OpenAPI Generator Return type Improvements

openapi-generator/src/main/java/io/micronaut/openapi/generator/AbstractMicronautJavaCodegen.java

@@ -79,7 +79,8 @@ public abstract class AbstractMicronautJavaCodegen<T extends GeneratorOptionsBui
     public static final String OPT_DATE_FORMAT = "dateFormat";
     public static final String OPT_DATETIME_FORMAT = "datetimeFormat";
     public static final String OPT_REACTIVE = "reactive";
-    public static final String OPT_WRAP_IN_HTTP_RESPONSE = "wrapInHttpResponse";
+    public static final String OPT_GENERATE_HTTP_RESPONSE_ALWAYS = "generateHttpResponseAlways";
+    public static final String OPT_GENERATE_HTTP_RESPONSE_WHERE_REQUIRED = "generateHttpResponseWhereRequired";
     public static final String OPT_APPLICATION_NAME = "applicationName";
     public static final String OPT_GENERATE_SWAGGER_ANNOTATIONS = "generateSwaggerAnnotations";
     public static final String OPT_GENERATE_SWAGGER_ANNOTATIONS_SWAGGER_1 = "swagger1";
@@ -99,7 +100,8 @@ public abstract class AbstractMicronautJavaCodegen<T extends GeneratorOptionsBui
     protected String testTool;
     protected boolean requiredPropertiesInConstructor = true;
     protected boolean reactive;
-    protected boolean wrapInHttpResponse;
+    protected boolean generateHttpResponseAlways;
+    protected boolean generateHttpResponseWhereRequired = true;
     protected String appName;
     protected String generateSwaggerAnnotations;
     protected boolean generateOperationOnlyForFirstTag;
@@ -128,7 +130,6 @@ protected AbstractMicronautJavaCodegen() {
         modelDocPath = "docs/models";
         dateLibrary = OPT_DATE_LIBRARY_ZONED_DATETIME;
         reactive = true;
-        wrapInHttpResponse = false;
         appName = artifactId;
         generateSwaggerAnnotations = this instanceof JavaMicronautClientCodegen ?
             OPT_GENERATE_SWAGGER_ANNOTATIONS_FALSE : OPT_GENERATE_SWAGGER_ANNOTATIONS_SWAGGER_2;
@@ -168,7 +169,8 @@ protected AbstractMicronautJavaCodegen() {
         cliOptions.add(CliOption.newBoolean(OPT_VISITABLE, "Generate visitor for subtypes with a discriminator", visitable));
         cliOptions.add(CliOption.newBoolean(OPT_REQUIRED_PROPERTIES_IN_CONSTRUCTOR, "Allow only to create models with all the required properties provided in constructor", requiredPropertiesInConstructor));
         cliOptions.add(CliOption.newBoolean(OPT_REACTIVE, "Make the responses use Reactor Mono as wrapper", reactive));
-        cliOptions.add(CliOption.newBoolean(OPT_WRAP_IN_HTTP_RESPONSE, "Wrap the response in HttpResponse object", wrapInHttpResponse));
+        cliOptions.add(CliOption.newBoolean(OPT_GENERATE_HTTP_RESPONSE_ALWAYS, "Always wrap the operations response in HttpResponse object", generateHttpResponseAlways));
+        cliOptions.add(CliOption.newBoolean(OPT_GENERATE_HTTP_RESPONSE_WHERE_REQUIRED, "Wrap the operations response in HttpResponse object where non-200 HTTP status codes or additional headers are defined", generateHttpResponseWhereRequired));
         cliOptions.add(CliOption.newBoolean(OPT_GENERATE_OPERATION_ONLY_FOR_FIRST_TAG, "When false, the operation method will be duplicated in each of the tags if multiple tags are assigned to this operation. " +
                                                                                        "If true, each operation will be generated only once in the first assigned tag.", generateOperationOnlyForFirstTag));
         CliOption testToolOption = new CliOption(OPT_TEST, "Specify which test tool to generate files for").defaultValue(testTool);
@@ -219,8 +221,12 @@ protected AbstractMicronautJavaCodegen() {
         importMapping.put("LocalDate", "java.time.LocalDate");
     }
 
-    public void setWrapInHttpResponse(boolean wrapInHttpResponse) {
-        this.wrapInHttpResponse = wrapInHttpResponse;
+    public void setGenerateHttpResponseAlways(boolean generateHttpResponseAlways) {
+        this.generateHttpResponseAlways = generateHttpResponseAlways;
+    }
+
+    public void setGenerateHttpResponseWhereRequired(boolean generateHttpResponseWhereRequired) {
+        this.generateHttpResponseWhereRequired = generateHttpResponseWhereRequired;
     }
 
     public void setReactive(boolean reactive) {
@@ -302,10 +308,14 @@ public void processOpts() {
         }
         writePropertyBack(OPT_REACTIVE, reactive);
 
-        if (additionalProperties.containsKey(OPT_WRAP_IN_HTTP_RESPONSE)) {
-            wrapInHttpResponse = convertPropertyToBoolean(OPT_WRAP_IN_HTTP_RESPONSE);
+        if (additionalProperties.containsKey(OPT_GENERATE_HTTP_RESPONSE_ALWAYS)) {
+            generateHttpResponseAlways = convertPropertyToBoolean(OPT_GENERATE_HTTP_RESPONSE_ALWAYS);
+        }
+        writePropertyBack(OPT_GENERATE_HTTP_RESPONSE_ALWAYS, generateHttpResponseAlways);
+        if (additionalProperties.containsKey(OPT_GENERATE_HTTP_RESPONSE_WHERE_REQUIRED)) {
+            generateHttpResponseWhereRequired = convertPropertyToBoolean(OPT_GENERATE_HTTP_RESPONSE_WHERE_REQUIRED);
         }
-        writePropertyBack(OPT_WRAP_IN_HTTP_RESPONSE, wrapInHttpResponse);
+        writePropertyBack(OPT_GENERATE_HTTP_RESPONSE_WHERE_REQUIRED, generateHttpResponseWhereRequired);
 
         if (additionalProperties.containsKey(OPT_GENERATE_OPERATION_ONLY_FOR_FIRST_TAG)) {
             generateOperationOnlyForFirstTag = convertPropertyToBoolean(OPT_GENERATE_OPERATION_ONLY_FOR_FIRST_TAG);
@@ -605,12 +615,6 @@ public CodegenParameter fromParameter(Parameter param, Set<String> imports) {
         return parameter;
     }
 
-    @Override
-    public boolean getUseInlineModelResolver() {
-        // This will allow TODO
-        return false;
-    }
-
     @Override
     public CodegenOperation fromOperation(
             String path, String httpMethod, Operation operation, List<Server> servers
@@ -626,6 +630,7 @@ public CodegenOperation fromOperation(
         op.vendorExtensions.put("originReturnProperty", op.returnProperty);
         processParametersWithAdditionalMappings(op.allParams, op.imports);
         processWithResponseBodyMapping(op);
+        processOperationWithResponseWrappers(op);
 
         return op;
     }
@@ -699,23 +704,60 @@ private void processWithResponseBodyMapping(CodegenOperation op) {
         }
 
         if (bodyMapping != null) {
-            CodegenProperty newProperty = new CodegenProperty();
-            newProperty.required = true;
-            newProperty.isModel = bodyMapping.isValidated;
+            wrapOperationReturnType(op, bodyMapping.mappedBodyType,
+                bodyMapping.isValidated, bodyMapping.isListWrapper);
+        }
+    }
+
+    /**
+     * Wrap the return type of operation in the provided type.
+     *
+     * @param op The operation to modify.
+     * @param wrapperType The wrapper type.
+     * @param isValidated Whether the wrapper requires validation.
+     * @param isListWrapper Whether the wrapper should be around list items.
+     */
+    private void wrapOperationReturnType(
+            CodegenOperation op, String wrapperType, boolean isValidated, boolean isListWrapper
+    ) {
+        CodegenProperty newReturnType = new CodegenProperty();
+        newReturnType.required = true;
+        newReturnType.isModel = isValidated;
 
-            String typeName = makeSureImported(bodyMapping.mappedBodyType(), op.imports);
+        String typeName = makeSureImported(wrapperType, op.imports);
 
-            if (bodyMapping.isListWrapper) {
-                newProperty.dataType = typeName + '<' + op.returnBaseType + '>';
-                newProperty.items = op.returnProperty.items;
-            } else {
-                newProperty.dataType = typeName + '<' + op.returnType + '>';
-                newProperty.items = op.returnProperty;
+        if (isListWrapper && op.isArray && op.returnProperty.items != null) {
+            newReturnType.dataType = typeName + '<' + op.returnBaseType + '>';
+            newReturnType.items = op.returnProperty.items;
+        } else {
+            String originalReturnType =  op.returnType;
+            if (originalReturnType == null) {
+                originalReturnType = "Void";
+                op.returnProperty = new CodegenProperty();
+                op.returnProperty.dataType = "Void";
             }
+            newReturnType.dataType = typeName + '<' + originalReturnType + '>';
+            newReturnType.items = op.returnProperty;
+        }
+
+        op.returnType = newReturnType.dataType;
+        op.returnContainer = null;
+        op.returnProperty = newReturnType;
+        op.isArray = op.returnProperty.isArray;
+    }
+
+    private void processOperationWithResponseWrappers(CodegenOperation op) {
+        boolean hasNon200StatusCodes = op.responses.stream().anyMatch(
+            response -> !"200".equals(response.code) && response.code.startsWith("2")
+        );
+        boolean hasNonMappedHeaders = !op.responseHeaders.isEmpty();
+        boolean requiresHttpResponse = hasNon200StatusCodes || hasNonMappedHeaders;
+        if (generateHttpResponseAlways || (generateHttpResponseWhereRequired && requiresHttpResponse)) {
+            wrapOperationReturnType(op, "io.micronaut.http.HttpResponse", false, false);
+        }
 
-            op.returnType = newProperty.dataType;
-            op.returnContainer = null;
-            op.returnProperty = newProperty;
+        if (reactive) {
+            wrapOperationReturnType(op, "reactor.core.publisher.Mono", false, false);
         }
     }
 

openapi-generator/src/main/java/io/micronaut/openapi/generator/MicronautCodeGeneratorEntryPoint.java

@@ -126,7 +126,7 @@ private void configureOptions() {
             codeGenerator.addResponseBodyMappings(options.responseBodyMappings);
         }
         codeGenerator.setReactive(options.reactive);
-        codeGenerator.setWrapInHttpResponse(options.wrapInHttpResponse);
+        codeGenerator.setGenerateHttpResponseAlways(options.generateHttpResponseAlways);
         codeGenerator.setUseOptional(options.optional);
         codeGenerator.setUseBeanValidation(options.beanValidation);
         codeGenerator.setTestTool(options.testFramework.value);
@@ -301,7 +301,8 @@ private static class DefaultOptionsBuilder implements MicronautCodeGeneratorOpti
             private List<AbstractMicronautJavaCodegen.ResponseBodyMapping> responseBodyMappings;
             private boolean optional = false;
             private boolean reactive = true;
-            private boolean wrapInHttpResponse;
+            private boolean generateHttpResponseAlways;
+            private boolean generateHttpResponseWhereRequired;
             private TestFramework testFramework = TestFramework.JUNIT5;
             private SerializationLibraryKind serializationLibraryKind = SerializationLibraryKind.MICRONAUT_SERDE_JACKSON;
             private DateTimeFormat dateTimeFormat = DateTimeFormat.ZONED_DATETIME;
@@ -349,8 +350,14 @@ public MicronautCodeGeneratorOptionsBuilder withReactive(boolean reactive) {
             }
 
             @Override
-            public MicronautCodeGeneratorOptionsBuilder withWrapInHttpResponse(boolean wrapInHttpResponse) {
-                this.wrapInHttpResponse = wrapInHttpResponse;
+            public MicronautCodeGeneratorOptionsBuilder withGenerateHttpResponseAlways(boolean generateHttpResponseAlways) {
+                this.generateHttpResponseAlways = generateHttpResponseAlways;
+                return this;
+            }
+
+            @Override
+            public MicronautCodeGeneratorOptionsBuilder withGenerateHttpResponseWhereRequired(boolean generateHttpResponseWhereRequired) {
+                this.generateHttpResponseWhereRequired = generateHttpResponseWhereRequired;
                 return this;
             }
 
@@ -385,7 +392,7 @@ public MicronautCodeGeneratorOptionsBuilder withDateTimeFormat(DateTimeFormat fo
             }
 
             private Options build() {
-                return new Options(apiPackage, modelPackage, invokerPackage, artifactId, parameterMappings, responseBodyMappings, beanValidation, optional, reactive, wrapInHttpResponse, testFramework, serializationLibraryKind, dateTimeFormat);
+                return new Options(apiPackage, modelPackage, invokerPackage, artifactId, parameterMappings, responseBodyMappings, beanValidation, optional, reactive, generateHttpResponseAlways, generateHttpResponseWhereRequired, testFramework, serializationLibraryKind, dateTimeFormat);
             }
         }
     }
@@ -415,7 +422,8 @@ private record Options(
         boolean beanValidation,
         boolean optional,
         boolean reactive,
-        boolean wrapInHttpResponse,
+        boolean generateHttpResponseAlways,
+        boolean generateHttpResponseWhereRequired,
         TestFramework testFramework,
         SerializationLibraryKind serializationLibraryKind,
         MicronautCodeGeneratorOptionsBuilder.DateTimeFormat dateTimeFormat

openapi-generator/src/main/java/io/micronaut/openapi/generator/MicronautCodeGeneratorOptionsBuilder.java

@@ -81,12 +81,20 @@ public interface MicronautCodeGeneratorOptionsBuilder {
     MicronautCodeGeneratorOptionsBuilder withReactive(boolean reactive);
 
     /**
-     * If true, the generated client will use responses wrapped in HttpResponse.
+     * If true, the generated operation return types will be wrapped in HttpResponse.
      *
-     * @param wrapInHttpResponse the wrapping flag
+     * @param generateHttpResponseAlways the wrapping flag
      * @return this builder
      */
-    MicronautCodeGeneratorOptionsBuilder withWrapInHttpResponse(boolean wrapInHttpResponse);
+    MicronautCodeGeneratorOptionsBuilder withGenerateHttpResponseAlways(boolean generateHttpResponseAlways);
+
+    /**
+     * Wrap the operations response in HttpResponse object where non-200 HTTP status codes or additional headers are defined.
+     *
+     * @param generateHttpResponseWhereRequired the wrapping flag
+     * @return this builder
+     */
+    MicronautCodeGeneratorOptionsBuilder withGenerateHttpResponseWhereRequired(boolean generateHttpResponseWhereRequired);
 
     /**
      * If set to true, the generated code will use bean validation.
@@ -134,7 +142,7 @@ public interface MicronautCodeGeneratorOptionsBuilder {
     enum DateTimeFormat {
         OFFSET_DATETIME,
         ZONED_DATETIME,
-        LOCAL_DATETIME;
+        LOCAL_DATETIME
     }
 
 }

openapi-generator/src/main/resources/templates/java-micronaut/client/api.mustache

@@ -67,7 +67,7 @@ public interface {{classname}} {
             {{/authMethods}}
         {{/configureAuth}}
     {{!the method definition}}
-    {{>common/operationReturnType}} {{nickname}}({{#allParams}}
+    {{^returnType}}void{{/returnType}}{{#returnType}}{{{returnType}}}{{/returnType}} {{nickname}}({{#allParams}}
         {{#formatSingleLine}}{{>client/params/queryParams}}{{>client/params/pathParams}}{{>client/params/headerParams}}{{>client/params/bodyParams}}{{>client/params/formParams}}{{>client/params/cookieParams}}{{^-last}},{{/-last}}{{/formatSingleLine}}
     {{/allParams}});
     {{/formatNoEmptyLines}}

openapi-generator/src/main/resources/templates/java-micronaut/server/controller-implementation.mustache

@@ -31,7 +31,7 @@ public class {{controllerClassname}} implements {{classname}} {
     {{#operation}}
     {{!the method definition}}
     @Override
-    public {{>common/operationReturnType}} {{nickname}}({{#allParams}}{{{dataType}}} {{paramName}}{{^-last}}, {{/-last}}{{/allParams}}) {
+    public {{^returnType}}void{{/returnType}}{{#returnType}}{{{returnType}}}{{/returnType}} {{nickname}}({{#allParams}}{{{dataType}}} {{paramName}}{{^-last}}, {{/-last}}{{/allParams}}) {
 {{>server/controllerOperationBody}}    }
     {{^-last}}
 

openapi-generator/src/main/resources/templates/java-micronaut/server/controller-interface.mustache

@@ -73,7 +73,7 @@ public interface {{classname}} {
     @Secured({{openbrace}}{{#vendorExtensions.x-roles}}{{{.}}}{{^-last}}, {{/-last}}{{/vendorExtensions.x-roles}}{{closebrace}})
     {{/useAuth}}
     {{!the method definition}}
-    {{>common/operationReturnType}} {{nickname}}({{#allParams}}
+    {{^returnType}}void{{/returnType}}{{#returnType}}{{{returnType}}}{{/returnType}} {{nickname}}({{#allParams}}
         {{#indent}}
             {{>common/params/validation}}
         {{/indent}}

openapi-generator/src/test/java/io/micronaut/openapi/generator/MicronautServerCodegenTest.java

@@ -211,7 +211,7 @@ void generateAuthRolesWithExtension() {
     void doGenerateMonoWrapHttpResponse() {
         JavaMicronautServerCodegen codegen = new JavaMicronautServerCodegen();
         codegen.additionalProperties().put(JavaMicronautServerCodegen.OPT_REACTIVE, "true");
-        codegen.additionalProperties().put(JavaMicronautServerCodegen.OPT_WRAP_IN_HTTP_RESPONSE, "true");
+        codegen.additionalProperties().put(JavaMicronautServerCodegen.OPT_GENERATE_HTTP_RESPONSE_ALWAYS, "true");
         String outputPath = generateFiles(codegen, PETSTORE_PATH, CodegenConstants.MODELS, CodegenConstants.APIS);
 
         String apiPath = outputPath + "src/main/java/org/openapitools/api/";
@@ -222,7 +222,7 @@ void doGenerateMonoWrapHttpResponse() {
     void doGenerateMono() {
         JavaMicronautServerCodegen codegen = new JavaMicronautServerCodegen();
         codegen.additionalProperties().put(JavaMicronautServerCodegen.OPT_REACTIVE, "true");
-        codegen.additionalProperties().put(JavaMicronautServerCodegen.OPT_WRAP_IN_HTTP_RESPONSE, "false");
+        codegen.additionalProperties().put(JavaMicronautServerCodegen.OPT_GENERATE_HTTP_RESPONSE_ALWAYS, "false");
         String outputPath = generateFiles(codegen, PETSTORE_PATH, CodegenConstants.MODELS, CodegenConstants.APIS);
 
         String apiPath = outputPath + "src/main/java/org/openapitools/api/";
@@ -234,7 +234,7 @@ void doGenerateMono() {
     void doGenerateWrapHttpResponse() {
         JavaMicronautServerCodegen codegen = new JavaMicronautServerCodegen();
         codegen.additionalProperties().put(JavaMicronautServerCodegen.OPT_REACTIVE, "false");
-        codegen.additionalProperties().put(JavaMicronautServerCodegen.OPT_WRAP_IN_HTTP_RESPONSE, "true");
+        codegen.additionalProperties().put(JavaMicronautServerCodegen.OPT_GENERATE_HTTP_RESPONSE_ALWAYS, "true");
         String outputPath = generateFiles(codegen, PETSTORE_PATH, CodegenConstants.MODELS, CodegenConstants.APIS);
 
         String apiPath = outputPath + "src/main/java/org/openapitools/api/";
@@ -246,7 +246,7 @@ void doGenerateWrapHttpResponse() {
     void doGenerateNoMonoNoWrapHttpResponse() {
         JavaMicronautServerCodegen codegen = new JavaMicronautServerCodegen();
         codegen.additionalProperties().put(JavaMicronautServerCodegen.OPT_REACTIVE, "false");
-        codegen.additionalProperties().put(JavaMicronautServerCodegen.OPT_WRAP_IN_HTTP_RESPONSE, "false");
+        codegen.additionalProperties().put(JavaMicronautServerCodegen.OPT_GENERATE_HTTP_RESPONSE_ALWAYS, "false");
         String outputPath = generateFiles(codegen, PETSTORE_PATH, CodegenConstants.MODELS, CodegenConstants.APIS);
 
         String apiPath = outputPath + "src/main/java/org/openapitools/api/";

test-suite-server-generator/build.gradle

@@ -54,6 +54,11 @@ tasks.named("generateOpenApi") {
             // Response with Last-Modified header mapping
             [headerName: "Last-Modified", mappedBodyType: "io.micronaut.openapi.test.dated.DatedResponse"],
             // Response with Page body
-            [headerName: "X-Page-Number", mappedBodyType: "io.micronaut.data.model.Page", isListWrapper: true]
+            [headerName: "X-Page-Number", mappedBodyType: "io.micronaut.data.model.Page", isListWrapper: true],
+            [headerName: "X-Page-Count", mappedBodyType: "io.micronaut.data.model.Page", isListWrapper: true],
+            [headerName: "X-Total-Count", mappedBodyType: "io.micronaut.data.model.Page", isListWrapper: true],
+            [headerName: "X-Page-Size", mappedBodyType: "io.micronaut.data.model.Page", isListWrapper: true],
+            // Ignored header - Does not wrap the response in HttpResponse
+            [headerName: "ignored-header"]
     ]
 }

test-suite-server-generator/spec.yaml

@@ -529,7 +529,7 @@ paths:
       tags: [ responseBody ]
       description: A method to get a simple model as a response
       responses:
-        202:
+        201:
           description: Success
           content:
             application/json: