1 files changed, 91 insertions, 0 deletions
diff --git a/Jellyfin.Server/Migrations/Stages/CodeMigration.cs b/Jellyfin.Server/Migrations/Stages/CodeMigration.cs
new file mode 100644
index 000000000..264710bce
--- /dev/null
+++ b/Jellyfin.Server/Migrations/Stages/CodeMigration.cs
@@ -0,0 +1,91 @@
+using System;
+using System.Globalization;
+using System.Threading;
+using System.Threading.Tasks;
+using Jellyfin.Server.ServerSetupApp;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.DependencyInjection.Extensions;
+using Microsoft.Extensions.Logging;
+
+namespace Jellyfin.Server.Migrations.Stages;
+
+internal class CodeMigration(Type migrationType, JellyfinMigrationAttribute metadata, JellyfinMigrationBackupAttribute? migrationBackupAttribute)
+{
+    public Type MigrationType { get; } = migrationType;
+
+    public JellyfinMigrationAttribute Metadata { get; } = metadata;
+
+    public JellyfinMigrationBackupAttribute? BackupRequirements { get; set; } = migrationBackupAttribute;
+
+    public string BuildCodeMigrationId()
+    {
+        return Metadata.Order.ToString("yyyyMMddHHmmsss", CultureInfo.InvariantCulture) + "_" + Metadata.Name!;
+    }
+
+    private IServiceCollection MigrationServices(IServiceProvider serviceProvider, IStartupLogger logger)
+    {
+        var childServiceCollection = new ServiceCollection()
+            .AddSingleton(serviceProvider)
+            .AddSingleton(logger)
+            .AddSingleton(typeof(IStartupLogger<>), typeof(NestedStartupLogger<>))
+            .AddSingleton<StartupLogTopic>(logger.Topic!);
+
+        foreach (ServiceDescriptor service in serviceProvider.GetRequiredService<IServiceCollection>())
+        {
+            if (service.Lifetime == ServiceLifetime.Singleton && !service.ServiceType.IsGenericTypeDefinition)
+            {
+                object? serviceInstance = serviceProvider.GetService(service.ServiceType);
+                if (serviceInstance != null)
+                {
+                    childServiceCollection.AddSingleton(service.ServiceType, serviceInstance);
+                    continue;
+                }
+            }
+
+            childServiceCollection.Add(service);
+        }
+
+        return childServiceCollection;
+    }
+
+    public async Task Perform(IServiceProvider? serviceProvider, IStartupLogger logger, CancellationToken cancellationToken)
+    {
+#pragma warning disable CS0618 // Type or member is obsolete
+        if (typeof(IMigrationRoutine).IsAssignableFrom(MigrationType))
+        {
+            if (serviceProvider is null)
+            {
+                ((IMigrationRoutine)Activator.CreateInstance(MigrationType)!).Perform();
+            }
+            else
+            {
+                using var migrationServices = MigrationServices(serviceProvider, logger).BuildServiceProvider();
+                ((IMigrationRoutine)ActivatorUtilities.CreateInstance(migrationServices, MigrationType)).Perform();
+#pragma warning restore CS0618 // Type or member is obsolete
+            }
+        }
+        else if (typeof(IAsyncMigrationRoutine).IsAssignableFrom(MigrationType))
+        {
+            if (serviceProvider is null)
+            {
+                await ((IAsyncMigrationRoutine)Activator.CreateInstance(MigrationType)!).PerformAsync(cancellationToken).ConfigureAwait(false);
+            }
+            else
+            {
+                using var migrationServices = MigrationServices(serviceProvider, logger).BuildServiceProvider();
+                await ((IAsyncMigrationRoutine)ActivatorUtilities.CreateInstance(migrationServices, MigrationType)).PerformAsync(cancellationToken).ConfigureAwait(false);
+            }
+        }
+        else
+        {
+            throw new InvalidOperationException($"The type {MigrationType} does not implement either IMigrationRoutine or IAsyncMigrationRoutine and is not a valid migration type");
+        }
+    }
+
+    private class NestedStartupLogger<TCategory> : StartupLogger<TCategory>
+    {
+        public NestedStartupLogger(ILogger logger, StartupLogTopic topic) : base(logger, topic)
+        {
+        }
+    }
+}