chore(library): serialize contains keywords as v3 extensions

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: baywet

src/Microsoft.OpenApi/Models/OpenApiConstants.cs

@@ -895,6 +895,21 @@ public static class OpenApiConstants
         /// </summary>
         public const string ContentSchemaExtension = "x-jsonschema-contentSchema";
 
+        /// <summary>
+        /// Extension: x-jsonschema-contains
+        /// </summary>
+        public const string ContainsExtension = "x-jsonschema-contains";
+
+        /// <summary>
+        /// Extension: x-jsonschema-maxContains
+        /// </summary>
+        public const string MaxContainsExtension = "x-jsonschema-maxContains";
+
+        /// <summary>
+        /// Extension: x-jsonschema-minContains
+        /// </summary>
+        public const string MinContainsExtension = "x-jsonschema-minContains";
+
         #region V2.0
 
         /// <summary>

src/Microsoft.OpenApi/Models/OpenApiSchema.cs

@@ -713,6 +713,9 @@ private void WriteV3CompatibilityKeywords(IOpenApiWriter writer, Action<IOpenApi
             writer.WriteProperty(OpenApiConstants.ContentEncodingExtension, ContentEncoding);
             writer.WriteProperty(OpenApiConstants.ContentMediaTypeExtension, ContentMediaType);
             writer.WriteOptionalObject(OpenApiConstants.ContentSchemaExtension, ContentSchema, callback);
+            writer.WriteOptionalObject(OpenApiConstants.ContainsExtension, Contains, callback);
+            writer.WriteProperty(OpenApiConstants.MaxContainsExtension, MaxContains);
+            writer.WriteProperty(OpenApiConstants.MinContainsExtension, MinContains);
             writer.WriteOptionalObject(OpenApiConstants.PropertyNamesExtension, PropertyNames, callback);
             writer.WriteOptionalMap(OpenApiConstants.DependentSchemasExtension, DependentSchemas, callback);
             writer.WriteOptionalObject(OpenApiConstants.IfExtension, If, callback);

src/Microsoft.OpenApi/PublicAPI.Unshipped.txt

@@ -10,12 +10,15 @@ const Microsoft.OpenApi.OpenApiConstants.ContentMediaType = "contentMediaType" -
 const Microsoft.OpenApi.OpenApiConstants.ContentMediaTypeExtension = "x-jsonschema-contentMediaType" -> string!
 const Microsoft.OpenApi.OpenApiConstants.ContentSchema = "contentSchema" -> string!
 const Microsoft.OpenApi.OpenApiConstants.ContentSchemaExtension = "x-jsonschema-contentSchema" -> string!
+const Microsoft.OpenApi.OpenApiConstants.ContainsExtension = "x-jsonschema-contains" -> string!
 const Microsoft.OpenApi.OpenApiConstants.DependentSchemas = "dependentSchemas" -> string!
 const Microsoft.OpenApi.OpenApiConstants.DependentSchemasExtension = "x-jsonschema-dependentSchemas" -> string!
 const Microsoft.OpenApi.OpenApiConstants.Else = "else" -> string!
 const Microsoft.OpenApi.OpenApiConstants.ElseExtension = "x-jsonschema-else" -> string!
 const Microsoft.OpenApi.OpenApiConstants.If = "if" -> string!
 const Microsoft.OpenApi.OpenApiConstants.IfExtension = "x-jsonschema-if" -> string!
+const Microsoft.OpenApi.OpenApiConstants.MaxContainsExtension = "x-jsonschema-maxContains" -> string!
+const Microsoft.OpenApi.OpenApiConstants.MinContainsExtension = "x-jsonschema-minContains" -> string!
 const Microsoft.OpenApi.OpenApiConstants.PropertyNames = "propertyNames" -> string!
 const Microsoft.OpenApi.OpenApiConstants.PropertyNamesExtension = "x-jsonschema-propertyNames" -> string!
 const Microsoft.OpenApi.OpenApiConstants.Then = "then" -> string!

test/Microsoft.OpenApi.Tests/Models/OpenApiSchemaTests.cs

@@ -1279,9 +1279,8 @@ public async Task SerializeContainsKeywordsAsV31Works()
         }
 
         [Fact]
-        public async Task SerializeContainsKeywordsAsV3DoesNotEmit()
+        public async Task SerializeContainsKeywordsAsV3EmitsCompatibilityExtensions()
         {
-            // Arrange - contains/minContains/maxContains are JSON Schema 2020-12 keywords and have no equivalent in OpenAPI 3.0
             var schema = new OpenApiSchema
             {
                 Type = JsonSchemaType.Array,
@@ -1302,7 +1301,12 @@ public async Task SerializeContainsKeywordsAsV3DoesNotEmit()
             var expectedV3Schema =
                 """
                 {
-                  "type": "array"
+                  "type": "array",
+                  "x-jsonschema-contains": {
+                    "type": "string"
+                  },
+                  "x-jsonschema-maxContains": 5,
+                  "x-jsonschema-minContains": 1
                 }
                 """;
 
@@ -1521,6 +1525,11 @@ public async Task SerializeMissingPropertiesEmitsOaiExtensionsInV3()
                   "x-jsonschema-contentSchema": {
                     "type": "array"
                   },
+                  "x-jsonschema-contains": {
+                    "type": "string"
+                  },
+                  "x-jsonschema-maxContains": 3,
+                  "x-jsonschema-minContains": 1,
                   "x-jsonschema-propertyNames": {
                     "pattern": "^[a-z]+$"
                   },
@@ -1549,6 +1558,9 @@ public async Task SerializeMissingPropertiesEmitsOaiExtensionsInV3()
                 ContentEncoding = "base64",
                 ContentMediaType = "application/jwt",
                 ContentSchema = new OpenApiSchema { Type = JsonSchemaType.Array },
+                Contains = new OpenApiSchema { Type = JsonSchemaType.String },
+                MaxContains = 3,
+                MinContains = 1,
                 PropertyNames = new OpenApiSchema { Pattern = "^[a-z]+$" },
                 DependentSchemas = new Dictionary<string, IOpenApiSchema>
                 {