From 07e975a0ed5d7d8bd3f5cd83d54d1d59a12d7e62 Mon Sep 17 00:00:00 2001
From: James Newton-King <james@newtonking.com>
Date: Tue, 6 Jun 2017 17:52:18 +1200
Subject: [PATCH] Return a shared contract resolver

Return a shared contract resolver from CreateSerializerSettings for performance
---
 .../JsonSerializerSettingsProvider.cs              | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/src/Microsoft.AspNetCore.Mvc.Formatters.Json/JsonSerializerSettingsProvider.cs b/src/Microsoft.AspNetCore.Mvc.Formatters.Json/JsonSerializerSettingsProvider.cs
index 8dc4bf2d5c..8b6761559d 100644
--- a/src/Microsoft.AspNetCore.Mvc.Formatters.Json/JsonSerializerSettingsProvider.cs
+++ b/src/Microsoft.AspNetCore.Mvc.Formatters.Json/JsonSerializerSettingsProvider.cs
@@ -13,6 +13,13 @@ namespace Microsoft.AspNetCore.Mvc.Formatters
     {
         private const int DefaultMaxDepth = 32;
 
+        // return shared resolver by default for perf so slow reflection logic is cached once
+        // developers can set their own resolver after the settings are returned if desired
+        private static readonly DefaultContractResolver SharedContractResolver = new DefaultContractResolver
+        {
+            NamingStrategy = new CamelCaseNamingStrategy(),
+        };
+
         /// <summary>
         /// Creates default <see cref="JsonSerializerSettings"/>.
         /// </summary>
@@ -21,10 +28,7 @@ namespace Microsoft.AspNetCore.Mvc.Formatters
         {
             return new JsonSerializerSettings
             {
-                ContractResolver = new DefaultContractResolver
-                {
-                    NamingStrategy = new CamelCaseNamingStrategy(),
-                },
+                ContractResolver = SharedContractResolver,
 
                 MissingMemberHandling = MissingMemberHandling.Ignore,
 
@@ -38,4 +42,4 @@ namespace Microsoft.AspNetCore.Mvc.Formatters
             };
         }
     }
-}
\ No newline at end of file
+}