From b1b68f56a77c24ab9068eac2aad19c1815781669 Mon Sep 17 00:00:00 2001
From: Maggie Kimani <maggiekim42@gmail.com>
Date: Thu, 6 Oct 2022 15:27:43 +0300
Subject: [PATCH] Insert null check validation when response header does not
 contain any schema during V2 deserialization

---
 .../V2/OpenApiHeaderDeserializer.cs            | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/src/Microsoft.OpenApi.Readers/V2/OpenApiHeaderDeserializer.cs b/src/Microsoft.OpenApi.Readers/V2/OpenApiHeaderDeserializer.cs
index 32caf86aa..5d6cc2ff3 100644
--- a/src/Microsoft.OpenApi.Readers/V2/OpenApiHeaderDeserializer.cs
+++ b/src/Microsoft.OpenApi.Readers/V2/OpenApiHeaderDeserializer.cs
@@ -1,4 +1,4 @@
-// Copyright (c) Microsoft Corporation. All rights reserved.
+// Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license. 
 
 using System;
@@ -139,8 +139,12 @@ internal static partial class OpenApiV2Deserializer
                 {
                     OpenApiConstants.Default,
                     new AnyFieldMapParameter<OpenApiHeader>(
-                        p => p.Schema.Default,
-                        (p, v) => p.Schema.Default = v,
+                        p => p.Schema?.Default,
+                        (p, v) => 
+                        {
+                            if(p.Schema == null) return;
+                            p.Schema.Default = v; 
+                        },
                         p => p.Schema)
                 }
             };
@@ -151,8 +155,12 @@ internal static partial class OpenApiV2Deserializer
                 {
                     OpenApiConstants.Enum,
                     new AnyListFieldMapParameter<OpenApiHeader>(
-                        p => p.Schema.Enum,
-                        (p, v) => p.Schema.Enum = v,
+                        p => p.Schema?.Enum,
+                        (p, v) =>
+                        {
+                            if(p.Schema == null) return;
+                            p.Schema.Enum = v; 
+                        },
                         p => p.Schema)
                 },
             };