reworked serialization

src/Core/Core/Execution/JsonQueryResultSerializer.cs

@@ -128,7 +128,7 @@ private static void WriteLocations(Utf8JsonWriter writer, IReadOnlyList<Location
 
                 writer.WriteStartArray();
 
-                for (int i = 0; i < locations.Count; i++)
+                for (var i = 0; i < locations.Count; i++)
                 {
                     WriteLocation(writer, locations[i]);
                 }
@@ -153,7 +153,7 @@ private static void WritePath(Utf8JsonWriter writer, IReadOnlyList<object> path)
 
                 writer.WriteStartArray();
 
-                for (int i = 0; i < path.Count; i++)
+                for (var i = 0; i < path.Count; i++)
                 {
                     switch (path[i])
                     {
@@ -212,17 +212,15 @@ private static void WritePath(Utf8JsonWriter writer, IReadOnlyList<object> path)
         {
             writer.WriteStartArray();
 
-            for (int i = 0; i < list.Count; i++)
+            for (var i = 0; i < list.Count; i++)
             {
                 WriteFieldValue(writer, list[i]);
             }
 
             writer.WriteEndArray();
         }
 
-        private static void WriteFieldValue(
-            Utf8JsonWriter writer,
-            object value)
+        private static void WriteFieldValue(Utf8JsonWriter writer,  object value)
         {
             if (value is null)
             {
@@ -292,10 +290,13 @@ private static void WritePath(Utf8JsonWriter writer, IReadOnlyList<object> path)
                     writer.WriteStringValue(n.Value);
                     break;
 
+                case Uri u:
+                    writer.WriteStringValue(u.ToString());
+                    break;
+
                 default:
-                    throw new NotSupportedException(
-                        $"The specified type `{value.GetType().FullName}` " +
-                        "is not supported by the result serializer.");
+                    writer.WriteStringValue(value.ToString());
+                    break;
             }
         }
     }

src/Core/Types/Types/Scalars/UrlType.cs

@@ -84,7 +84,7 @@ public override object Serialize(object value)
 
             if (value is Uri uri)
             {
-                return uri;
+                return uri.ToString();
             }
 
             throw new ScalarSerializationException(

src/Server/AspNetCore.Tests/PostMiddlewareTests.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Collections.Generic;
 using System.Net;
 using System.Net.Http;
@@ -897,6 +898,38 @@ public async Task HttpPost_Ensure_Scoped_Services_Work()
             result.MatchSnapshot();
         }
 
+        [Fact]
+        public async Task JsonSerializer_Handles_Serialization_Correctly()
+        {
+            // arrange
+            TestServer server = ServerFactory.Create(
+                services =>
+                {
+                    services.AddScoped<ScopedService>();
+                    services.AddGraphQL(
+                        SchemaBuilder.New()
+                            .AddQueryType<Query>());
+                },
+                app =>
+                    app.UseGraphQL());
+
+            var request =
+                @"
+                    {
+                        validUri
+                    }
+                ";
+            var contentType = "application/graphql";
+
+            // act
+            HttpResponseMessage message =
+                await server.SendPostRequestAsync(request, contentType, null);
+
+            // assert
+            ClientQueryResult result = await DeserializeAsync(message);
+            result.MatchSnapshot();
+        }
+
         public class ScopedService
         {
             public int Count { get; private set; }
@@ -906,5 +939,10 @@ public void Increase()
                 Count += 1;
             }
         }
+
+        public class Query
+        {
+            public Uri ValidUri() => new Uri("https://github.com/ChilliCream/hotchocolate");
+        }
     }
 }

src/Server/AspNetCore.Tests/__snapshots__/PostMiddlewareTests.JsonSerializer_Handles_Serialization_Correctly.snap

@@ -0,0 +1,7 @@
+{
+  "Data": {
+    "validUri": "https://github.com/ChilliCream/hotchocolate"
+  },
+  "Errors": null,
+  "Extensions": null
+}