openapi-normalizer: Add REMOVE_PROPERTIES_FROM_TYPE_OTHER_THAN_OBJECT normalize option

docs/customization.md

@@ -644,6 +644,13 @@ Example:
 java -jar modules/openapi-generator-cli/target/openapi-generator-cli.jar generate -g java -i modules/openapi-generator/src/test/resources/3_0/required-properties.yaml -o /tmp/java-okhttp/ --openapi-normalizer NORMALIZER_CLASS=org.openapitools.codegen.OpenAPINormalizerTest$RemoveRequiredNormalizer
 ```
 
+- `REMOVE_PROPERTIES_FROM_TYPE_OTHER_THAN_OBJECT`: When set to true, remove the "properties" of a schema with type other than "object".
+
+Example:
+```
+java -jar modules/openapi-generator-cli/target/openapi-generator-cli.jar generate -g java -i modules/openapi-generator/src/test/resources/3_0/required-properties.yaml -o /tmp/java-okhttp/ --openapi-normalizer REMOVE_PROPERTIES_FROM_TYPE_OTHER_THAN_OBJECT=true
+```
+
 - `FILTER`
 
 The `FILTER` parameter allows selective inclusion of API operations based on specific criteria. It applies the `x-internal: true` property to operations that do **not** match the specified values, preventing them from being generated. Multiple filters can be separated by a semicolon.

modules/openapi-generator/src/main/java/org/openapitools/codegen/InlineModelResolver.java

@@ -356,7 +356,9 @@ private void gatherInlineModels(Schema schema, String modelPrefix) {
         } else if (schema.getProperties() != null) {
             // If non-object type is specified but also properties
             LOGGER.error("Illegal schema found with non-object type combined with properties," +
-                    " no properties should be defined:\n " + schema.toString());
+                    " no properties should be defined:" +
+                    " consider using --openapi-normalizer REMOVE_PROPERTIES_FROM_TYPE_OTHER_THAN_OBJECT=true\n " +
+                    schema.toString());
             return;
         } else if (schema.getAdditionalProperties() != null) {
             // If non-object type is specified but also additionalProperties

modules/openapi-generator/src/main/java/org/openapitools/codegen/OpenAPINormalizer.java

@@ -124,6 +124,9 @@ public class OpenAPINormalizer {
     // the allOf contains a new schema containing the properties in the top level
     final String REFACTOR_ALLOF_WITH_PROPERTIES_ONLY = "REFACTOR_ALLOF_WITH_PROPERTIES_ONLY";
 
+    // when set to true, remove the "properties" of a schema with type other than "object"
+    final String REMOVE_PROPERTIES_FROM_TYPE_OTHER_THAN_OBJECT = "REMOVE_PROPERTIES_FROM_TYPE_OTHER_THAN_OBJECT";
+
     // when set to true, normalize OpenAPI 3.1 spec to make it work with the generator
     final String NORMALIZE_31SPEC = "NORMALIZE_31SPEC";
 
@@ -206,6 +209,7 @@ public OpenAPINormalizer(OpenAPI openAPI, Map<String, String> inputRules) {
         ruleNames.add(SET_CONTAINER_TO_NULLABLE);
         ruleNames.add(SET_PRIMITIVE_TYPES_TO_NULLABLE);
         ruleNames.add(SIMPLIFY_ONEOF_ANYOF_ENUM);
+        ruleNames.add(REMOVE_PROPERTIES_FROM_TYPE_OTHER_THAN_OBJECT);
 
         // rules that are default to true
         rules.put(SIMPLIFY_ONEOF_ANYOF, true);
@@ -702,6 +706,8 @@ public Schema normalizeSchema(Schema schema, Set<Schema> visitedSchemas) {
 
         markSchemaAsVisited(schema, visitedSchemas);
 
+        processNormalizeOtherThanObjectWithProperties(schema);
+
         if (ModelUtils.isArraySchema(schema)) { // array
             Schema result = normalizeArraySchema(schema);
             normalizeSchema(result.getItems(), visitedSchemas);
@@ -1961,6 +1967,23 @@ private boolean hasOperationId(Operation operation) {
         private boolean hasMethod(String method) {
             return methodFilters.contains(method);
         }
+    }
 
+    /**
+     * When set to true, remove "properties" attribute on schema other than "object"
+     * since it should be ignored and may result in odd generated code
+     *
+     * @param schema         Schema
+     * @return Schema
+     */
+    protected void processNormalizeOtherThanObjectWithProperties(Schema schema) {
+        if (getRule(REMOVE_PROPERTIES_FROM_TYPE_OTHER_THAN_OBJECT)) {
+            // Check object models / any type models / composed models for properties,
+            // if the schema has a type defined that is not "object" it should not define
+            // any properties
+            if (schema.getType() != null && !"object".equals(schema.getType())) {
+                schema.setProperties(null);
+            }
+        }
     }
 }

modules/openapi-generator/src/test/java/org/openapitools/codegen/OpenAPINormalizerTest.java

@@ -26,6 +26,7 @@
 import org.openapitools.codegen.utils.ModelUtils;
 import org.testng.annotations.Test;
 
+import java.lang.reflect.Array;
 import java.util.*;
 
 import static org.testng.Assert.*;
@@ -36,6 +37,26 @@ public class OpenAPINormalizerTest {
     private static final String X_PARENT = "x-parent";
     private static final String X_INTERNAL = "x-internal";
 
+    @Test
+    public void testOpenAPINormalizerOtherThanObjectWithProperties()
+    {
+        // to test the rule REF_AS_PARENT_IN_ALLOF
+        OpenAPI openAPI = TestUtils.parseSpec("src/test/resources/3_0/issue_21680_array_with_properties.yaml");
+
+        Schema schema = openAPI.getComponents().getSchemas().get("errors");
+        assertNotNull(schema);
+        assertNotNull(schema.getProperties());
+
+        Map<String, String> options = new HashMap<>();
+        options.put("REMOVE_PROPERTIES_FROM_TYPE_OTHER_THAN_OBJECT", "true");
+        OpenAPINormalizer openAPINormalizer = new OpenAPINormalizer(openAPI, options);
+        openAPINormalizer.normalize();
+
+        Schema schema2 = openAPI.getComponents().getSchemas().get("errors");
+        assertNotNull(schema2);
+        assertNull(schema2.getProperties());
+    }
+
     @Test
     public void testOpenAPINormalizerRefAsParentInAllOf() {
         // to test the rule REF_AS_PARENT_IN_ALLOF

modules/openapi-generator/src/test/resources/3_0/issue_21680_array_with_properties.yaml

@@ -0,0 +1,48 @@
+---
+# Corresponds to bug report 21680: https://github.com/openapitools/openapi-generator/issues/21680
+openapi: 3.0.1
+info:
+  title: API that has problem with OpenAPI Generator
+  version: 1.0.0
+paths:
+  "/forbiddenaccesscsrf":
+    get:
+      summary: Forbidden access CSRF
+      operationId: forbiddenAccessCsrfGet
+      responses:
+        '403':
+          description: Expected response
+          content:
+            application/json:
+              schema:
+                "$ref": "#/components/schemas/errors"
+components:
+  schemas:
+    error:
+      required:
+      - code
+      - horodatage
+      - message
+      type: object
+      properties:
+        code:
+          type: string
+          description: Short error description
+        message:
+          type: string
+          description: Complete human readable description
+        error_uri:
+          type: string
+          description: Detailed error description URI
+          format: uri
+        horodatage:
+          type: string
+          description: Date time of occurence
+          format: date-time
+    errors:
+      type: array
+      properties:
+        empty:
+          type: boolean
+      items:
+        "$ref": "#/components/schemas/error"