Unified migration handling (#13950)

3 files changed, 93 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..1e4dfb237
--- /dev/null
+++ b/Jellyfin.Server/Migrations/Stages/CodeMigration.cs
@@ -0,0 +1,51 @@
+using System;
+using System.Globalization;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Jellyfin.Server.Migrations.Stages;
+
+internal class CodeMigration(Type migrationType, JellyfinMigrationAttribute metadata)
+{
+    public Type MigrationType { get; } = migrationType;
+
+    public JellyfinMigrationAttribute Metadata { get; } = metadata;
+
+    public string BuildCodeMigrationId()
+    {
+        return Metadata.Order.ToString("yyyyMMddHHmmsss", CultureInfo.InvariantCulture) + "_" + MigrationType.Name!;
+    }
+
+    public async Task Perform(IServiceProvider? serviceProvider, 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+#pragma warning disable CS0618 // Type or member is obsolete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
+            {
+                ((IMigrationRoutine)ActivatorUtilities.CreateInstance(serviceProvider, 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+#pragma warning restore CS0618 // Type or member is obsolete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
+            {
+                await ((IAsyncMigrationRoutine)ActivatorUtilities.CreateInstance(serviceProvider, 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");
+        }
+    }
+}
diff --git a/Jellyfin.Server/Migrations/Stages/JellyfinMigrationStageTypes.cs b/Jellyfin.Server/Migrations/Stages/JellyfinMigrationStageTypes.cs
new file mode 100644
index 000000000..d90ad3d9b
--- /dev/null
+++ b/Jellyfin.Server/Migrations/Stages/JellyfinMigrationStageTypes.cs
@@ -0,0 +1,26 @@
+namespace Jellyfin.Server.Migrations.Stages;
+
+/// <summary>
+/// Defines the stages the <see cref="JellyfinMigrationService"/> supports.
+/// </summary>
+#pragma warning disable CA1008 // Enums should have zero value
+public enum JellyfinMigrationStageTypes
+#pragma warning restore CA1008 // Enums should have zero value
+{
+    /// <summary>
+    /// Runs before services are initialised.
+    /// Reserved for migrations that are modifying the application server itself. Should be avoided if possible.
+    /// </summary>
+    PreInitialisation = 1,
+
+    /// <summary>
+    /// Runs after the host has been configured and includes the database migrations.
+    /// Allows the mix order of migrations that contain application code and database changes.
+    /// </summary>
+    CoreInitialisaition = 2,
+
+    /// <summary>
+    /// Runs after services has been registered and initialised. Last step before running the server.
+    /// </summary>
+    AppInitialisation = 3
+}
diff --git a/Jellyfin.Server/Migrations/Stages/MigrationStage.cs b/Jellyfin.Server/Migrations/Stages/MigrationStage.cs
new file mode 100644
index 000000000..efcadbf00
--- /dev/null
+++ b/Jellyfin.Server/Migrations/Stages/MigrationStage.cs
@@ -0,0 +1,16 @@
+using System.Collections.ObjectModel;
+
+namespace Jellyfin.Server.Migrations.Stages;
+
+/// <summary>
+/// Defines a Stage that can be Invoked and Handled at different times from the code.
+/// </summary>
+internal class MigrationStage : Collection<CodeMigration>
+{
+    public MigrationStage(JellyfinMigrationStageTypes stage)
+    {
+        Stage = stage;
+    }
+
+    public JellyfinMigrationStageTypes Stage { get; }
+}