Improve migration logic

Jellyfin.Server/CoreAppHost.cs

@@ -57,33 +57,5 @@ namespace Jellyfin.Server
 
         /// <inheritdoc />
         protected override void ShutdownInternal() => Program.Shutdown();
-
-        /// <summary>
-        /// Runs the migration routines if necessary.
-        /// </summary>
-        public void TryMigrate()
-        {
-            var previousVersion = ConfigurationManager.CommonConfiguration.PreviousVersion;
-            switch (ApplicationVersion.CompareTo(previousVersion))
-            {
-                case 1:
-                    Logger.LogWarning("Version check shows Jellyfin was updated: previous version={0}, current version={1}", previousVersion, ApplicationVersion);
-
-                    Migrations.MigrationRunner.Run(this, Logger);
-
-                    ConfigurationManager.CommonConfiguration.PreviousVersion = ApplicationVersion;
-                    ConfigurationManager.SaveConfiguration();
-                    break;
-                case 0:
-                    // nothing to do, versions match
-                    break;
-                case -1:
-                    Logger.LogWarning("Version check shows Jellyfin was rolled back, use at your own risk: previous version={0}, current version={1}", previousVersion, ApplicationVersion);
-                    // no "rollback" routines for now
-                    ConfigurationManager.CommonConfiguration.PreviousVersion = ApplicationVersion;
-                    ConfigurationManager.SaveConfiguration();
-                    break;
-            }
-        }
     }
 }

Jellyfin.Server/Migrations/DisableTranscodingThrottling.cs

@@ -1,6 +1,8 @@
 using System;
+using System.IO;
 using MediaBrowser.Common.Configuration;
 using MediaBrowser.Model.Configuration;
+using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.Logging;
 
 namespace Jellyfin.Server.Migrations
@@ -8,13 +10,13 @@ namespace Jellyfin.Server.Migrations
     /// <summary>
     /// Updater that takes care of bringing configuration up to 10.5.0 standards.
     /// </summary>
-    internal class Pre_10_5 : IUpdater
+    internal class DisableTranscodingThrottling : IUpdater
     {
         /// <inheritdoc/>
-        public Version Maximum { get => Version.Parse("10.5.0"); }
+        public string Name => "DisableTranscodingThrottling";
 
         /// <inheritdoc/>
-        public bool Perform(CoreAppHost host, ILogger logger, Version from)
+        public void Perform(CoreAppHost host, ILogger logger)
         {
             // Set EnableThrottling to false as it wasn't used before, and in 10.5.0 it may introduce issues
             var encoding = ((IConfigurationManager)host.ServerConfigurationManager).GetConfiguration<EncodingOptions>("encoding");
@@ -24,10 +26,7 @@ namespace Jellyfin.Server.Migrations
                 encoding.EnableThrottling = false;
 
                 host.ServerConfigurationManager.SaveConfiguration("encoding", encoding);
-                return true;
             }
-
-            return false;
         }
     }
 }

Jellyfin.Server/Migrations/DisableZealousLogging.cs

@@ -0,0 +1,29 @@
+using System;
+using System.IO;
+using MediaBrowser.Common.Configuration;
+using MediaBrowser.Model.Configuration;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.Logging;
+using Serilog;
+using ILogger = Microsoft.Extensions.Logging.ILogger;
+
+namespace Jellyfin.Server.Migrations
+{
+    /// <summary>
+    /// Updater that takes care of bringing configuration up to 10.5.0 standards.
+    /// </summary>
+    internal class DisableZealousLogging : IUpdater
+    {
+        /// <inheritdoc/>
+        public string Name => "DisableZealousLogging";
+
+        /// <inheritdoc/>
+        // This tones down logging from some components
+        public void Perform(CoreAppHost host, ILogger logger)
+        {
+            string configPath = Path.Combine(host.ServerConfigurationManager.ApplicationPaths.ConfigurationDirectoryPath, Program.LoggingConfigFile);
+            // TODO: fix up the config
+            throw new NotImplementedException("don't know how to fix logging yet");
+        }
+    }
+}

Jellyfin.Server/Migrations/IUpdater.cs

@@ -3,24 +3,21 @@ using Microsoft.Extensions.Logging;
 
 namespace Jellyfin.Server.Migrations
 {
+    /// <summary>
+    /// Interface that descibes a migration routine.
+    /// </summary>
+    internal interface IUpdater
+    {
         /// <summary>
-        /// Interface that descibes a migration routine.
+        /// Gets the name of the migration, must be unique.
         /// </summary>
-        internal interface IUpdater
-        {
-            /// <summary>
-            /// Gets maximum version this Updater applies to.
-            /// If current version is greater or equal to it, skip the updater.
-            /// </summary>
-            public abstract Version Maximum { get; }
+        public abstract string Name { get; }
 
-            /// <summary>
-            /// Execute the migration from version "from".
-            /// </summary>
-            /// <param name="host">Host that hosts current version.</param>
-            /// <param name="logger">Host logger.</param>
-            /// <param name="from">Version to migrate from.</param>
-            /// <returns>Whether configuration was changed.</returns>
-            public abstract bool Perform(CoreAppHost host, ILogger logger, Version from);
-        }
+        /// <summary>
+        /// Execute the migration from version "from".
+        /// </summary>
+        /// <param name="host">Host that hosts current version.</param>
+        /// <param name="logger">Host logger.</param>
+        public abstract void Perform(CoreAppHost host, ILogger logger);
+    }
 }

Jellyfin.Server/Migrations/MigrationOptions.cs

@@ -0,0 +1,23 @@
+namespace Jellyfin.Server.Migrations
+{
+    /// <summary>
+    /// Configuration part that holds all migrations that were applied.
+    /// </summary>
+    public class MigrationOptions
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="MigrationOptions"/> class.
+        /// </summary>
+        public MigrationOptions()
+        {
+            Applied = System.Array.Empty<string>();
+        }
+
+#pragma warning disable CA1819 // Properties should not return arrays
+        /// <summary>
+        /// Gets or sets he list of applied migration routine names.
+        /// </summary>
+        public string[] Applied { get; set; }
+#pragma warning restore CA1819 // Properties should not return arrays
+    }
+}

Jellyfin.Server/Migrations/MigrationRunner.cs

@@ -1,3 +1,6 @@
+using System;
+using System.Linq;
+using MediaBrowser.Common.Configuration;
 using Microsoft.Extensions.Logging;
 
 namespace Jellyfin.Server.Migrations
@@ -5,42 +8,56 @@ namespace Jellyfin.Server.Migrations
     /// <summary>
     /// The class that knows how migrate between different Jellyfin versions.
     /// </summary>
-    public static class MigrationRunner
+    public sealed class MigrationRunner
     {
-        private static readonly IUpdater[] _migrations =
+        /// <summary>
+        /// The list of known migrations, in order of applicability.
+        /// </summary>
+        internal static readonly IUpdater[] Migrations =
         {
-            new Pre_10_5()
+            new DisableTranscodingThrottling(),
+            new DisableZealousLogging()
         };
 
         /// <summary>
         /// Run all needed migrations.
         /// </summary>
         /// <param name="host">CoreAppHost that hosts current version.</param>
-        /// <param name="logger">AppHost logger.</param>
-        /// <returns>Whether anything was changed.</returns>
-        public static bool Run(CoreAppHost host, ILogger logger)
+        /// <param name="loggerFactory">Factory for making the logger.</param>
+        public static void Run(CoreAppHost host, ILoggerFactory loggerFactory)
         {
-            bool updated = false;
-            var version = host.ServerConfigurationManager.CommonConfiguration.PreviousVersion;
+            var logger = loggerFactory.CreateLogger<MigrationRunner>();
+            var migrationOptions = ((IConfigurationManager)host.ServerConfigurationManager).GetConfiguration<MigrationOptions>("migrations");
+            var applied = migrationOptions.Applied.ToList();
 
-            for (var i = 0; i < _migrations.Length; i++)
+            for (var i = 0; i < Migrations.Length; i++)
             {
-                var updater = _migrations[i];
-                if (version.CompareTo(updater.Maximum) >= 0)
+                var updater = Migrations[i];
+                if (applied.Contains(updater.Name))
                 {
-                    logger.LogDebug("Skipping updater {0} as current version {1} >= its maximum applicable version {2}", updater, version, updater.Maximum);
+                    logger.LogDebug("Skipping migration {0} as it is already applied", updater.Name);
                     continue;
                 }
 
-                if (updater.Perform(host, logger, version))
+                try
                 {
-                    updated = true;
+                    updater.Perform(host, logger);
+                }
+                catch (Exception ex)
+                {
+                    logger.LogError(ex, "Cannot apply migration {0}", updater.Name);
+                    continue;
                 }
 
-                version = updater.Maximum;
+                applied.Add(updater.Name);
             }
 
-            return updated;
+            if (applied.Count > migrationOptions.Applied.Length)
+            {
+                logger.LogInformation("Some migrations were run, saving the state");
+                migrationOptions.Applied = applied.ToArray();
+                host.ServerConfigurationManager.SaveConfiguration("migrations", migrationOptions);
+            }
         }
     }
 }

Jellyfin.Server/Migrations/MigrationsFactory.cs

@@ -0,0 +1,20 @@
+using System.Collections.Generic;
+using MediaBrowser.Common.Configuration;
+
+namespace Jellyfin.Server.Migrations
+{
+    /// <summary>
+    /// A factory that teachs Jellyfin how to find a peristent file which lists all applied migrations.
+    /// </summary>
+    public class MigrationsFactory : IConfigurationFactory
+    {
+        /// <inheritdoc/>
+        public IEnumerable<ConfigurationStore> GetConfigurations()
+        {
+            return new[]
+            {
+                new MigrationsListStore()
+            };
+        }
+    }
+}

Jellyfin.Server/Migrations/MigrationsListStore.cs

@@ -0,0 +1,19 @@
+using MediaBrowser.Common.Configuration;
+
+namespace Jellyfin.Server.Migrations
+{
+    /// <summary>
+    /// A configuration that lists all the migration routines that were applied.
+    /// </summary>
+    public class MigrationsListStore : ConfigurationStore
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="MigrationsListStore"/> class.
+        /// </summary>
+        public MigrationsListStore()
+        {
+            ConfigurationType = typeof(MigrationOptions);
+            Key = "migrations";
+        }
+    }
+}

Jellyfin.Server/Program.cs

@@ -38,6 +38,11 @@ namespace Jellyfin.Server
     /// </summary>
     public static class Program
     {
+        /// <summary>
+        /// The name of logging configuration file.
+        /// </summary>
+        public static readonly string LoggingConfigFile = "logging.json";
+
         private static readonly CancellationTokenSource _tokenSource = new CancellationTokenSource();
         private static readonly ILoggerFactory _loggerFactory = new SerilogLoggerFactory();
         private static ILogger _logger = NullLogger.Instance;
@@ -182,7 +187,7 @@ namespace Jellyfin.Server
                 // A bit hacky to re-use service provider since ASP.NET doesn't allow a custom service collection.
                 appHost.ServiceProvider = host.Services;
                 appHost.FindParts();
-                appHost.TryMigrate();
+                Migrations.MigrationRunner.Run(appHost, _loggerFactory);
 
                 try
                 {
@@ -438,7 +443,7 @@ namespace Jellyfin.Server
         private static async Task<IConfiguration> CreateConfiguration(IApplicationPaths appPaths)
         {
             const string ResourcePath = "Jellyfin.Server.Resources.Configuration.logging.json";
-            string configPath = Path.Combine(appPaths.ConfigurationDirectoryPath, "logging.json");
+            string configPath = Path.Combine(appPaths.ConfigurationDirectoryPath, LoggingConfigFile);
 
             if (!File.Exists(configPath))
             {
@@ -460,7 +465,7 @@ namespace Jellyfin.Server
             return new ConfigurationBuilder()
                 .SetBasePath(appPaths.ConfigurationDirectoryPath)
                 .AddInMemoryCollection(ConfigurationOptions.Configuration)
-                .AddJsonFile("logging.json", false, true)
+                .AddJsonFile(LoggingConfigFile, false, true)
                 .AddEnvironmentVariables("JELLYFIN_")
                 .Build();
         }