Merge pull request #16590 from peppy/realm-migrate-on-failure

Allow realm migration to run again if interrupted halfway

osu.Game/Database/EFToRealmMigrator.cs

@@ -27,7 +27,9 @@ namespace osu.Game.Database
 {
     internal class EFToRealmMigrator : CompositeDrawable
     {
-        public bool FinishedMigrating { get; private set; }
+        public Task<bool> MigrationCompleted => migrationCompleted.Task;
+
+        private readonly TaskCompletionSource<bool> migrationCompleted = new TaskCompletionSource<bool>();
 
         [Resolved]
         private DatabaseContextFactory efContextFactory { get; set; } = null!;
@@ -99,6 +101,17 @@ namespace osu.Game.Database
             {
                 using (var ef = efContextFactory.Get())
                 {
+                    realmContextFactory.Write(realm =>
+                    {
+                        // Before beginning, ensure realm is in an empty state.
+                        // Migrations which are half-completed could lead to issues if the user tries a second time.
+                        // Note that we only do this for beatmaps and scores since the other migrations are yonks old.
+                        realm.RemoveAll<BeatmapSetInfo>();
+                        realm.RemoveAll<BeatmapInfo>();
+                        realm.RemoveAll<BeatmapMetadata>();
+                        realm.RemoveAll<ScoreInfo>();
+                    });
+
                     migrateSettings(ef);
                     migrateSkins(ef);
                     migrateBeatmaps(ef);
@@ -114,7 +127,7 @@ namespace osu.Game.Database
                     Logger.Log("Your development database has been fully migrated to realm. If you switch back to a pre-realm branch and need your previous database, rename the backup file back to \"client.db\".\n\nNote that doing this can potentially leave your file store in a bad state.", level: LogLevel.Important);
             }, TaskCreationOptions.LongRunning).ContinueWith(t =>
             {
-                FinishedMigrating = true;
+                migrationCompleted.SetResult(true);
             });
         }
 
@@ -149,14 +162,6 @@ namespace osu.Game.Database
             {
                 log($"Found {count} beatmaps in EF");
 
-                // only migrate data if the realm database is empty.
-                // note that this cannot be written as: `realm.All<BeatmapSetInfo>().All(s => s.Protected)`, because realm does not support `.All()`.
-                if (realm.All<BeatmapSetInfo>().Any(s => !s.Protected))
-                {
-                    log("Skipping migration as realm already has beatmaps loaded");
-                }
-                else
-                {
                 var transaction = realm.BeginWrite();
                 int written = 0;
 
@@ -229,7 +234,6 @@ namespace osu.Game.Database
                 }
 
                 log($"Successfully migrated {count} beatmaps to realm");
-                }
             });
         }
 
@@ -280,13 +284,6 @@ namespace osu.Game.Database
             {
                 log($"Found {count} scores in EF");
 
-                // only migrate data if the realm database is empty.
-                if (realm.All<ScoreInfo>().Any())
-                {
-                    log("Skipping migration as realm already has scores loaded");
-                }
-                else
-                {
                 var transaction = realm.BeginWrite();
                 int written = 0;
 
@@ -343,7 +340,6 @@ namespace osu.Game.Database
                 }
 
                 log($"Successfully migrated {count} scores to realm");
-                }
             });
         }
 

osu.Game/Screens/Loader.cs

@@ -74,11 +74,22 @@ namespace osu.Game.Screens
             base.OnEntering(last);
 
             LoadComponentAsync(precompiler = CreateShaderPrecompiler(), AddInternal);
-            LoadComponentAsync(loadableScreen = CreateLoadableScreen());
 
             // A non-null context factory means there's still content to migrate.
             if (efContextFactory != null)
+            {
                 LoadComponentAsync(realmMigrator = new EFToRealmMigrator(), AddInternal);
+                realmMigrator.MigrationCompleted.ContinueWith(_ => Schedule(() =>
+                {
+                    // Delay initial screen loading to ensure that the migration is in a complete and sane state
+                    // before the intro screen may import the game intro beatmap.
+                    LoadComponentAsync(loadableScreen = CreateLoadableScreen());
+                }));
+            }
+            else
+            {
+                LoadComponentAsync(loadableScreen = CreateLoadableScreen());
+            }
 
             LoadComponentAsync(spinner = new LoadingSpinner(true, true)
             {
@@ -96,7 +107,7 @@ namespace osu.Game.Screens
 
         private void checkIfLoaded()
         {
-            if (loadableScreen.LoadState != LoadState.Ready || !precompiler.FinishedCompiling || realmMigrator?.FinishedMigrating == false)
+            if (loadableScreen?.LoadState != LoadState.Ready || !precompiler.FinishedCompiling)
             {
                 Schedule(checkIfLoaded);
                 return;