[kotlin-spring][server] Feat: Return from controllers without ResponseEntity wrapper.

.github/workflows/samples-kotlin-server-jdk17.yaml

@@ -36,6 +36,7 @@ jobs:
           # server
           - samples/server/petstore/kotlin-server-required-and-nullable-properties
           - samples/server/petstore/kotlin-springboot-3
+          - samples/server/petstore/kotlin-springboot-3-no-response-entity
           - samples/server/petstore/kotlin-springboot-additionalproperties
           - samples/server/petstore/kotlin-springboot-delegate-nodefaults
           - samples/server/petstore/kotlin-springboot-request-cookie

.github/workflows/samples-kotlin-server.yaml

@@ -29,6 +29,8 @@ jobs:
         sample:
           # server
           - samples/server/petstore/kotlin-springboot
+          - samples/server/petstore/kotlin-springboot-no-response-entity
+          - samples/server/petstore/kotlin-springboot-no-response-entity-delegate
           - samples/server/petstore/kotlin-springboot-multipart-request-model
           - samples/server/petstore/kotlin-springboot-bigdecimal-default
           - samples/server/petstore/kotlin-springboot-delegate

bin/configs/kotlin-spring-boot-3-no-response-entity.yaml

@@ -0,0 +1,14 @@
+generatorName: kotlin-spring
+outputDir: samples/server/petstore/kotlin-springboot-3-no-response-entity
+library: spring-boot
+inputSpec: modules/openapi-generator/src/test/resources/3_0/petstore.yaml
+templateDir: modules/openapi-generator/src/main/resources/kotlin-spring
+additionalProperties:
+  documentationProvider: none
+  annotationLibrary: none
+  useSwaggerUI: "false"
+  serviceImplementation: "true"
+  serializableModel: "true"
+  beanValidations: "true"
+  useSpringBoot3: "true"
+  requestMappingMode: api_interface

bin/configs/kotlin-spring-boot-no-response-entity-delegate.yaml

@@ -0,0 +1,15 @@
+generatorName: kotlin-spring
+outputDir: samples/server/petstore/kotlin-springboot-no-response-entity-delegate
+library: spring-boot
+inputSpec: modules/openapi-generator/src/test/resources/2_0/petstore.yaml
+templateDir: modules/openapi-generator/src/main/resources/kotlin-spring
+additionalProperties:
+  documentationProvider: none
+  annotationLibrary: none
+  useSwaggerUI: "false"
+  serviceImplementation: "true"
+  serializableModel: "true"
+  beanValidations: "true"
+  useResponseEntity: "false"
+  delegatePattern: true
+  requestMappingMode: controller

bin/configs/kotlin-spring-boot-no-response-entity.yaml

@@ -0,0 +1,14 @@
+generatorName: kotlin-spring
+outputDir: samples/server/petstore/kotlin-springboot-no-response-entity
+library: spring-boot
+inputSpec: modules/openapi-generator/src/test/resources/2_0/petstore.yaml
+templateDir: modules/openapi-generator/src/main/resources/kotlin-spring
+additionalProperties:
+  documentationProvider: none
+  annotationLibrary: none
+  useSwaggerUI: "false"
+  serviceImplementation: "true"
+  serializableModel: "true"
+  beanValidations: "true"
+  useResponseEntity: "false"
+  requestMappingMode: controller

bin/configs/kotlin-spring-declarative-interface-reactive-coroutines.yaml

@@ -11,6 +11,6 @@ additionalProperties:
   beanValidations: "true"
   interfaceOnly: true
   reactive: true
-  declarativeInterfaceWrapResponses: false
+  useResponseEntity: false
   useFlowForArrayReturnType: false
   declarativeInterfaceReactiveMode: "coroutines"

bin/configs/kotlin-spring-declarative-interface-reactive-reactor-wrapped.yaml

@@ -11,6 +11,6 @@ additionalProperties:
   beanValidations: "true"
   interfaceOnly: true
   reactive: true
-  declarativeInterfaceWrapResponses: true
+  useResponseEntity: true
   useFlowForArrayReturnType: false
   declarativeInterfaceReactiveMode: "reactor"

bin/configs/kotlin-spring-declarative-interface-wrapped.yaml

@@ -11,5 +11,5 @@ additionalProperties:
   beanValidations: "true"
   interfaceOnly: true
   reactive: false
-  declarativeInterfaceWrapResponses: true
+  useResponseEntity: true
   useFlowForArrayReturnType: false

bin/configs/kotlin-spring-declarative-interface.yaml

@@ -11,5 +11,5 @@ additionalProperties:
   beanValidations: "true"
   interfaceOnly: true
   reactive: false
-  declarativeInterfaceWrapResponses: true
+  useResponseEntity: true
   useFlowForArrayReturnType: false

docs/generators/kotlin-spring.md

@@ -28,7 +28,6 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 |beanQualifiers|Whether to add fully-qualifier class names as bean qualifiers in @Component and @RestController annotations. May be used to prevent bean names clash if multiple generated libraries (contexts) added to single project.| |false|
 |configPackage|configuration package for generated code| |org.openapitools.configuration|
 |declarativeInterfaceReactiveMode|What type of reactive style to use in Spring Http declarative interface|<dl><dt>**coroutines**</dt><dd>Use kotlin-idiomatic 'suspend' functions</dd><dt>**reactor**</dt><dd>Use reactor return wrappers 'Mono' and 'Flux'</dd></dl>|coroutines|
-|declarativeInterfaceWrapResponses|Whether (when false) to return actual type (e.g. List&lt;Fruit&gt;) and handle non 2xx responses via exceptions or (when true) return entire ResponseEntity (e.g. ResponseEntity&lt;List&lt;Fruit&gt;&gt;)| |false|
 |delegatePattern|Whether to generate the server files using the delegate pattern| |false|
 |documentationProvider|Select the OpenAPI documentation provider.|<dl><dt>**none**</dt><dd>Do not publish an OpenAPI specification.</dd><dt>**source**</dt><dd>Publish the original input OpenAPI specification.</dd><dt>**springfox**</dt><dd>Generate an OpenAPI 2 (fka Swagger RESTful API Documentation Specification) specification using SpringFox 2.x. Deprecated (for removal); use springdoc instead.</dd><dt>**springdoc**</dt><dd>Generate an OpenAPI 3 specification using SpringDoc.</dd></dl>|springdoc|
 |enumPropertyNaming|Naming convention for enum properties: 'camelCase', 'PascalCase', 'snake_case', 'UPPERCASE', and 'original'| |original|
@@ -56,6 +55,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 |useBeanValidation|Use BeanValidation API annotations to validate data types| |true|
 |useFeignClientUrl|Whether to generate Feign client with url parameter.| |true|
 |useFlowForArrayReturnType|Whether to use Flow for array/collection return types when reactive is enabled. If false, will use List instead.| |true|
+|useResponseEntity|Whether (when false) to return actual type (e.g. List&lt;Fruit&gt;) and handle non-happy path responses via exceptions flow or (when true) return entire ResponseEntity (e.g. ResponseEntity&lt;List&lt;Fruit&gt;&gt;). If disabled, method are annotated using a @ResponseStatus annotation, which has the status of the first response declared in the Api definition| |true|
 |useSpringBoot3|Generate code and provide dependencies for use with Spring Boot 3.x. (Use jakarta instead of javax in imports). Enabling this option will also enable `useJakartaEe`.| |false|
 |useSwaggerUI|Open the OpenApi specification in swagger-ui. Will also import and configure needed dependencies| |true|
 |useTags|Whether to use tags for creating interface and controller class names| |false|

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

@@ -33,6 +33,7 @@
 import org.openapitools.codegen.model.ModelsMap;
 import org.openapitools.codegen.model.OperationMap;
 import org.openapitools.codegen.model.OperationsMap;
+import org.openapitools.codegen.templating.mustache.SpringHttpStatusLambda;
 import org.openapitools.codegen.utils.ModelUtils;
 import org.openapitools.codegen.utils.URLPathUtils;
 import org.slf4j.Logger;
@@ -85,7 +86,7 @@ public class KotlinSpringServerCodegen extends AbstractKotlinCodegen
     public static final String DELEGATE_PATTERN = "delegatePattern";
     public static final String USE_TAGS = "useTags";
     public static final String BEAN_QUALIFIERS = "beanQualifiers";
-    public static final String DECLARATIVE_INTERFACE_WRAP_RESPONSES = "declarativeInterfaceWrapResponses";
+    public static final String USE_RESPONSE_ENTITY = "useResponseEntity";
     public static final String DECLARATIVE_INTERFACE_REACTIVE_MODE = "declarativeInterfaceReactiveMode";
 
     public static final String USE_SPRING_BOOT3 = "useSpringBoot3";
@@ -109,6 +110,7 @@ public enum DeclarativeInterfaceReactiveMode {
         }
     }
 
+
     public enum RequestMappingMode {
         api_interface("Generate the @RequestMapping annotation on the generated Api Interface."),
         controller("Generate the @RequestMapping annotation on the generated Api Controller Implementation."),
@@ -155,7 +157,7 @@ public String getDescription() {
     @Setter protected boolean useTags = false;
     @Setter private boolean beanQualifiers = false;
     @Setter private DeclarativeInterfaceReactiveMode declarativeInterfaceReactiveMode = DeclarativeInterfaceReactiveMode.coroutines;
-    @Setter private boolean declarativeInterfaceWrapResponses = false;
+    @Setter private boolean useResponseEntity = true;
 
     @Getter @Setter
     protected boolean useSpringBoot3 = false;
@@ -242,9 +244,9 @@ public KotlinSpringServerCodegen() {
         addSwitch(USE_SPRING_BOOT3, "Generate code and provide dependencies for use with Spring Boot 3.x. (Use jakarta instead of javax in imports). Enabling this option will also enable `useJakartaEe`.", useSpringBoot3);
         addSwitch(USE_FLOW_FOR_ARRAY_RETURN_TYPE, "Whether to use Flow for array/collection return types when reactive is enabled. If false, will use List instead.", useFlowForArrayReturnType);
         addSwitch(INCLUDE_HTTP_REQUEST_CONTEXT, "Whether to include HttpServletRequest (blocking) or ServerWebExchange (reactive) as additional parameter in generated methods.", includeHttpRequestContext);
-        addSwitch(DECLARATIVE_INTERFACE_WRAP_RESPONSES,
-                "Whether (when false) to return actual type (e.g. List<Fruit>) and handle non 2xx responses via exceptions or (when true) return entire ResponseEntity (e.g. ResponseEntity<List<Fruit>>)",
-                declarativeInterfaceWrapResponses);
+        addSwitch(USE_RESPONSE_ENTITY,
+                "Whether (when false) to return actual type (e.g. List<Fruit>) and handle non-happy path responses via exceptions flow or (when true) return entire ResponseEntity (e.g. ResponseEntity<List<Fruit>>). If disabled, method are annotated using a @ResponseStatus annotation, which has the status of the first response declared in the Api definition",
+                useResponseEntity);
         supportedLibraries.put(SPRING_BOOT, "Spring-boot Server application.");
         supportedLibraries.put(SPRING_CLOUD_LIBRARY,
                 "Spring-Cloud-Feign client with Spring-Boot auto-configured settings.");
@@ -468,6 +470,12 @@ public void processOpts() {
             additionalProperties.put(CodegenConstants.LIBRARY, library);
         }
 
+        if(additionalProperties.containsKey(USE_RESPONSE_ENTITY)) {
+            this.setUseResponseEntity(Boolean.parseBoolean(additionalProperties.get(USE_RESPONSE_ENTITY).toString()));
+        }
+        writePropertyBack(USE_RESPONSE_ENTITY, useResponseEntity);
+        additionalProperties.put("springHttpStatus", new SpringHttpStatusLambda());
+
         // Set basePackage from invokerPackage
         if (!additionalProperties.containsKey(BASE_PACKAGE)
                 && additionalProperties.containsKey(CodegenConstants.INVOKER_PACKAGE)) {

modules/openapi-generator/src/main/resources/kotlin-spring/api.mustache

@@ -20,14 +20,19 @@ import io.swagger.annotations.AuthorizationScope
 {{/swagger1AnnotationLibrary}}
 import org.springframework.http.HttpStatus
 import org.springframework.http.MediaType
+{{#useResponseEntity}}
 import org.springframework.http.ResponseEntity
+{{/useResponseEntity}}
 
 import org.springframework.web.bind.annotation.*
 {{#useBeanValidation}}
 import org.springframework.validation.annotation.Validated
 {{/useBeanValidation}}
 import org.springframework.web.context.request.NativeWebRequest
 import org.springframework.beans.factory.annotation.Autowired
+{{#useRequestMappingOnController}}
+import {{#apiPackage}}{{.}}.{{/apiPackage}}{{classname}}Controller.Companion.BASE_PATH
+{{/useRequestMappingOnController}}
 
 {{#useBeanValidation}}
 import {{javaxPackage}}.validation.Valid
@@ -56,15 +61,18 @@ import kotlin.collections.Map
 {{/swagger1AnnotationLibrary}}
 {{#useRequestMappingOnController}}
 {{=<% %>=}}
-@RequestMapping("\${api.base-path:<%contextPath%>}")
+@RequestMapping("\${api.<%title%>.base-path:api.base-path:$BASE_PATH}")
 <%={{ }}=%>
 {{/useRequestMappingOnController}}
 {{#operations}}
 class {{classname}}Controller({{#serviceInterface}}@Autowired(required = true) val service: {{classname}}Service{{/serviceInterface}}) {
-{{#operation}}
 
-    {{#swagger2AnnotationLibrary}}
-    @Operation(
+{{#operation}}
+{{^useResponseEntity}}
+    @ResponseStatus({{#springHttpStatus}}{{#responses.0}}{{{code}}}{{/responses.0}}{{/springHttpStatus}}){{!
+}}{{/useResponseEntity}}{{!
+}}{{#swagger2AnnotationLibrary}}{{!
+}}    @Operation(
         summary = "{{{summary}}}",
         operationId = "{{{operationId}}}",
         description = """{{{unescapedNotes}}}""",
@@ -83,15 +91,28 @@ class {{classname}}Controller({{#serviceInterface}}@Autowired(required = true) v
         value = [{{#responses}}ApiResponse(code = {{{code}}}, message = "{{{message}}}"{{#baseType}}, response = {{{.}}}::class{{/baseType}}{{#containerType}}, responseContainer = "{{{.}}}"{{/containerType}}){{^-last}},{{/-last}}{{/responses}}]){{/swagger1AnnotationLibrary}}
     @RequestMapping(
         method = [RequestMethod.{{httpMethod}}],
-        value = ["{{#lambdaEscapeInNormalString}}{{{path}}}{{/lambdaEscapeInNormalString}}"]{{#singleContentTypes}}{{#hasProduces}},
+        value = [PATH_{{#lambda.uppercase}}{{#lambda.snakecase}}{{{operationId}}}{{/lambda.snakecase}}{{/lambda.uppercase}} /* "{{#lambdaEscapeInNormalString}}{{{path}}}{{/lambdaEscapeInNormalString}}" */]{{#singleContentTypes}}{{#hasProduces}},
         produces = [{{#vendorExtensions.x-accepts}}"{{{.}}}"{{^-last}}, {{/-last}}{{/vendorExtensions.x-accepts}}]{{/hasProduces}}{{#hasConsumes}},
         consumes = "{{{vendorExtensions.x-content-type}}}"{{/hasConsumes}}{{/singleContentTypes}}{{^singleContentTypes}}{{#hasProduces}},
         produces = [{{#produces}}"{{{mediaType}}}"{{^-last}}, {{/-last}}{{/produces}}]{{/hasProduces}}{{#hasConsumes}},
         consumes = [{{#consumes}}"{{{mediaType}}}"{{^-last}}, {{/-last}}{{/consumes}}]{{/hasConsumes}}{{/singleContentTypes}}
     )
-    {{#reactive}}{{^isArray}}suspend {{/isArray}}{{#isArray}}{{^useFlowForArrayReturnType}}suspend {{/useFlowForArrayReturnType}}{{/isArray}}{{/reactive}}fun {{operationId}}({{#allParams}}{{>queryParams}}{{>pathParams}}{{>headerParams}}{{>cookieParams}}{{>bodyParams}}{{>formParams}}{{^-last}},{{/-last}}{{/allParams}}{{#includeHttpRequestContext}}{{#hasParams}}, {{/hasParams}}{{#swagger1AnnotationLibrary}}@ApiParam(hidden = true) {{/swagger1AnnotationLibrary}}{{#swagger2AnnotationLibrary}}@Parameter(hidden = true) {{/swagger2AnnotationLibrary}}{{#reactive}}exchange: org.springframework.web.server.ServerWebExchange{{/reactive}}{{^reactive}}request: {{javaxPackage}}.servlet.http.HttpServletRequest{{/reactive}}{{/includeHttpRequestContext}}): ResponseEntity<{{>returnTypes}}> {
+    {{#reactive}}{{^isArray}}suspend {{/isArray}}{{#isArray}}{{^useFlowForArrayReturnType}}suspend {{/useFlowForArrayReturnType}}{{/isArray}}{{/reactive}}fun {{operationId}}({{#allParams}}
+        {{>queryParams}}{{>pathParams}}{{>headerParams}}{{>cookieParams}}{{>bodyParams}}{{>formParams}}{{^-last}},{{/-last}}{{/allParams}}{{#includeHttpRequestContext}}{{#hasParams}},
+        {{/hasParams}}{{#swagger1AnnotationLibrary}}@ApiParam(hidden = true) {{/swagger1AnnotationLibrary}}{{#swagger2AnnotationLibrary}}@Parameter(hidden = true) {{/swagger2AnnotationLibrary}}{{#reactive}}exchange: org.springframework.web.server.ServerWebExchange{{/reactive}}{{^reactive}}request: {{javaxPackage}}.servlet.http.HttpServletRequest{{/reactive}}{{/includeHttpRequestContext}}{{#hasParams}}
+    {{/hasParams}}): {{#useResponseEntity}}ResponseEntity<{{/useResponseEntity}}{{>returnTypes}}{{#useResponseEntity}}>{{/useResponseEntity}} {
         return {{>returnValue}}
     }
+
 {{/operation}}
+    companion object {
+        //for your own safety never directly reuse these path definitions in tests
+    {{#useRequestMappingOnController}}
+        const val BASE_PATH: String = "{{=<% %>=}}<%contextPath%><%={{ }}=%>"
+    {{/useRequestMappingOnController}}
+    {{#operation}}
+        const val PATH_{{#lambda.uppercase}}{{#lambda.snakecase}}{{{operationId}}}{{/lambda.snakecase}}{{/lambda.uppercase}}: String = "{{{path}}}"
+    {{/operation}}
+    }
 }
 {{/operations}}

modules/openapi-generator/src/main/resources/kotlin-spring/apiDelegate.mustache

@@ -4,7 +4,9 @@ package {{package}}
 {{/imports}}
 import org.springframework.http.HttpStatus
 import org.springframework.http.MediaType
+{{#useResponseEntity}}
 import org.springframework.http.ResponseEntity
+{{/useResponseEntity}}
 import org.springframework.web.context.request.NativeWebRequest
 {{#appendRequestToHandler}}
 import org.springframework.http.server.reactive.ServerHttpRequest
@@ -14,9 +16,6 @@ import kotlinx.coroutines.flow.Flow
 {{/reactive}}
 
 import java.util.Optional
-{{#async}}
-import java.util.concurrent.CompletableFuture
-{{/async}}
 
 {{#operations}}
 /**
@@ -35,7 +34,7 @@ interface {{classname}}Delegate {
      */
     {{#reactive}}{{^isArray}}suspend {{/isArray}}{{#isArray}}{{^useFlowForArrayReturnType}}suspend {{/useFlowForArrayReturnType}}{{/isArray}}{{/reactive}}fun {{operationId}}({{#allParams}}{{{paramName}}}: {{^reactive}}{{>optionalDataType}}{{/reactive}}{{#reactive}}{{^isArray}}{{>optionalDataType}}{{/isArray}}{{#isArray}}{{#isBodyParam}}Flow<{{{baseType}}}>{{/isBodyParam}}{{^isBodyParam}}{{>optionalDataType}}{{/isBodyParam}}{{/isArray}}{{/reactive}}{{^-last}},
         {{/-last}}{{/allParams}}{{#includeHttpRequestContext}}{{#hasParams}},
-        {{/hasParams}}{{#reactive}}exchange: org.springframework.web.server.ServerWebExchange{{/reactive}}{{^reactive}}request: {{javaxPackage}}.servlet.http.HttpServletRequest{{/reactive}}{{/includeHttpRequestContext}}): {{#responseWrapper}}{{.}}<{{/responseWrapper}}ResponseEntity<{{>returnTypes}}>{{#responseWrapper}}>{{/responseWrapper}}{{^skipDefaultDelegateInterface}} {
+        {{/hasParams}}{{#reactive}}exchange: org.springframework.web.server.ServerWebExchange{{/reactive}}{{^reactive}}request: {{javaxPackage}}.servlet.http.HttpServletRequest{{/reactive}}{{/includeHttpRequestContext}}): {{#useResponseEntity}}ResponseEntity<{{/useResponseEntity}}{{>returnTypes}}{{#useResponseEntity}}>{{/useResponseEntity}}{{^skipDefaultDelegateInterface}} {
         {{>methodBody}}{{! prevent indent}}
     }{{/skipDefaultDelegateInterface}}