MySqlConnection($"Server={host};Database=osu;User ID={user};ConnectionTimeout=1;ConnectionReset=false;Pooling=true;");
-            connection.Open();
-            return connection;
-        }
-
         public static void Main(string[] args)
         {
             createHostBuilder(args).Build().Run();