[Kotlin Server] Update Ktor to the next major version 3 (#20245)

* [Kotlin Server] Update Ktor to version 3

* [Kotlin Server] Clean up

* [Kotlin Server] Fix problems

* [Kotlin Server] Fix Ktor and modelMutable samples

* [Kotlin Server] Fix the string value for serialization key

* [Kotlin Server] Remove setting Kotlin serialization flag to true

* [Kotlin Server] Remove setting Kotlin serialization flag to true

* [Kotlin Server] Remove the option to enable Kotlin serialization

* [Kotlin Server] Use query parameters

Author: Stexxe

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

@@ -236,6 +236,11 @@ public void processOpts() {
             LOGGER.info("`library` option is empty. Default to {}", DEFAULT_LIBRARY);
         }
 
+        if (isKtor()) {
+            typeMapping.put("date-time", "kotlin.String");
+            typeMapping.put("DateTime", "kotlin.String");
+        }
+
         if (additionalProperties.containsKey(Constants.AUTOMATIC_HEAD_REQUESTS)) {
             setAutoHeadFeatureEnabled(convertPropertyToBooleanAndWriteBack(Constants.AUTOMATIC_HEAD_REQUESTS));
         } else {
@@ -298,6 +303,8 @@ public void processOpts() {
         supportingFiles.add(new SupportingFile("gradle.properties", "", "gradle.properties"));
 
         if (isKtor()) {
+            additionalProperties.put(Constants.IS_KTOR, true);
+
             supportingFiles.add(new SupportingFile("AppMain.kt.mustache", packageFolder, "AppMain.kt"));
             supportingFiles.add(new SupportingFile("Configuration.kt.mustache", packageFolder, "Configuration.kt"));
 
@@ -365,6 +372,7 @@ public static class Constants {
         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.";
+        public static final String IS_KTOR = "isKtor";
     }
 
     @Override
@@ -386,6 +394,13 @@ public OperationsMap postProcessOperationsWithModels(OperationsMap objs, List<Mo
         if (operations != null && !Objects.equals(library, Constants.JAXRS_SPEC)) {
             List<CodegenOperation> ops = operations.getOperation();
             ops.forEach(operation -> {
+                if (isKtor()) {
+                    ArrayList<CodegenParameter> params = new ArrayList<>();
+                    params.addAll(operation.pathParams);
+                    params.addAll(operation.queryParams);
+                    operation.vendorExtensions.put("ktor-params", params);
+                }
+
                 List<CodegenResponse> responses = operation.responses;
                 if (responses != null) {
                     responses.forEach(resp -> {

modules/openapi-generator/src/main/resources/kotlin-server/data_class.mustache

@@ -1,11 +1,15 @@
-{{#parcelizeModels}}
+{{#isKtor}}
+import kotlinx.serialization.Serializable
+{{/isKtor}}
+{{^isKtor}}
+    {{#parcelizeModels}}
 import android.os.Parcelable
 import kotlinx.parcelize.Parcelize
-
-{{/parcelizeModels}}
-{{#serializableModel}}
+    {{/parcelizeModels}}
+    {{#serializableModel}}
 import java.io.Serializable
-{{/serializableModel}}
+    {{/serializableModel}}
+{{/isKtor}}
 /**
  * {{{description}}}
 {{#vars}}
@@ -15,21 +19,19 @@ import java.io.Serializable
 {{#parcelizeModels}}
 @Parcelize
 {{/parcelizeModels}}
+{{#isKtor}}
+@Serializable
+{{/isKtor}}
 {{#hasVars}}data {{/hasVars}}class {{classname}}(
 {{#requiredVars}}
 {{>data_class_req_var}}{{^-last}},
 {{/-last}}{{/requiredVars}}{{#hasRequired}}{{#hasOptional}},
 {{/hasOptional}}{{/hasRequired}}{{#optionalVars}}{{>data_class_opt_var}}{{^-last}},
 {{/-last}}{{/optionalVars}}
-) {{^serializableModel}}{{#parcelizeModels}} : Parcelable{{/parcelizeModels}}{{/serializableModel}}{{^parcelizeModels}}{{#serializableModel}}: Serializable {{/serializableModel}}{{/parcelizeModels}}{{#parcelizeModels}}{{#serializableModel}} : Parcelable, Serializable {{/serializableModel}}{{/parcelizeModels}}
+){{^isKtor}}{{^serializableModel}}{{#parcelizeModels}} : Parcelable{{/parcelizeModels}}{{/serializableModel}}{{^parcelizeModels}}{{#serializableModel}}: Serializable {{/serializableModel}}{{/parcelizeModels}}{{#parcelizeModels}}{{#serializableModel}} : Parcelable, Serializable {{/serializableModel}}{{/parcelizeModels}}{{/isKtor}}
 {{#vendorExtensions.x-has-data-class-body}}
 {
 {{/vendorExtensions.x-has-data-class-body}}
-{{#serializableModel}}
-    companion object {
-        private const val serialVersionUID: Long = 123
-    }
-{{/serializableModel}}
 {{#hasEnums}}
     {{#vars}}
     {{#isEnum}}

modules/openapi-generator/src/main/resources/kotlin-server/libraries/ktor/ApiKeyAuth.kt.mustache

@@ -1,4 +1,4 @@
-package org.openapitools.server.infrastructure
+package {{packageName}}.infrastructure
 
 import io.ktor.http.auth.*
 import io.ktor.server.application.*

modules/openapi-generator/src/main/resources/kotlin-server/libraries/ktor/AppMain.kt.mustache

@@ -1,7 +1,6 @@
 package {{packageName}}
 
 import io.ktor.server.application.*
-import io.ktor.serialization.gson.*
 import io.ktor.http.*
 {{#featureResources}}
 import io.ktor.server.resources.*
@@ -30,24 +29,17 @@ import java.util.concurrent.TimeUnit
 {{/featureMetrics}}
 import io.ktor.server.routing.*
 {{#hasAuthMethods}}
+import io.ktor.serialization.kotlinx.json.json
 import com.typesafe.config.ConfigFactory
 import io.ktor.client.HttpClient
 import io.ktor.client.engine.apache.Apache
 import io.ktor.server.config.HoconApplicationConfig
 import io.ktor.server.auth.*
-import org.openapitools.server.infrastructure.*
+import {{packageName}}.infrastructure.*
 {{/hasAuthMethods}}
 {{#generateApis}}{{#apiInfo}}{{#apis}}import {{apiPackage}}.{{classname}}
 {{/apis}}{{/apiInfo}}{{/generateApis}}
 
-{{#hasAuthMethods}}
-internal val settings = HoconApplicationConfig(ConfigFactory.defaultApplication(HTTP::class.java.classLoader))
-
-object HTTP {
-    val client = HttpClient(Apache)
-}
-{{/hasAuthMethods}}
-
 fun Application.main() {
     install(DefaultHeaders)
     {{#featureMetrics}}
@@ -62,7 +54,7 @@ fun Application.main() {
     {{/featureMetrics}}
 {{#generateApis}}
     install(ContentNegotiation) {
-        register(ContentType.Application.Json, GsonConverter())
+        json()
     }
     {{#featureAutoHead}}
     install(AutoHeadResponse) // see https://ktor.io/docs/autoheadresponse.html
@@ -125,7 +117,7 @@ fun Application.main() {
     {{/authMethods}}
     }
     {{/hasAuthMethods}}
-    install(Routing) {
+    routing {
     {{#apiInfo}}
     {{#apis}}
     {{#operations}}
@@ -134,6 +126,5 @@ fun Application.main() {
     {{/apis}}
     {{/apiInfo}}
     }
-
 {{/generateApis}}
 }

modules/openapi-generator/src/main/resources/kotlin-server/libraries/ktor/Paths.kt.mustache

@@ -18,10 +18,10 @@ object Paths {
      {{#allParams}}* @param {{paramName}} {{description}} {{^required}}(optional{{#defaultValue}}, default to {{{.}}}{{/defaultValue}}){{/required}}
      {{/allParams}}*/
     {{#hasParams}}
-    @Serializable @Resource("{{{path}}}") class {{operationId}}({{#allParams}}val {{paramName}}: {{{dataType}}}{{^required}}? = null{{/required}}{{#required}}{{#isNullable}}?{{/isNullable}}{{/required}}{{^-last}}, {{/-last}}{{/allParams}})
+    @Resource("{{{path}}}") class {{operationId}}({{#vendorExtensions.ktor-params}}val {{paramName}}: {{{dataType}}}{{^required}}? = null{{/required}}{{#required}}{{#isNullable}}?{{/isNullable}}{{/required}}{{^-last}}, {{/-last}}{{/vendorExtensions.ktor-params}})
     {{/hasParams}}
     {{^hasParams}}
-    @Serializable @Resource("{{{path}}}") class {{operationId}}
+    @Resource("{{{path}}}") class {{operationId}}
     {{/hasParams}}
 
     {{/operation}}

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

@@ -1,10 +1,10 @@
 {{#authMethods}}
 {{#isBasicBasic}}
-val principal = call.authentication.principal<UserIdPrincipal>()!!
+val principal = call.authentication.principal<UserIdPrincipal>()
 {{/isBasicBasic}}{{^isBasicBasic}}{{#isApiKey}}
-val principal = call.authentication.principal<ApiPrincipal>()!!
+val principal = call.authentication.principal<ApiPrincipal>()
 {{/isApiKey}}{{^isApiKey}}{{#isOAuth}}
-val principal = call.authentication.principal<OAuthAccessTokenResponse>()!!
+val principal = call.authentication.principal<OAuthAccessTokenResponse>()
 {{/isOAuth}}{{^isOAuth}}
 val principal = null!!
 {{/isOAuth}}{{/isApiKey}}{{/isBasicBasic}}

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

@@ -2,7 +2,7 @@ val exampleContentType = "{{{contentType}}}"
 val exampleContentString = """{{&example}}"""
 
 when (exampleContentType) {
-    "application/json" -> call.respond(gson.fromJson(exampleContentString, empty::class.java))
+    "application/json" -> call.respondText(exampleContentType, ContentType.Application.Json)
     "application/xml" -> call.respondText(exampleContentString, ContentType.Text.Xml)
     else -> call.respondText(exampleContentString)
 }

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

@@ -1,7 +1,6 @@
 {{>licenseInfo}}
 package {{apiPackage}}
 
-import com.google.gson.Gson
 import io.ktor.http.*
 import io.ktor.server.application.*
 import io.ktor.server.auth.*
@@ -23,7 +22,6 @@ import {{packageName}}.infrastructure.ApiPrincipal
 
 {{#operations}}
 fun Route.{{classname}}() {
-    val gson = Gson()
     val empty = mutableMapOf<String, Any?>()
 
 {{#operation}}

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

@@ -7,7 +7,8 @@ version = "{{artifactVersion}}"
 
 plugins {
     kotlin("jvm") version "2.0.20"
-    id("io.ktor.plugin") version "2.3.12"
+    application
+    kotlin("plugin.serialization") version "2.0.20"
 }
 
 application {
@@ -22,6 +23,7 @@ repositories {
 }
 
 dependencies {
+    implementation(platform("io.ktor:ktor-bom:3.0.2"))
     implementation("ch.qos.logback:logback-classic:$logback_version")
 {{#hasAuthMethods}}
     implementation("com.typesafe:config:1.4.1")
@@ -35,7 +37,7 @@ dependencies {
 {{/featureAutoHead}}
     implementation("io.ktor:ktor-server-default-headers")
     implementation("io.ktor:ktor-server-content-negotiation")
-    implementation("io.ktor:ktor-serialization-gson")
+    implementation("io.ktor:ktor-serialization-kotlinx-json")
 {{#featureResources}}
     implementation("io.ktor:ktor-server-resources")
 {{/featureResources}}

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

@@ -1,4 +1,4 @@
 kotlin.code.style=official
-ktor_version=2.3.12
+ktor_version=3.0.2
 kotlin_version=2.0.20
 logback_version=1.4.14