1 files changed, 92 insertions, 0 deletions
diff --git a/Jellyfin.Server/Migrations.cs b/Jellyfin.Server/Migrations.cs
new file mode 100644
index 000000000..95fea4ea5
--- /dev/null
+++ b/Jellyfin.Server/Migrations.cs
@@ -0,0 +1,92 @@
+using System;
+using System.Collections.Generic;
+using MediaBrowser.Common.Configuration;
+using MediaBrowser.Model.Configuration;
+using Microsoft.Extensions.Logging;
+
+namespace Jellyfin.Server
+{
+    /// <summary>
+    /// The class that knows how migrate between different Jellyfin versions.
+    /// </summary>
+    internal static class Migrations
+    {
+        private static readonly IUpdater[] _migrations =
+        {
+            new Pre10_5()
+        };
+
+        /// <summary>
+        /// Interface that descibes a migration routine.
+        /// </summary>
+        private 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; }
+
+            /// <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>
+        /// 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)
+        {
+            bool updated = false;
+            var version = host.ServerConfigurationManager.CommonConfiguration.PreviousVersion;
+
+            for (var i = 0; i < _migrations.Length; i++)
+            {
+                var updater = _migrations[i];
+                if (version.CompareTo(updater.Maximum) >= 0)
+                {
+                    logger.LogDebug("Skipping updater {0} as current version {1} >= its maximum applicable version {2}", updater, version, updater.Maximum);
+                    continue;
+                }
+
+                if (updater.Perform(host, logger, version))
+                {
+                    updated = true;
+                }
+
+                version = updater.Maximum;
+            }
+
+            return updated;
+        }
+
+        private class Pre10_5 : IUpdater
+        {
+            public Version Maximum { get => Version.Parse("10.5.0"); }
+
+            public bool Perform(CoreAppHost host, ILogger logger, Version from)
+            {
+                // 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");
+                if (encoding.EnableThrottling)
+                {
+                    logger.LogInformation("Disabling transcoding throttling during migration");
+                    encoding.EnableThrottling = false;
+
+                    host.ServerConfigurationManager.SaveConfiguration("encoding", encoding);
+                    return true;
+                }
+
+                return false;
+            }
+        }
+    }
+}