From aef61a70c09a5bd5d4402a887d3d2c1eb1018f1e Mon Sep 17 00:00:00 2001
From: Aaron <apatters@microsoft.com>
Date: Fri, 14 Apr 2023 13:50:01 -0700
Subject: [PATCH] Ensure ApiPath does not get a NullReferenceExcepton when
 copying common parameters to operation method parameters. (#5914)

Previously, when the operation method does not have any parameters a null refference exception occurs when attempting to copy the common parameters to the operation metod.
---
 .../SwaggerApiParser/SwaggerSpec/ApiPath.cs         |  5 +++++
 .../SwaggerApiParserTest/fixtures/azureopenai.json  | 13 +++++--------
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/tools/apiview/parsers/swagger-api-parser/SwaggerApiParser/SwaggerSpec/ApiPath.cs b/tools/apiview/parsers/swagger-api-parser/SwaggerApiParser/SwaggerSpec/ApiPath.cs
index 9221de5672a..d4e19940ae5 100644
--- a/tools/apiview/parsers/swagger-api-parser/SwaggerApiParser/SwaggerSpec/ApiPath.cs
+++ b/tools/apiview/parsers/swagger-api-parser/SwaggerApiParser/SwaggerSpec/ApiPath.cs
@@ -36,6 +36,11 @@ public Dictionary<string, Operation> operations
                 {
                     if (this.parameters != null)
                     {
+                        if (operation.parameters == null)
+                        {
+                            operation.parameters = new List<Parameter>();
+                        }
+
                         operation.parameters.AddRange(this.parameters);
                     }   
                     ret.Add(method, operation);
diff --git a/tools/apiview/parsers/swagger-api-parser/SwaggerApiParserTest/fixtures/azureopenai.json b/tools/apiview/parsers/swagger-api-parser/SwaggerApiParserTest/fixtures/azureopenai.json
index 034e5dd6417..c068825b347 100644
--- a/tools/apiview/parsers/swagger-api-parser/SwaggerApiParserTest/fixtures/azureopenai.json
+++ b/tools/apiview/parsers/swagger-api-parser/SwaggerApiParserTest/fixtures/azureopenai.json
@@ -7,6 +7,11 @@
   },
   "paths": {
     "/deployments": {
+      "parameters": [
+        {
+          "$ref": "#/parameters/apiVersionQueryParameter"
+        }
+      ],
       "get": {
         "tags": [
           "Deployments:"
@@ -16,11 +21,6 @@
         "produces": [
           "application/json"
         ],
-        "parameters": [
-          {
-            "$ref": "#/parameters/apiVersionQueryParameter"
-          }
-        ],
         "responses": {
           "200": {
             "description": "Success",
@@ -54,9 +54,6 @@
           "application/json"
         ],
         "parameters": [
-          {
-            "$ref": "#/parameters/apiVersionQueryParameter"
-          },
           {
             "in": "body",
             "name": "body",