Changes as requested

tests/Jellyfin.Server.Integration.Tests/Controllers/EncoderController.cs

@@ -0,0 +1,35 @@
+using System.Collections.Generic;
+using System.Linq;
+using Jellyfin.Api.Constants;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Mvc;
+
+namespace Jellyfin.Api.Controllers
+{
+    /// <summary>
+    /// Controller for testing the encoded url.
+    /// </summary>
+    public class EncoderController : BaseJellyfinApiController
+    {
+        /// <summary>
+        /// Tests the url decoding.
+        /// </summary>
+        /// <param name="params">Parameters to echo back in the response.</param>
+        /// <returns>An <see cref="OkResult"/>.</returns>
+        /// <response code="200">Information retrieved.</response>
+        [HttpGet("UrlDecode")]
+        [ProducesResponseType(StatusCodes.Status200OK)]
+        public ContentResult TestUrlDecoding([FromQuery]Dictionary<string, string>? @params = null)
+        {
+            return new ContentResult()
+            {
+                Content = (@params != null && @params.Count > 0)
+                    ? string.Join("&", @params.Select(x => x.Key + "=" + x.Value))
+                    : string.Empty,
+                ContentType = "text/plain; charset=utf-8",
+                StatusCode = 200
+            };
+        }
+    }
+}