Fix serializing a null In

Add a few more tests

Author: PerthCharern

src/Microsoft.OpenApi.Readers/V2/OpenApiParameterDeserializer.cs

@@ -218,12 +218,13 @@ private static void ProcessIn(OpenApiParameter o, ParseNode n)
 
                     formParameters.Add(o);
                     break;
-                case "null":
-                case null:
-                    o.In = null;
+                case "query":
+                case "header":
+                case "path":
+                    o.In = value.GetEnumFromDisplayName<ParameterLocation>();
                     break;
                 default:
-                    o.In = value.GetEnumFromDisplayName<ParameterLocation>();
+                    o.In = null;
                     break;
             }
         }

src/Microsoft.OpenApi.Readers/V3/OpenApiParameterDeserializer.cs

@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license. 
 
-using System.Collections.Generic;
+using System;
 using System.Linq;
 using Microsoft.OpenApi.Extensions;
 using Microsoft.OpenApi.Models;
@@ -28,13 +28,16 @@ internal static partial class OpenApiV3Deserializer
                     "in", (o, n) =>
                     {
                         var inString = n.GetScalarValue();
-                        if ( inString == null || inString == "null" )
+
+                        if ( Enum.GetValues(typeof(ParameterLocation)).Cast<ParameterLocation>()
+                            .Select( e => e.GetDisplayName() )
+                            .Contains(inString) )
                         {
-                            o.In = null;
+                            o.In = n.GetScalarValue().GetEnumFromDisplayName<ParameterLocation>();
                         }
                         else
                         {
-                            o.In = n.GetScalarValue().GetEnumFromDisplayName<ParameterLocation>();
+                            o.In = null;
                         }
                     }
                 },
@@ -123,7 +126,6 @@ public static OpenApiParameter LoadParameter(ParseNode node)
             }
 
             var parameter = new OpenApiParameter();
-            var required = new List<string> {"name", "in"};
 
             ParseMap(mapNode, parameter, _parameterFixedFields, _parameterPatternFields);
 

src/Microsoft.OpenApi/Models/OpenApiParameter.cs

@@ -159,7 +159,7 @@ public void SerializeAsV3WithoutReference(IOpenApiWriter writer)
             writer.WriteProperty(OpenApiConstants.Name, Name);
 
             // in
-            writer.WriteProperty(OpenApiConstants.In, In.GetDisplayName());
+            writer.WriteProperty(OpenApiConstants.In, In?.GetDisplayName());
 
             // description
             writer.WriteProperty(OpenApiConstants.Description, Description);
@@ -237,7 +237,7 @@ public void SerializeAsV2WithoutReference(IOpenApiWriter writer)
             }
             else
             {
-                writer.WriteProperty(OpenApiConstants.In, In.GetDisplayName());
+                writer.WriteProperty(OpenApiConstants.In, In?.GetDisplayName());
             }
 
             // name

test/Microsoft.OpenApi.Readers.Tests/Microsoft.OpenApi.Readers.Tests.csproj

@@ -49,6 +49,9 @@
       <EmbeddedResource Include="V2Tests\Samples\OpenApiParameter\parameterWithNoLocation.yaml">
         <CopyToOutputDirectory>Never</CopyToOutputDirectory>
       </EmbeddedResource>
+      <EmbeddedResource Include="V2Tests\Samples\OpenApiParameter\parameterWithUnknownLocation.yaml">
+        <CopyToOutputDirectory>Never</CopyToOutputDirectory>
+      </EmbeddedResource>
       <EmbeddedResource Include="V2Tests\Samples\OpenApiParameter\parameterWithNullLocation.yaml">
         <CopyToOutputDirectory>Never</CopyToOutputDirectory>
       </EmbeddedResource>
@@ -119,13 +122,21 @@
       <EmbeddedResource Include="V3Tests\Samples\OpenApiInfo\minimalInfo.yaml">
         <CopyToOutputDirectory>Never</CopyToOutputDirectory>
       </EmbeddedResource>
-      <EmbeddedResource Include="V3Tests\Samples\OpenApiOperation\securedOperation.yaml" />
+      <EmbeddedResource Include="V3Tests\Samples\OpenApiOperation\operationWithParameterWithNoLocation.json">
+       <CopyToOutputDirectory>Never</CopyToOutputDirectory>
+      </EmbeddedResource>
+      <EmbeddedResource Include="V3Tests\Samples\OpenApiOperation\securedOperation.yaml">
+       <CopyToOutputDirectory>Never</CopyToOutputDirectory>
+      </EmbeddedResource>
       <EmbeddedResource Include="V3Tests\Samples\OpenApiParameter\headerParameter.yaml">
         <CopyToOutputDirectory>Never</CopyToOutputDirectory>
       </EmbeddedResource>
       <EmbeddedResource Include="V3Tests\Samples\OpenApiParameter\parameterWithNoLocation.yaml">
         <CopyToOutputDirectory>Never</CopyToOutputDirectory>
       </EmbeddedResource>
+      <EmbeddedResource Include="V3Tests\Samples\OpenApiParameter\parameterWithUnknownLocation.yaml">
+        <CopyToOutputDirectory>Never</CopyToOutputDirectory>
+      </EmbeddedResource>
       <EmbeddedResource Include="V3Tests\Samples\OpenApiParameter\parameterWithNullLocation.yaml">
         <CopyToOutputDirectory>Never</CopyToOutputDirectory>
       </EmbeddedResource>

test/Microsoft.OpenApi.Readers.Tests/V2Tests/OpenApiParameterTests.cs

@@ -224,5 +224,33 @@ public void ParseParameterWithNoLocationShouldSucceed()
                     }
                 });
         }
+
+        [Fact]
+        public void ParseParameterWithUnknownLocationShouldSucceed()
+        {
+            // Arrange
+            MapNode node;
+            using ( var stream = Resources.GetStream(Path.Combine(SampleFolderPath, "parameterWithUnknownLocation.yaml")) )
+            {
+                node = TestHelper.CreateYamlMapNode(stream);
+            }
+
+            // Act
+            var parameter = OpenApiV2Deserializer.LoadParameter(node);
+
+            // Assert
+            parameter.ShouldBeEquivalentTo(
+                new OpenApiParameter
+                {
+                    In = null,
+                    Name = "username",
+                    Description = "username to fetch",
+                    Required = true,
+                    Schema = new OpenApiSchema
+                    {
+                        Type = "string"
+                    }
+                });
+        }
     }
 }

test/Microsoft.OpenApi.Readers.Tests/V2Tests/Samples/OpenApiParameter/parameterWithUnknownLocation.yaml

@@ -0,0 +1,5 @@
+name: username
+in: abcde
+description: username to fetch
+required: true
+type: string

test/Microsoft.OpenApi.Readers.Tests/V3Tests/OpenApiOperationTests.cs

@@ -3,6 +3,10 @@
 
 using System.IO;
 using System.Linq;
+using FluentAssertions;
+using Microsoft.OpenApi.Models;
+using Microsoft.OpenApi.Readers.ParseNodes;
+using Microsoft.OpenApi.Readers.V3;
 using Xunit;
 
 namespace Microsoft.OpenApi.Readers.Tests.V3Tests
@@ -24,6 +28,62 @@ public void OperationWithSecurityRequirementShouldReferenceSecurityScheme()
             }
         }
 
-     
+        [Fact]
+        public void ParseOperationWithParameterWithNoLocationShouldSucceed()
+        {
+            // Arrange
+            MapNode node;
+            using ( var stream = Resources.GetStream(Path.Combine(SampleFolderPath, "operationWithParameterWithNoLocation.json")) )
+            {
+                node = TestHelper.CreateYamlMapNode(stream);
+            }
+
+            // Act
+            var operation = OpenApiV3Deserializer.LoadOperation(node);
+
+            // Assert
+            operation.ShouldBeEquivalentTo(new OpenApiOperation()
+            {
+                Tags =
+                {
+                    new OpenApiTag
+                    {
+                        UnresolvedReference = true,
+                        Reference = new OpenApiReference()
+                        {
+                            Id = "user",
+                            Type = ReferenceType.Tag
+                        }
+                    }
+                },
+                Summary = "Logs user into the system",
+                Description = "",
+                OperationId = "loginUser",
+                Parameters =
+                {
+                    new OpenApiParameter
+                    {
+                        Name = "username",
+                        Description = "The user name for login",
+                        Required = true,
+                        Schema = new OpenApiSchema
+                        {
+                            Type = "string"
+                        }
+                    },
+                    new OpenApiParameter
+                    {
+                        Name = "password",
+                        Description = "The password for login in clear text",
+                        In = ParameterLocation.Query,
+                        Required = true,
+                        Schema = new OpenApiSchema
+                        {
+                            Type = "string"
+                        }
+                    }
+                }
+            });
+        }
     }
 }

test/Microsoft.OpenApi.Readers.Tests/V3Tests/OpenApiParameterTests.cs

@@ -246,5 +246,33 @@ public void ParseParameterWithNoLocationShouldSucceed()
                     }
                 });
         }
+
+        [Fact]
+        public void ParseParameterWithUnknownLocationShouldSucceed()
+        {
+            // Arrange
+            MapNode node;
+            using ( var stream = Resources.GetStream(Path.Combine(SampleFolderPath, "parameterWithUnknownLocation.yaml")) )
+            {
+                node = TestHelper.CreateYamlMapNode(stream);
+            }
+
+            // Act
+            var parameter = OpenApiV3Deserializer.LoadParameter(node);
+
+            // Assert
+            parameter.ShouldBeEquivalentTo(
+                new OpenApiParameter
+                {
+                    In = null,
+                    Name = "username",
+                    Description = "username to fetch",
+                    Required = true,
+                    Schema = new OpenApiSchema
+                    {
+                        Type = "string"
+                    }
+                });
+        }
     }
 }

test/Microsoft.OpenApi.Readers.Tests/V3Tests/Samples/OpenApiOperation/operationWithParameterWithNoLocation.json

@@ -0,0 +1,25 @@
+{
+    "tags": [ "user" ],
+    "summary": "Logs user into the system",
+    "description": "",
+    "operationId": "loginUser",
+    "parameters": [
+        {
+            "name": "username",
+            "description": "The user name for login",
+            "required": true,
+            "schema": {
+                "type": "string"
+            }
+        },
+        {
+            "name": "password",
+            "in": "query",
+            "description": "The password for login in clear text",
+            "required": true,
+            "schema": {
+                "type": "string"
+            }
+        }
+    ]
+}

test/Microsoft.OpenApi.Readers.Tests/V3Tests/Samples/OpenApiParameter/parameterWithUnknownLocation.yaml

@@ -0,0 +1,6 @@
+name: username
+in: null
+description: username to fetch
+required: true
+schema:
+  type: string