Move Middleware to Jellyfin.Api

Jellyfin.Api/Middleware/ServerStartupMessageMiddleware.cs

@@ -0,0 +1,51 @@
+using System;
+using System.Net.Mime;
+using System.Threading.Tasks;
+using MediaBrowser.Controller;
+using MediaBrowser.Model.Globalization;
+using Microsoft.AspNetCore.Http;
+
+namespace Jellyfin.Api.Middleware
+{
+    /// <summary>
+    /// Shows a custom message during server startup.
+    /// </summary>
+    public class ServerStartupMessageMiddleware
+    {
+        private readonly RequestDelegate _next;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ServerStartupMessageMiddleware"/> class.
+        /// </summary>
+        /// <param name="next">The next delegate in the pipeline.</param>
+        public ServerStartupMessageMiddleware(RequestDelegate next)
+        {
+            _next = next;
+        }
+
+        /// <summary>
+        /// Executes the middleware action.
+        /// </summary>
+        /// <param name="httpContext">The current HTTP context.</param>
+        /// <param name="serverApplicationHost">The server application host.</param>
+        /// <param name="localizationManager">The localization manager.</param>
+        /// <returns>The async task.</returns>
+        public async Task Invoke(
+            HttpContext httpContext,
+            IServerApplicationHost serverApplicationHost,
+            ILocalizationManager localizationManager)
+        {
+            if (serverApplicationHost.CoreStartupHasCompleted
+                || httpContext.Request.Path.Equals("/system/ping", StringComparison.OrdinalIgnoreCase))
+            {
+                await _next(httpContext).ConfigureAwait(false);
+                return;
+            }
+
+            var message = localizationManager.GetLocalizedString("StartupEmbyServerIsLoading");
+            httpContext.Response.StatusCode = StatusCodes.Status503ServiceUnavailable;
+            httpContext.Response.ContentType = MediaTypeNames.Text.Html;
+            await httpContext.Response.WriteAsync(message, httpContext.RequestAborted).ConfigureAwait(false);
+        }
+    }
+}