add omitGradleWrapper option to kotlin-server code generator (#16528)

The added option removes the wrapper part of build.gradle, enabling the generated project to be used as a sub project. The same option from kotlin client was used as reference for this change.

docs/generators/kotlin-server.md

@@ -34,6 +34,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 |interfaceOnly|Whether to generate only API interface stubs without the server files. This option is currently supported only when using jaxrs-spec library.| |false|
 |library|library template (sub-template)|<dl><dt>**ktor**</dt><dd>ktor framework</dd><dt>**jaxrs-spec**</dt><dd>JAX-RS spec only</dd></dl>|ktor|
 |modelMutable|Create mutable models| |false|
+|omitGradleWrapper|Whether to omit Gradle wrapper for creating a sub project.| |false|
 |packageName|Generated artifact package name.| |org.openapitools.server|
 |parcelizeModels|toggle &quot;@Parcelize&quot; for generated models| |null|
 |returnResponse|Whether generate API interface should return javax.ws.rs.core.Response instead of a deserialized entity. Only useful if interfaceOnly is true. This option is currently supported only when using jaxrs-spec library.| |false|

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

@@ -50,6 +50,7 @@ public class KotlinServerCodegen extends AbstractKotlinCodegen implements BeanVa
     private boolean useCoroutines = false;
     private boolean useMutiny = false;
     private boolean returnResponse = false;
+    private boolean omitGradleWrapper = false;
 
     // This is here to potentially warn the user when an option is not supported by the target framework.
     private Map<String, List<String>> optionsSupportedPerFramework = new ImmutableMap.Builder<String, List<String>>()
@@ -60,7 +61,8 @@ public class KotlinServerCodegen extends AbstractKotlinCodegen implements BeanVa
                     Constants.CORS,
                     Constants.COMPRESSION,
                     Constants.RESOURCES,
-                    Constants.METRICS
+                    Constants.METRICS,
+                    Constants.OMIT_GRADLE_WRAPPER
             ))
             .put(Constants.JAXRS_SPEC, Arrays.asList(
                     USE_BEANVALIDATION,
@@ -132,6 +134,7 @@ public class KotlinServerCodegen extends AbstractKotlinCodegen implements BeanVa
         addSwitch(Constants.USE_COROUTINES, Constants.USE_COROUTINES_DESC, useCoroutines);
         addSwitch(Constants.USE_MUTINY, Constants.USE_MUTINY_DESC, useMutiny);
         addSwitch(Constants.RETURN_RESPONSE, Constants.RETURN_RESPONSE_DESC, returnResponse);
+        addSwitch(Constants.OMIT_GRADLE_WRAPPER, Constants.OMIT_GRADLE_WRAPPER_DESC, omitGradleWrapper);
         addSwitch(USE_JAKARTA_EE, Constants.USE_JAKARTA_EE_DESC, useJakartaEe);
     }
 
@@ -183,6 +186,14 @@ public class KotlinServerCodegen extends AbstractKotlinCodegen implements BeanVa
         return resourcesFeatureEnabled;
     }
 
+    public boolean getOmitGradleWrapper() {
+        return omitGradleWrapper;
+    }
+
+    public void setOmitGradleWrapper(boolean omitGradleWrapper) {
+        this.omitGradleWrapper = omitGradleWrapper;
+    }
+
     public void setResourcesFeatureEnabled(Boolean resourcesFeatureEnabled) {
         this.resourcesFeatureEnabled = resourcesFeatureEnabled;
     }
@@ -247,6 +258,10 @@ public class KotlinServerCodegen extends AbstractKotlinCodegen implements BeanVa
             setUseBeanValidation(convertPropertyToBoolean(USE_BEANVALIDATION));
         }
 
+        if (additionalProperties.containsKey(Constants.OMIT_GRADLE_WRAPPER)) {
+            setOmitGradleWrapper(Boolean.parseBoolean(additionalProperties.get(Constants.OMIT_GRADLE_WRAPPER).toString()));
+        }
+
         writePropertyBack(USE_BEANVALIDATION, useBeanValidation);
 
         // set default library to "ktor"
@@ -360,6 +375,8 @@ public class KotlinServerCodegen extends AbstractKotlinCodegen implements BeanVa
         public static final String USE_JAKARTA_EE_DESC = "whether to use Jakarta EE namespace instead of javax";
         public static final String USE_MUTINY = "useMutiny";
         public static final String USE_MUTINY_DESC = "Whether to use Mutiny (should not be used with useCoroutines). This option is currently supported only when using jaxrs-spec library.";
+        public static final String OMIT_GRADLE_WRAPPER = "omitGradleWrapper";
+        public static final String OMIT_GRADLE_WRAPPER_DESC = "Whether to omit Gradle wrapper for creating a sub project.";
     }
 
     @Override

modules/openapi-generator/src/main/resources/kotlin-server/libraries/jaxrs-spec/build.gradle.mustache

@@ -2,7 +2,7 @@ group "{{groupId}}"
 version "{{artifactVersion}}"
 
 wrapper {
-    gradleVersion = "6.9"
+    gradleVersion = '6.9'
     distributionUrl = "https://services.gradle.org/distributions/gradle-$gradleVersion-all.zip"
 }
 
@@ -67,4 +67,4 @@ dependencies {
     implementation("io.smallrye.reactive:mutiny-kotlin:$mutiny_version")
 {{/useMutiny}}
     testImplementation("junit:junit:4.13.2")
-}
+}

modules/openapi-generator/src/main/resources/kotlin-server/libraries/ktor/build.gradle.mustache

@@ -1,10 +1,12 @@
 group "{{groupId}}"
 version "{{artifactVersion}}"
+{{^omitGradleWrapper}}
 
 wrapper {
     gradleVersion = "7.4.2"
     distributionUrl = "https://services.gradle.org/distributions/gradle-$gradleVersion-all.zip"
 }
+{{/omitGradleWrapper}}
 
 buildscript {
     ext.kotlin_version = "1.7.20"

samples/server/petstore/kotlin-server/ktor/build.gradle

@@ -2,7 +2,7 @@ group "org.openapitools"
 version "1.0.0"
 
 wrapper {
-    gradleVersion = "7.4.2"
+    gradleVersion = '7.5'
     distributionUrl = "https://services.gradle.org/distributions/gradle-$gradleVersion-all.zip"
 }