Ensure metadata path is created on app startup, and also each time it is updated

Emby.Server.Implementations/Configuration/ServerConfigurationManager.cs

@@ -67,11 +67,15 @@ namespace Emby.Server.Implementations.Configuration
         /// <summary>
         /// Updates the metadata path.
         /// </summary>
+        /// <exception cref="UnauthorizedAccessException">If the directory does not exist, and the caller does not have the required permission to create it.</exception>
+        /// <exception cref="NotSupportedException">If there is a custom path transcoding path specified, but it is invalid.</exception>
+        /// <exception cref="IOException">If the directory does not exist, and it also could not be created.</exception>
         private void UpdateMetadataPath()
         {
             ((ServerApplicationPaths)ApplicationPaths).InternalMetadataPath = string.IsNullOrWhiteSpace(Configuration.MetadataPath)
-                ? Path.Combine(ApplicationPaths.ProgramDataPath, "metadata")
+                ? ApplicationPaths.DefaultInternalMetadataPath
                 : Configuration.MetadataPath;
+            Directory.CreateDirectory(ApplicationPaths.InternalMetadataPath);
         }
 
         /// <summary>

Emby.Server.Implementations/ServerApplicationPaths.cs

@@ -9,8 +9,6 @@ namespace Emby.Server.Implementations
     /// </summary>
     public class ServerApplicationPaths : BaseApplicationPaths, IServerApplicationPaths
     {
-        private string _internalMetadataPath;
-
         /// <summary>
         /// Initializes a new instance of the <see cref="ServerApplicationPaths" /> class.
         /// </summary>
@@ -27,6 +25,7 @@ namespace Emby.Server.Implementations
                 cacheDirectoryPath,
                 webDirectoryPath)
         {
+            InternalMetadataPath = DefaultInternalMetadataPath;
         }
 
         /// <summary>
@@ -98,12 +97,11 @@ namespace Emby.Server.Implementations
         /// <value>The user configuration directory path.</value>
         public string UserConfigurationDirectoryPath => Path.Combine(ConfigurationDirectoryPath, "users");
 
+        /// <inheritdoc/>
+        public string DefaultInternalMetadataPath => Path.Combine(ProgramDataPath, "metadata");
+
         /// <inheritdoc />
-        public string InternalMetadataPath
-        {
-            get => _internalMetadataPath ?? (_internalMetadataPath = Path.Combine(DataPath, "metadata"));
-            set => _internalMetadataPath = value;
-        }
+        public string InternalMetadataPath { get; set; }
 
         /// <inheritdoc />
         public string VirtualInternalMetadataPath { get; } = "%MetadataPath%";

MediaBrowser.Controller/IServerApplicationPaths.cs

@@ -71,7 +71,12 @@ namespace MediaBrowser.Controller
         string UserConfigurationDirectoryPath { get; }
 
         /// <summary>
-        /// Gets the internal metadata path.
+        /// Gets the default internal metadata path.
+        /// </summary>
+        string DefaultInternalMetadataPath { get; }
+
+        /// <summary>
+        /// Gets the internal metadata path, either a custom path or the default.
         /// </summary>
         /// <value>The internal metadata path.</value>
         string InternalMetadataPath { get; }