Add support back for /emby and /mediabrowser routes

Jellyfin.Server/Extensions/ApiApplicationBuilderExtensions.cs

@@ -117,5 +117,18 @@ namespace Jellyfin.Server.Extensions
         {
             return appBuilder.UseMiddleware<RobotsRedirectionMiddleware>();
         }
+
+        /// <summary>
+        /// Adds /emby and /mediabrowser route trimming to the application pipeline.
+        /// </summary>
+        /// <remarks>
+        /// This must be injected before any path related middleware.
+        /// </remarks>
+        /// <param name="appBuilder">The application builder.</param>
+        /// <returns>The updated application builder.</returns>
+        public static IApplicationBuilder UsePathTrim(this IApplicationBuilder appBuilder)
+        {
+            return appBuilder.UseMiddleware<PathTrimMiddleware>();
+        }
     }
 }

Jellyfin.Server/Middleware/PathTrimMiddleware.cs

@@ -0,0 +1,54 @@
+using System;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Http;
+using Microsoft.Extensions.Logging;
+
+namespace Jellyfin.Server.Middleware
+{
+    /// <summary>
+    /// Removes /emby and /mediabrowser from requested route.
+    /// </summary>
+    public class PathTrimMiddleware
+    {
+        private const string EmbyPath = "/emby";
+        private const string MediabrowserPath = "/mediabrowser";
+
+        private readonly RequestDelegate _next;
+        private readonly ILogger<PathTrimMiddleware> _logger;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="PathTrimMiddleware"/> class.
+        /// </summary>
+        /// <param name="next">The next delegate in the pipeline.</param>
+        /// <param name="logger">The logger.</param>
+        public PathTrimMiddleware(
+            RequestDelegate next,
+            ILogger<PathTrimMiddleware> logger)
+        {
+            _next = next;
+            _logger = logger;
+        }
+
+        /// <summary>
+        /// Executes the middleware action.
+        /// </summary>
+        /// <param name="httpContext">The current HTTP context.</param>
+        /// <returns>The async task.</returns>
+        public async Task Invoke(HttpContext httpContext)
+        {
+            var localPath = httpContext.Request.Path.ToString();
+            if (localPath.StartsWith(EmbyPath, StringComparison.OrdinalIgnoreCase))
+            {
+                httpContext.Request.Path = localPath[EmbyPath.Length..];
+                _logger.LogDebug("Removing {EmbyPath} from route.", EmbyPath);
+            }
+            else if (localPath.StartsWith(MediabrowserPath, StringComparison.OrdinalIgnoreCase))
+            {
+                httpContext.Request.Path = localPath[MediabrowserPath.Length..];
+                _logger.LogDebug("Removing {MediabrowserPath} from route.", MediabrowserPath);
+            }
+
+            await _next(httpContext).ConfigureAwait(false);
+        }
+    }
+}

Jellyfin.Server/Startup.cs

@@ -128,6 +128,8 @@ namespace Jellyfin.Server
                     mainApp.UseHttpsRedirection();
                 }
 
+                // This must be injected before any path related middleware.
+                mainApp.UsePathTrim();
                 mainApp.UseStaticFiles();
                 if (appConfig.HostWebClient())
                 {