An OpenApi (swagger) parser to generate MappingModel or mapping.json file (#479)

* wip

* .

* .

* nuget

* .

* .

* WithMappingModel

* tests

* json

* codefactor

* sign

* .

* interface

* sln

* comments

src/WireMock.Net.OpenApiParser/Utils/ExampleValueGenerator.cs

@@ -0,0 +1,51 @@
+using System;
+using Microsoft.OpenApi.Models;
+using WireMock.Net.OpenApiParser.Extensions;
+using WireMock.Net.OpenApiParser.Types;
+
+namespace WireMock.Net.OpenApiParser.Utils
+{
+    internal static class ExampleValueGenerator
+    {
+        public static object GetExampleValue(OpenApiSchema schema)
+        {
+            switch (schema?.GetSchemaType())
+            {
+                case SchemaType.Boolean:
+                    return true;
+
+                case SchemaType.Integer:
+                    return 42;
+
+                case SchemaType.Number:
+                    switch (schema?.GetSchemaFormat())
+                    {
+                        case SchemaFormat.Float:
+                            return 4.2f;
+
+                        default:
+                            return 4.2d;
+                    }
+
+                default:
+                    switch (schema?.GetSchemaFormat())
+                    {
+                        case SchemaFormat.Date:
+                            return DateTimeUtils.ToRfc3339Date(DateTime.UtcNow);
+
+                        case SchemaFormat.DateTime:
+                            return DateTimeUtils.ToRfc3339DateTime(DateTime.UtcNow);
+
+                        case SchemaFormat.Byte:
+                            return new byte[] { 48, 49, 50 };
+
+                        case SchemaFormat.Binary:
+                            return "example-object";
+
+                        default:
+                            return "example-string";
+                    }
+            }
+        }
+    }
+}