New feature: OpenAPI generator for kotlin (micronaut-projects#1254)

Adds a new OpenAPI generator implementation for Kotlin

Fixes micronaut-projects#1239

.editorconfig

@@ -6,6 +6,9 @@ insert_final_newline = true
 charset = utf-8
 indent_style = space
 
+[{*.mustache,*.ftl}]
+insert_final_newline = false
+
 [{*.sh,gradlew}]
 end_of_line = lf
 

build-logic/src/main/groovy/io.micronaut.build.internal.openapi-generator-test-suite.gradle → build-logic/src/main/groovy/io.micronaut.build.internal.openapi-java-generator-test-suite.gradle

@@ -20,6 +20,7 @@ dependencies {
 }
 
 def openapiGenerate = tasks.register("generateOpenApi", OpenApiGeneratorTask) {
+    lang = "java"
     classpath.from(configurations.openapiGenerator)
     openApiDefinition.convention(layout.projectDirectory.file("petstore.json"))
     outputDirectory.convention(layout.buildDirectory.dir("generated/openapi"))

build-logic/src/main/groovy/io.micronaut.build.internal.openapi-kotlin-generator-test-suite.gradle

@@ -0,0 +1,52 @@
+import io.micronaut.build.internal.openapi.OpenApiGeneratorTask
+
+plugins {
+    id 'io.micronaut.minimal.application'
+}
+
+repositories {
+    mavenCentral()
+}
+
+configurations {
+    openapiGenerator {
+        canBeResolved = true
+        canBeConsumed = false
+    }
+}
+
+dependencies {
+    openapiGenerator(project(":test-suite-generator-util"))
+}
+
+def openapiGenerate = tasks.register("generateOpenApi", OpenApiGeneratorTask) {
+    lang = "kotlin"
+    classpath.from(configurations.openapiGenerator)
+    openApiDefinition.convention(layout.projectDirectory.file("petstore.json"))
+    outputDirectory.convention(layout.buildDirectory.dir("generated/openapi"))
+    generatorKind.convention("client")
+    outputKinds.convention(["models", "apis", "apiDocs", "modelDocs", "supportingFiles", "modelTests", "apiTests"])
+    parameterMappings.convention([])
+    responseBodyMappings.convention([])
+}
+
+sourceSets {
+    main {
+        java.srcDir(openapiGenerate.map(OpenApiGeneratorTask::getGeneratedSourcesDirectory))
+    }
+    test {
+        java.srcDir(openapiGenerate.map(OpenApiGeneratorTask::getGeneratedTestSourcesDirectory))
+    }
+}
+
+micronaut {
+    version = libs.versions.micronaut.platform.get()
+    runtime("netty")
+    testRuntime("junit5")
+}
+
+dependencies {
+    constraints {
+        implementation("io.micronaut:micronaut-http-client:${libs.versions.micronaut.asProvider().get()}")
+    }
+}

build-logic/src/main/groovy/io/micronaut/build/internal/openapi/OpenApiGeneratorTask.java

@@ -15,6 +15,13 @@
  */
 package io.micronaut.build.internal.openapi;
 
+import java.io.IOException;
+import java.nio.file.Files;
+import java.util.ArrayList;
+import java.util.Map;
+
+import javax.inject.Inject;
+
 import org.gradle.api.DefaultTask;
 import org.gradle.api.file.ConfigurableFileCollection;
 import org.gradle.api.file.Directory;
@@ -33,13 +40,6 @@
 import org.gradle.api.tasks.TaskAction;
 import org.gradle.process.ExecOperations;
 
-import javax.inject.Inject;
-import java.io.IOException;
-import java.nio.file.Files;
-import java.util.ArrayList;
-import java.util.List;
-import java.util.Map;
-
 /**
  * A task which simulates what the Gradle Micronaut plugin
  * would do. Must be used with the test entry point.
@@ -55,17 +55,22 @@ public abstract class OpenApiGeneratorTask extends DefaultTask {
     @Input
     public abstract Property<String> getGeneratorKind();
 
+    @Input
+    public abstract Property<String> getLang();
+
     @OutputDirectory
     public abstract DirectoryProperty getOutputDirectory();
 
     @Internal
     public Provider<Directory> getGeneratedSourcesDirectory() {
-        return getOutputDirectory().dir("src/main/java");
+        String lang = getLang().get();
+        return lang.equalsIgnoreCase("JAVA") ? getOutputDirectory().dir("src/main/java") : getOutputDirectory().dir("src/main/kotlin");
     }
 
     @Internal
     public Provider<Directory> getGeneratedTestSourcesDirectory() {
-        return getOutputDirectory().dir("src/test/groovy");
+        String lang = getLang().get();
+        return lang.equalsIgnoreCase("JAVA") ? getOutputDirectory().dir("src/test/groovy") : getOutputDirectory().dir("src/test/kotlin");
     }
 
     @Input
@@ -77,27 +82,28 @@ public Provider<Directory> getGeneratedTestSourcesDirectory() {
     @Input
     public abstract ListProperty<Map<String, String>> getResponseBodyMappings();
 
-
     @Inject
     protected abstract ExecOperations getExecOperations();
 
     @TaskAction
     public void execute() throws IOException {
         var generatedSourcesDir = getGeneratedSourcesDirectory().get().getAsFile();
         var generatedTestSourcesDir = getGeneratedTestSourcesDirectory().get().getAsFile();
+        var lang = getLang().get();
         Files.createDirectories(generatedSourcesDir.toPath());
         Files.createDirectories(generatedTestSourcesDir.toPath());
-        getProject().getLogger().info("json: " + getParameterMappings().get());
+        getProject().getLogger().info("json: {}", getParameterMappings().get());
         getExecOperations().javaexec(javaexec -> {
             javaexec.setClasspath(getClasspath());
             javaexec.getMainClass().set("io.micronaut.openapi.testsuite.GeneratorMain");
-            List<String> args = new ArrayList<>();
+            var args = new ArrayList<String>();
             args.add(getGeneratorKind().get());
             args.add(getOpenApiDefinition().get().getAsFile().toURI().toString());
             args.add(getOutputDirectory().get().getAsFile().getAbsolutePath());
             args.add(String.join(",", getOutputKinds().get()));
             args.add(getParameterMappings().get().toString());
             args.add(getResponseBodyMappings().get().toString());
+            args.add(lang.toUpperCase());
             javaexec.args(args);
         });
     }

gradle/libs.versions.toml

@@ -7,7 +7,7 @@ managed-parboiled = "1.4.1"
 managed-freemarker = "2.3.32"
 managed-pegdown = "1.6.0"
 
-kotlin = "1.9.10"
+kotlin = "1.9.20"
 jspecify = "0.3.0"
 jdt-annotation = "2.2.700"
 android-annotation = "1.7.0"
@@ -18,7 +18,7 @@ swagger-parser-v3 = "2.1.18"
 javaparser = "3.25.5"
 commons-codec = "1.16.0"
 
-micronaut = "4.1.10"
+micronaut = "4.1.11"
 micronaut-security = "4.1.0"
 micronaut-serde = "2.2.6"
 micronaut-rxjava2 = "2.0.1"
@@ -61,6 +61,7 @@ managed-pegdown = {module = "org.pegdown:pegdown", version.ref = "managed-pegdow
 
 # Versions from BOM
 junit-jupiter-engine = { module = "org.junit.jupiter:junit-jupiter-engine" }
+junit-jupiter-params = { module = "org.junit.jupiter:junit-jupiter-params" }
 jackson-datatype-jsr310 = { module = "com.fasterxml.jackson.datatype:jackson-datatype-jsr310" }
 jackson-dataformat-yaml = { module = "com.fasterxml.jackson.dataformat:jackson-dataformat-yaml" }
 kotlinx-coroutines-reactor = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-reactor" }

openapi-common/src/main/java/io/micronaut/openapi/swagger/core/jackson/mixin/OpenAPIMixin.java

@@ -24,6 +24,7 @@
 import com.fasterxml.jackson.annotation.JsonAnyGetter;
 import com.fasterxml.jackson.annotation.JsonAnySetter;
 import com.fasterxml.jackson.annotation.JsonIgnore;
+import com.fasterxml.jackson.annotation.JsonInclude;
 import com.fasterxml.jackson.databind.annotation.JsonSerialize;
 
 /**
@@ -34,6 +35,7 @@
 public abstract class OpenAPIMixin {
 
     @JsonAnyGetter
+    @JsonInclude
     public abstract Map<String, Object> getExtensions();
 
     @JsonAnySetter

openapi-generator/build.gradle

@@ -15,6 +15,7 @@ dependencies {
     implementation libs.commons.codec
 
     testImplementation mnTest.micronaut.test.junit5
+    testImplementation libs.junit.jupiter.params
 
     testFixturesImplementation mnTest.assertj.core
     testFixturesImplementation libs.javaparser