fix #13150 Add uniqueModelMappings option

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

@@ -267,6 +267,8 @@ apiTemplateFiles are for API outputs only (controllers/handlers).
     // Support legacy logic for evaluating discriminators
     protected boolean legacyDiscriminatorBehavior = true;
 
+    private boolean uniqueModelMappings = false;
+
     // Specify what to do if the 'additionalProperties' keyword is not present in a schema.
     // See CodegenConstants.java for more details.
     protected boolean disallowAdditionalPropertiesIfNotPresent = true;
@@ -1365,6 +1367,14 @@ public void setLegacyDiscriminatorBehavior(boolean val) {
         this.legacyDiscriminatorBehavior = val;
     }
 
+    public boolean isUniqueModelMappings() {
+        return uniqueModelMappings;
+    }
+
+    public void setUniqueModelMappings(boolean uniqueModelMappings) {
+        this.uniqueModelMappings = uniqueModelMappings;
+    }
+
     public Boolean getDisallowAdditionalPropertiesIfNotPresent() {
         return disallowAdditionalPropertiesIfNotPresent;
     }
@@ -3361,13 +3371,19 @@ protected List<MappedModel> getAllOfDescendants(String thisSchemaName, OpenAPI o
                 break;
             }
             currentSchemaName = queue.remove(0);
-            MappedModel mm = new MappedModel(currentSchemaName, toModelName(currentSchemaName));
-            descendentSchemas.add(mm);
             Schema cs = schemas.get(currentSchemaName);
             Map<String, Object> vendorExtensions = cs.getExtensions();
-            if (vendorExtensions != null && !vendorExtensions.isEmpty() && vendorExtensions.containsKey("x-discriminator-value")) {
+            boolean hasDiscriminatorValue =
+                vendorExtensions != null && !vendorExtensions.isEmpty()
+                    && vendorExtensions.containsKey("x-discriminator-value");
+
+            if (!uniqueModelMappings || !hasDiscriminatorValue) {
+                MappedModel mm = new MappedModel(currentSchemaName, toModelName(currentSchemaName));
+                descendentSchemas.add(mm);
+            }
+            if (hasDiscriminatorValue) {
                 String xDiscriminatorValue = (String) vendorExtensions.get("x-discriminator-value");
-                mm = new MappedModel(xDiscriminatorValue, toModelName(currentSchemaName));
+                MappedModel mm = new MappedModel(xDiscriminatorValue, toModelName(currentSchemaName));
                 descendentSchemas.add(mm);
             }
         }
@@ -3422,7 +3438,8 @@ protected CodegenDiscriminator createDiscriminator(String schemaName, Schema sch
                 // add only if the mapping names are not the same
                 boolean matched = false;
                 for (MappedModel uniqueDescendant : uniqueDescendants) {
-                    if (uniqueDescendant.getMappingName().equals(otherDescendant.getMappingName())) {
+                    if (uniqueDescendant.getMappingName().equals(otherDescendant.getMappingName())
+                        || (uniqueModelMappings && uniqueDescendant.getModelName().equals(otherDescendant.getModelName()))) {
                         matched = true;
                         break;
                     }

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

@@ -951,6 +951,26 @@ public void testDiscriminatorWithCustomMapping() {
         Assert.assertEquals(personModel.getHasDiscriminatorWithNonEmptyMapping(), true);
     }
 
+    @Test
+    public void testUniqueMappingDiscriminatorWithCustomMapping() {
+        final OpenAPI openAPI = TestUtils.parseFlattenSpec("src/test/resources/3_0/allOf.yaml");
+        DefaultCodegen codegen = new DefaultCodegen();
+        codegen.setLegacyDiscriminatorBehavior(false);
+        codegen.setOpenAPI(openAPI);
+        codegen.setUniqueModelMappings(true);
+
+        String path = "/person/display/{personId}";
+        Operation operation = openAPI.getPaths().get(path).getGet();
+        CodegenOperation codegenOperation = codegen.fromOperation(path, "GET", operation, null);
+        verifyPersonDiscriminatorWithUniqueMappings(codegenOperation.discriminator);
+
+        Schema person = openAPI.getComponents().getSchemas().get("Person");
+        codegen.setOpenAPI(openAPI);
+        CodegenModel personModel = codegen.fromModel("Person", person);
+        verifyPersonDiscriminatorWithUniqueMappings(personModel.discriminator);
+        Assert.assertEquals(personModel.getHasDiscriminatorWithNonEmptyMapping(), true);
+    }
+
     @Test
     public void testParentName() {
         final OpenAPI openAPI = TestUtils.parseFlattenSpec("src/test/resources/3_0/allOf.yaml");
@@ -1592,6 +1612,54 @@ public void verifyXDiscriminatorValue() {
         assertEquals(cm.discriminator, discriminator);
     }
 
+    @Test
+    public void verifyXDiscriminatorValueWithUniqueMappingNames() {
+        final OpenAPI openAPI = TestUtils.parseFlattenSpec("src/test/resources/2_0/x-discriminator-value.yaml");
+        final DefaultCodegen config = new DefaultCodegen();
+        config.setOpenAPI(openAPI);
+        config.setUniqueModelMappings(true);
+
+        String modelName;
+        CodegenDiscriminator discriminator;
+        CodegenModel cm;
+
+        Boolean dryRun = Boolean.TRUE;
+        final DefaultGenerator generator = new DefaultGenerator(dryRun);
+        generator.openAPI = openAPI;
+        generator.config = config;
+        generator.configureGeneratorProperties();
+
+        // for us to check a model's children we need to run generator.generateModels
+        // because children are assigned in config.updateAllModels which is invoked in generator.generateModels
+        List<File> files = new ArrayList<>();
+        List<String> filteredSchemas = ModelUtils.getSchemasUsedOnlyInFormParam(openAPI);
+        List<ModelMap> allModels = new ArrayList<>();
+        generator.generateModels(files, allModels, filteredSchemas);
+
+        // check that the model's children contain the x-discriminator-values
+        modelName = "BaseObj";
+        cm = getModel(allModels, modelName);
+        Assert.assertNotNull(cm);
+        Assert.assertNotNull(cm.children);
+        List<String> expectedDiscriminatorValues = new ArrayList<>(Arrays.asList("daily", "sub-obj"));
+        ArrayList<String> xDiscriminatorValues = new ArrayList<>();
+        for (CodegenModel child : cm.children) {
+            xDiscriminatorValues.add((String) child.vendorExtensions.get("x-discriminator-value"));
+        }
+        assertEquals(xDiscriminatorValues, expectedDiscriminatorValues);
+
+        // check that the discriminator's MappedModels also contains the x-discriminator-values
+        discriminator = new CodegenDiscriminator();
+        String prop = "object_type";
+        discriminator.setPropertyName(config.toVarName(prop));
+        discriminator.setPropertyBaseName(prop);
+        discriminator.setMapping(null);
+        discriminator.setMappedModels(new HashSet<CodegenDiscriminator.MappedModel>() {{
+            add(new CodegenDiscriminator.MappedModel("daily", "DailySubObj"));
+            add(new CodegenDiscriminator.MappedModel("sub-obj", "SubObj"));
+        }});
+        assertEquals(cm.discriminator, discriminator);
+    }
 
     @Test
     public void testAllOfSingleRefNoOwnProps() {
@@ -1996,6 +2064,18 @@ private void verifyPersonDiscriminator(CodegenDiscriminator discriminator) {
         Assert.assertEquals(discriminator, test);
     }
 
+    private void verifyPersonDiscriminatorWithUniqueMappings(CodegenDiscriminator discriminator) {
+        CodegenDiscriminator test = new CodegenDiscriminator();
+        test.setPropertyName("DollarUnderscoretype");
+        test.setPropertyBaseName("$_type");
+        test.setMapping(new HashMap<>());
+        test.getMapping().put("a", "#/components/schemas/Adult");
+        test.getMapping().put("c", "Child");
+        test.getMappedModels().add(new CodegenDiscriminator.MappedModel("a", "Adult"));
+        test.getMappedModels().add(new CodegenDiscriminator.MappedModel("c", "Child"));
+        Assert.assertEquals(discriminator, test);
+    }
+
     private CodegenProperty codegenPropertyWithArrayOfIntegerValues() {
         CodegenProperty array = new CodegenProperty();
         final CodegenProperty items = new CodegenProperty();

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

@@ -1079,6 +1079,45 @@ public void testOneOfAndAllOf() throws IOException {
         assertFileContains(Paths.get(outputPath + "/src/main/java/org/openapitools/model/PizzaSpeziale.java"), "import java.math.BigDecimal");
     }
 
+    @Test
+    public void testMappingSubtypesIssue13150() throws IOException {
+        File output = Files.createTempDirectory("test").toFile().getCanonicalFile();
+        output.deleteOnExit();
+        String outputPath = output.getAbsolutePath().replace('\\', '/');
+        OpenAPI openAPI = new OpenAPIParser()
+                .readLocation("src/test/resources/bugs/issue_13150.yaml", null, new ParseOptions()).getOpenAPI();
+
+        SpringCodegen codegen = new SpringCodegen();
+        codegen.setOutputDir(output.getAbsolutePath());
+        codegen.additionalProperties().put(CXFServerFeatures.LOAD_TEST_DATA_FROM_FILE, "true");
+        codegen.setUseOneOfInterfaces(true);
+        codegen.setUniqueModelMappings(true);
+
+        ClientOptInput input = new ClientOptInput();
+        input.openAPI(openAPI);
+        input.config(codegen);
+
+        DefaultGenerator generator = new DefaultGenerator();
+        codegen.setHateoas(true);
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODELS, "true");
+        generator.setGeneratorPropertyDefault(CodegenConstants.LEGACY_DISCRIMINATOR_BEHAVIOR, "false");
+
+        codegen.setUseOneOfInterfaces(true);
+        codegen.setLegacyDiscriminatorBehavior(false);
+
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODEL_TESTS, "false");
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODEL_DOCS, "false");
+        generator.setGeneratorPropertyDefault(CodegenConstants.APIS, "true");
+        generator.setGeneratorPropertyDefault(CodegenConstants.SUPPORTING_FILES, "false");
+
+        generator.opts(input).generate();
+
+        String jsonSubType = "@JsonSubTypes({\n" +
+            "  @JsonSubTypes.Type(value = Foo.class, name = \"foo\")\n" +
+            "})";
+        assertFileContains(Paths.get(outputPath + "/src/main/java/org/openapitools/model/Parent.java"), jsonSubType);
+    }
+
     @Test
     public void testTypeMappings() {
         final SpringCodegen codegen = new SpringCodegen();

modules/openapi-generator/src/test/resources/bugs/issue_13150.yaml

@@ -0,0 +1,60 @@
+openapi: '3.0.0'
+info:
+  version: '1.0.0'
+  title: 'FooService'
+paths:
+  /parent:
+    put:
+      summary: put parent
+      operationId: putParent
+      parameters:
+        - name: name
+          in: path
+          required: true
+          description: Name of the account being updated.
+          schema:
+            type: string
+      requestBody:
+        description: The updated account definition to save.
+        required: true
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/Parent'
+      responses:
+        '200':
+          $ref: '#/components/responses/Parent'
+components:
+  schemas:
+    Parent:
+      type: object
+      description: Defines an account by name.
+      properties:
+        name:
+          type: string
+          description: The account name.
+        type:
+          type: string
+          description: The account type discriminator.
+      required:
+        - name
+        - type
+      discriminator:
+        propertyName: type
+        mapping:
+          foo: '#/components/schemas/Foo'
+
+    Foo:
+      allOf:
+        - $ref: "#/components/schemas/Parent"
+        - type: object
+          properties:
+            fooType:
+              type: string
+  responses:
+    Parent:
+      description: The saved account definition.
+      content:
+        application/json:
+          schema:
+            $ref: '#/components/schemas/Parent'