[Kotlin][Tests]: Add test for kotlin-jvm-okhttp (#20338)

* feat(issue-20231): add echo_api client for kotlin okhttp

* build(issue-20231): sync files

.github/workflows/samples-kotlin-echo-api.yaml

@@ -19,6 +19,7 @@ jobs:
           # clients
           - samples/client/echo_api/kotlin-jvm-spring-3-restclient
           - samples/client/echo_api/kotlin-model-prefix-type-mappings
+          - samples/client/echo_api/kotlin-jvm-okhttp
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-java@v4

.gitignore

@@ -220,6 +220,7 @@ samples/client/petstore/kotlin*/src/main/kotlin/test/
 samples/client/petstore/kotlin*/build/
 samples/server/others/kotlin-server/jaxrs-spec/build/
 samples/client/echo_api/kotlin-jvm-spring-3-restclient/build/
+samples/client/echo_api/kotlin-jvm-okhttp/build/
 
 # haskell
 .stack-work

bin/configs/kotlin-jvm-okhttp-echo-api.yaml

@@ -0,0 +1,8 @@
+generatorName: kotlin
+outputDir: samples/client/echo_api/kotlin-jvm-okhttp
+inputSpec: modules/openapi-generator/src/test/resources/3_0/kotlin/echo_api.yaml
+templateDir: modules/openapi-generator/src/main/resources/kotlin-client
+modelNamePrefix: Api
+additionalProperties:
+  library: jvm-okhttp4
+  artifactId: kotlin-jvm-okhttp-echo-api

samples/client/echo_api/kotlin-jvm-okhttp/.openapi-generator-ignore

@@ -0,0 +1,23 @@
+# OpenAPI Generator Ignore
+# Generated by openapi-generator https://github.com/openapitools/openapi-generator
+
+# Use this file to prevent files from being overwritten by the generator.
+# The patterns follow closely to .gitignore or .dockerignore.
+
+# As an example, the C# client generator defines ApiClient.cs.
+# You can make changes and tell OpenAPI Generator to ignore just this file by uncommenting the following line:
+#ApiClient.cs
+
+# You can match any string of characters against a directory, file or extension with a single asterisk (*):
+#foo/*/qux
+# The above matches foo/bar/qux and foo/baz/qux, but not foo/bar/baz/qux
+
+# You can recursively match patterns against a directory, file or extension with a double asterisk (**):
+#foo/**/qux
+# This matches foo/bar/qux, foo/baz/qux, and foo/bar/baz/qux
+
+# You can also negate patterns with an exclamation (!).
+# For example, you can ignore all files in a docs folder with the file extension .md:
+#docs/*.md
+# Then explicitly reverse the ignore rule for a single file:
+#!docs/README.md

samples/client/echo_api/kotlin-jvm-okhttp/.openapi-generator/FILES

@@ -0,0 +1,54 @@
+README.md
+build.gradle
+docs/AuthApi.md
+docs/Bird.md
+docs/BodyApi.md
+docs/Category.md
+docs/DefaultValue.md
+docs/FormApi.md
+docs/HeaderApi.md
+docs/NumberPropertiesOnly.md
+docs/PathApi.md
+docs/Pet.md
+docs/Query.md
+docs/QueryApi.md
+docs/StringEnumRef.md
+docs/Tag.md
+docs/TestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter.md
+gradle/wrapper/gradle-wrapper.jar
+gradle/wrapper/gradle-wrapper.properties
+gradlew
+gradlew.bat
+settings.gradle
+src/main/kotlin/org/openapitools/client/apis/AuthApi.kt
+src/main/kotlin/org/openapitools/client/apis/BodyApi.kt
+src/main/kotlin/org/openapitools/client/apis/FormApi.kt
+src/main/kotlin/org/openapitools/client/apis/HeaderApi.kt
+src/main/kotlin/org/openapitools/client/apis/PathApi.kt
+src/main/kotlin/org/openapitools/client/apis/QueryApi.kt
+src/main/kotlin/org/openapitools/client/infrastructure/ApiAbstractions.kt
+src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
+src/main/kotlin/org/openapitools/client/infrastructure/ApiResponse.kt
+src/main/kotlin/org/openapitools/client/infrastructure/BigDecimalAdapter.kt
+src/main/kotlin/org/openapitools/client/infrastructure/BigIntegerAdapter.kt
+src/main/kotlin/org/openapitools/client/infrastructure/ByteArrayAdapter.kt
+src/main/kotlin/org/openapitools/client/infrastructure/Errors.kt
+src/main/kotlin/org/openapitools/client/infrastructure/LocalDateAdapter.kt
+src/main/kotlin/org/openapitools/client/infrastructure/LocalDateTimeAdapter.kt
+src/main/kotlin/org/openapitools/client/infrastructure/OffsetDateTimeAdapter.kt
+src/main/kotlin/org/openapitools/client/infrastructure/PartConfig.kt
+src/main/kotlin/org/openapitools/client/infrastructure/RequestConfig.kt
+src/main/kotlin/org/openapitools/client/infrastructure/RequestMethod.kt
+src/main/kotlin/org/openapitools/client/infrastructure/ResponseExtensions.kt
+src/main/kotlin/org/openapitools/client/infrastructure/Serializer.kt
+src/main/kotlin/org/openapitools/client/infrastructure/URIAdapter.kt
+src/main/kotlin/org/openapitools/client/infrastructure/UUIDAdapter.kt
+src/main/kotlin/org/openapitools/client/models/ApiBird.kt
+src/main/kotlin/org/openapitools/client/models/ApiCategory.kt
+src/main/kotlin/org/openapitools/client/models/ApiDefaultValue.kt
+src/main/kotlin/org/openapitools/client/models/ApiNumberPropertiesOnly.kt
+src/main/kotlin/org/openapitools/client/models/ApiPet.kt
+src/main/kotlin/org/openapitools/client/models/ApiQuery.kt
+src/main/kotlin/org/openapitools/client/models/ApiStringEnumRef.kt
+src/main/kotlin/org/openapitools/client/models/ApiTag.kt
+src/main/kotlin/org/openapitools/client/models/ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter.kt

samples/client/echo_api/kotlin-jvm-okhttp/.openapi-generator/VERSION

@@ -0,0 +1 @@
+7.11.0-SNAPSHOT

samples/client/echo_api/kotlin-jvm-okhttp/README.md

@@ -0,0 +1,103 @@
+# org.openapitools.client - Kotlin client library for Echo Server API
+
+Echo Server API
+
+## Overview
+This API client was generated by the [OpenAPI Generator](https://openapi-generator.tech) project.  By using the [openapi-spec](https://github.com/OAI/OpenAPI-Specification) from a remote server, you can easily generate an API client.
+
+- API version: 0.1.0
+- Package version: 
+- Generator version: 7.11.0-SNAPSHOT
+- Build package: org.openapitools.codegen.languages.KotlinClientCodegen
+
+## Requires
+
+* Kotlin 1.7.21
+* Gradle 7.5
+
+## Build
+
+First, create the gradle wrapper script:
+
+```
+gradle wrapper
+```
+
+Then, run:
+
+```
+./gradlew check assemble
+```
+
+This runs all tests and packages the library.
+
+## Features/Implementation Notes
+
+* Supports JSON inputs/outputs, File inputs, and Form inputs.
+* Supports collection formats for query parameters: csv, tsv, ssv, pipes.
+* Some Kotlin and Java types are fully qualified to avoid conflicts with types defined in OpenAPI definitions.
+* Implementation of ApiClient is intended to reduce method counts, specifically to benefit Android targets.
+
+<a id="documentation-for-api-endpoints"></a>
+## Documentation for API Endpoints
+
+All URIs are relative to *http://localhost:3000*
+
+| Class | Method | HTTP request | Description |
+| ------------ | ------------- | ------------- | ------------- |
+| *AuthApi* | [**testAuthHttpBasic**](docs/AuthApi.md#testauthhttpbasic) | **POST** /auth/http/basic | To test HTTP basic authentication |
+| *AuthApi* | [**testAuthHttpBearer**](docs/AuthApi.md#testauthhttpbearer) | **POST** /auth/http/bearer | To test HTTP bearer authentication |
+| *BodyApi* | [**testBinaryGif**](docs/BodyApi.md#testbinarygif) | **POST** /binary/gif | Test binary (gif) response body |
+| *BodyApi* | [**testBodyApplicationOctetstreamBinary**](docs/BodyApi.md#testbodyapplicationoctetstreambinary) | **POST** /body/application/octetstream/binary | Test body parameter(s) |
+| *BodyApi* | [**testBodyMultipartFormdataArrayOfBinary**](docs/BodyApi.md#testbodymultipartformdataarrayofbinary) | **POST** /body/application/octetstream/array_of_binary | Test array of binary in multipart mime |
+| *BodyApi* | [**testBodyMultipartFormdataSingleBinary**](docs/BodyApi.md#testbodymultipartformdatasinglebinary) | **POST** /body/application/octetstream/single_binary | Test single binary in multipart mime |
+| *BodyApi* | [**testEchoBodyFreeFormObjectResponseString**](docs/BodyApi.md#testechobodyfreeformobjectresponsestring) | **POST** /echo/body/FreeFormObject/response_string | Test free form object |
+| *BodyApi* | [**testEchoBodyPet**](docs/BodyApi.md#testechobodypet) | **POST** /echo/body/Pet | Test body parameter(s) |
+| *BodyApi* | [**testEchoBodyPetResponseString**](docs/BodyApi.md#testechobodypetresponsestring) | **POST** /echo/body/Pet/response_string | Test empty response body |
+| *BodyApi* | [**testEchoBodyTagResponseString**](docs/BodyApi.md#testechobodytagresponsestring) | **POST** /echo/body/Tag/response_string | Test empty json (request body) |
+| *FormApi* | [**testFormIntegerBooleanString**](docs/FormApi.md#testformintegerbooleanstring) | **POST** /form/integer/boolean/string | Test form parameter(s) |
+| *FormApi* | [**testFormOneof**](docs/FormApi.md#testformoneof) | **POST** /form/oneof | Test form parameter(s) for oneOf schema |
+| *HeaderApi* | [**testHeaderIntegerBooleanStringEnums**](docs/HeaderApi.md#testheaderintegerbooleanstringenums) | **GET** /header/integer/boolean/string/enums | Test header parameter(s) |
+| *PathApi* | [**testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath**](docs/PathApi.md#testspathstringpathstringintegerpathintegerenumnonrefstringpathenumrefstringpath) | **GET** /path/string/{path_string}/integer/{path_integer}/{enum_nonref_string_path}/{enum_ref_string_path} | Test path parameter(s) |
+| *QueryApi* | [**testEnumRefString**](docs/QueryApi.md#testenumrefstring) | **GET** /query/enum_ref_string | Test query parameter(s) |
+| *QueryApi* | [**testQueryDatetimeDateString**](docs/QueryApi.md#testquerydatetimedatestring) | **GET** /query/datetime/date/string | Test query parameter(s) |
+| *QueryApi* | [**testQueryIntegerBooleanString**](docs/QueryApi.md#testqueryintegerbooleanstring) | **GET** /query/integer/boolean/string | Test query parameter(s) |
+| *QueryApi* | [**testQueryStyleDeepObjectExplodeTrueObject**](docs/QueryApi.md#testquerystyledeepobjectexplodetrueobject) | **GET** /query/style_deepObject/explode_true/object | Test query parameter(s) |
+| *QueryApi* | [**testQueryStyleFormExplodeTrueArrayString**](docs/QueryApi.md#testquerystyleformexplodetruearraystring) | **GET** /query/style_form/explode_true/array_string | Test query parameter(s) |
+| *QueryApi* | [**testQueryStyleFormExplodeTrueObject**](docs/QueryApi.md#testquerystyleformexplodetrueobject) | **GET** /query/style_form/explode_true/object | Test query parameter(s) |
+
+
+<a id="documentation-for-models"></a>
+## Documentation for Models
+
+ - [org.openapitools.client.models.ApiBird](docs/ApiBird.md)
+ - [org.openapitools.client.models.ApiCategory](docs/ApiCategory.md)
+ - [org.openapitools.client.models.ApiDefaultValue](docs/ApiDefaultValue.md)
+ - [org.openapitools.client.models.ApiNumberPropertiesOnly](docs/ApiNumberPropertiesOnly.md)
+ - [org.openapitools.client.models.ApiPet](docs/ApiPet.md)
+ - [org.openapitools.client.models.ApiQuery](docs/ApiQuery.md)
+ - [org.openapitools.client.models.ApiStringEnumRef](docs/ApiStringEnumRef.md)
+ - [org.openapitools.client.models.ApiTag](docs/ApiTag.md)
+ - [org.openapitools.client.models.ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter](docs/ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter.md)
+
+
+<a id="documentation-for-authorization"></a>
+## Documentation for Authorization
+
+
+Authentication schemes defined for the API:
+<a id="http_auth"></a>
+### http_auth
+
+- **Type**: HTTP basic authentication
+
+<a id="http_bearer_auth"></a>
+### http_bearer_auth
+
+- **Type**: HTTP Bearer Token authentication
+
+
+
+## Author
+
+team@openapitools.org

samples/client/echo_api/kotlin-jvm-okhttp/build.gradle

@@ -0,0 +1,62 @@
+group 'org.openapitools'
+version '1.0.0'
+
+wrapper {
+    gradleVersion = '8.7'
+    distributionUrl = "https://services.gradle.org/distributions/gradle-$gradleVersion-all.zip"
+}
+
+buildscript {
+    ext.kotlin_version = '1.9.23'
+    ext.spotless_version = "6.25.0"
+
+    repositories {
+        maven { url "https://repo1.maven.org/maven2" }
+    }
+    dependencies {
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
+    }
+}
+
+apply plugin: 'kotlin'
+apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
+
+repositories {
+    maven { url "https://repo1.maven.org/maven2" }
+}
+
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
+test {
+    useJUnitPlatform()
+}
+
+dependencies {
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
+    implementation "org.jetbrains.kotlin:kotlin-reflect:$kotlin_version"
+    implementation "com.squareup.moshi:moshi-kotlin:1.15.1"
+    implementation "com.squareup.moshi:moshi-adapters:1.15.1"
+    implementation "com.squareup.okhttp3:okhttp:4.12.0"
+    testImplementation "io.kotlintest:kotlintest-runner-junit5:3.4.2"
+}

samples/client/echo_api/kotlin-jvm-okhttp/docs/AuthApi.md

@@ -0,0 +1,101 @@
+# AuthApi
+
+All URIs are relative to *http://localhost:3000*
+
+| Method | HTTP request | Description |
+| ------------- | ------------- | ------------- |
+| [**testAuthHttpBasic**](AuthApi.md#testAuthHttpBasic) | **POST** /auth/http/basic | To test HTTP basic authentication |
+| [**testAuthHttpBearer**](AuthApi.md#testAuthHttpBearer) | **POST** /auth/http/bearer | To test HTTP bearer authentication |
+
+
+<a id="testAuthHttpBasic"></a>
+# **testAuthHttpBasic**
+> kotlin.String testAuthHttpBasic()
+
+To test HTTP basic authentication
+
+To test HTTP basic authentication
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = AuthApi()
+try {
+    val result : kotlin.String = apiInstance.testAuthHttpBasic()
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling AuthApi#testAuthHttpBasic")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling AuthApi#testAuthHttpBasic")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+This endpoint does not need any parameter.
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+
+Configure http_auth:
+    ApiClient.username = ""
+    ApiClient.password = ""
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: text/plain
+
+<a id="testAuthHttpBearer"></a>
+# **testAuthHttpBearer**
+> kotlin.String testAuthHttpBearer()
+
+To test HTTP bearer authentication
+
+To test HTTP bearer authentication
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = AuthApi()
+try {
+    val result : kotlin.String = apiInstance.testAuthHttpBearer()
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling AuthApi#testAuthHttpBearer")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling AuthApi#testAuthHttpBearer")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+This endpoint does not need any parameter.
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+
+Configure http_bearer_auth:
+    ApiClient.accessToken = ""
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: text/plain
+

samples/client/echo_api/kotlin-jvm-okhttp/docs/Bird.md

@@ -0,0 +1,11 @@
+
+# ApiBird
+
+## Properties
+| Name | Type | Description | Notes |
+| ------------ | ------------- | ------------- | ------------- |
+| **propertySize** | **kotlin.String** |  |  [optional] |
+| **color** | **kotlin.String** |  |  [optional] |
+
+
+

samples/client/echo_api/kotlin-jvm-okhttp/docs/BodyApi.md

@@ -0,0 +1,381 @@
+# BodyApi
+
+All URIs are relative to *http://localhost:3000*
+
+| Method | HTTP request | Description |
+| ------------- | ------------- | ------------- |
+| [**testBinaryGif**](BodyApi.md#testBinaryGif) | **POST** /binary/gif | Test binary (gif) response body |
+| [**testBodyApplicationOctetstreamBinary**](BodyApi.md#testBodyApplicationOctetstreamBinary) | **POST** /body/application/octetstream/binary | Test body parameter(s) |
+| [**testBodyMultipartFormdataArrayOfBinary**](BodyApi.md#testBodyMultipartFormdataArrayOfBinary) | **POST** /body/application/octetstream/array_of_binary | Test array of binary in multipart mime |
+| [**testBodyMultipartFormdataSingleBinary**](BodyApi.md#testBodyMultipartFormdataSingleBinary) | **POST** /body/application/octetstream/single_binary | Test single binary in multipart mime |
+| [**testEchoBodyFreeFormObjectResponseString**](BodyApi.md#testEchoBodyFreeFormObjectResponseString) | **POST** /echo/body/FreeFormObject/response_string | Test free form object |
+| [**testEchoBodyPet**](BodyApi.md#testEchoBodyPet) | **POST** /echo/body/Pet | Test body parameter(s) |
+| [**testEchoBodyPetResponseString**](BodyApi.md#testEchoBodyPetResponseString) | **POST** /echo/body/Pet/response_string | Test empty response body |
+| [**testEchoBodyTagResponseString**](BodyApi.md#testEchoBodyTagResponseString) | **POST** /echo/body/Tag/response_string | Test empty json (request body) |
+
+
+<a id="testBinaryGif"></a>
+# **testBinaryGif**
+> java.io.File testBinaryGif()
+
+Test binary (gif) response body
+
+Test binary (gif) response body
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = BodyApi()
+try {
+    val result : java.io.File = apiInstance.testBinaryGif()
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling BodyApi#testBinaryGif")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling BodyApi#testBinaryGif")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+This endpoint does not need any parameter.
+
+### Return type
+
+[**java.io.File**](java.io.File.md)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: Not defined
+
+<a id="testBodyApplicationOctetstreamBinary"></a>
+# **testBodyApplicationOctetstreamBinary**
+> kotlin.String testBodyApplicationOctetstreamBinary(body)
+
+Test body parameter(s)
+
+Test body parameter(s)
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = BodyApi()
+val body : java.io.File = BINARY_DATA_HERE // java.io.File | 
+try {
+    val result : kotlin.String = apiInstance.testBodyApplicationOctetstreamBinary(body)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling BodyApi#testBodyApplicationOctetstreamBinary")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling BodyApi#testBodyApplicationOctetstreamBinary")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **body** | **java.io.File**|  | [optional] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: application/octet-stream
+ - **Accept**: text/plain
+
+<a id="testBodyMultipartFormdataArrayOfBinary"></a>
+# **testBodyMultipartFormdataArrayOfBinary**
+> kotlin.String testBodyMultipartFormdataArrayOfBinary(files)
+
+Test array of binary in multipart mime
+
+Test array of binary in multipart mime
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = BodyApi()
+val files : kotlin.collections.List<java.io.File> = /path/to/file.txt // kotlin.collections.List<java.io.File> | 
+try {
+    val result : kotlin.String = apiInstance.testBodyMultipartFormdataArrayOfBinary(files)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling BodyApi#testBodyMultipartFormdataArrayOfBinary")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling BodyApi#testBodyMultipartFormdataArrayOfBinary")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **files** | **kotlin.collections.List&lt;java.io.File&gt;**|  | |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: multipart/form-data
+ - **Accept**: text/plain
+
+<a id="testBodyMultipartFormdataSingleBinary"></a>
+# **testBodyMultipartFormdataSingleBinary**
+> kotlin.String testBodyMultipartFormdataSingleBinary(myFile)
+
+Test single binary in multipart mime
+
+Test single binary in multipart mime
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = BodyApi()
+val myFile : java.io.File = BINARY_DATA_HERE // java.io.File | 
+try {
+    val result : kotlin.String = apiInstance.testBodyMultipartFormdataSingleBinary(myFile)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling BodyApi#testBodyMultipartFormdataSingleBinary")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling BodyApi#testBodyMultipartFormdataSingleBinary")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **myFile** | **java.io.File**|  | [optional] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: multipart/form-data
+ - **Accept**: text/plain
+
+<a id="testEchoBodyFreeFormObjectResponseString"></a>
+# **testEchoBodyFreeFormObjectResponseString**
+> kotlin.String testEchoBodyFreeFormObjectResponseString(body)
+
+Test free form object
+
+Test free form object
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = BodyApi()
+val body : kotlin.Any = Object // kotlin.Any | Free form object
+try {
+    val result : kotlin.String = apiInstance.testEchoBodyFreeFormObjectResponseString(body)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling BodyApi#testEchoBodyFreeFormObjectResponseString")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling BodyApi#testEchoBodyFreeFormObjectResponseString")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **body** | **kotlin.Any**| Free form object | [optional] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: application/json
+ - **Accept**: text/plain
+
+<a id="testEchoBodyPet"></a>
+# **testEchoBodyPet**
+> ApiPet testEchoBodyPet(apiPet)
+
+Test body parameter(s)
+
+Test body parameter(s)
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = BodyApi()
+val apiPet : ApiPet =  // ApiPet | Pet object that needs to be added to the store
+try {
+    val result : ApiPet = apiInstance.testEchoBodyPet(apiPet)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling BodyApi#testEchoBodyPet")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling BodyApi#testEchoBodyPet")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **apiPet** | [**ApiPet**](ApiPet.md)| Pet object that needs to be added to the store | [optional] |
+
+### Return type
+
+[**ApiPet**](ApiPet.md)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: application/json
+ - **Accept**: application/json
+
+<a id="testEchoBodyPetResponseString"></a>
+# **testEchoBodyPetResponseString**
+> kotlin.String testEchoBodyPetResponseString(apiPet)
+
+Test empty response body
+
+Test empty response body
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = BodyApi()
+val apiPet : ApiPet =  // ApiPet | Pet object that needs to be added to the store
+try {
+    val result : kotlin.String = apiInstance.testEchoBodyPetResponseString(apiPet)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling BodyApi#testEchoBodyPetResponseString")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling BodyApi#testEchoBodyPetResponseString")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **apiPet** | [**ApiPet**](ApiPet.md)| Pet object that needs to be added to the store | [optional] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: application/json
+ - **Accept**: text/plain
+
+<a id="testEchoBodyTagResponseString"></a>
+# **testEchoBodyTagResponseString**
+> kotlin.String testEchoBodyTagResponseString(apiTag)
+
+Test empty json (request body)
+
+Test empty json (request body)
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = BodyApi()
+val apiTag : ApiTag =  // ApiTag | Tag object
+try {
+    val result : kotlin.String = apiInstance.testEchoBodyTagResponseString(apiTag)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling BodyApi#testEchoBodyTagResponseString")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling BodyApi#testEchoBodyTagResponseString")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **apiTag** | [**ApiTag**](ApiTag.md)| Tag object | [optional] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: application/json
+ - **Accept**: text/plain
+

samples/client/echo_api/kotlin-jvm-okhttp/docs/Category.md

@@ -0,0 +1,11 @@
+
+# ApiCategory
+
+## Properties
+| Name | Type | Description | Notes |
+| ------------ | ------------- | ------------- | ------------- |
+| **id** | **kotlin.Long** |  |  [optional] |
+| **name** | **kotlin.String** |  |  [optional] |
+
+
+

samples/client/echo_api/kotlin-jvm-okhttp/docs/DefaultValue.md

@@ -0,0 +1,24 @@
+
+# ApiDefaultValue
+
+## Properties
+| Name | Type | Description | Notes |
+| ------------ | ------------- | ------------- | ------------- |
+| **arrayStringEnumRefDefault** | [**kotlin.collections.List<ApiStringEnumRef>**](ApiStringEnumRef.md) |  |  [optional] |
+| **arrayStringEnumDefault** | [**inline**](#kotlin.collections.List<ArrayStringEnumDefault>) |  |  [optional] |
+| **arrayStringDefault** | **kotlin.collections.List<kotlin.String>** |  |  [optional] |
+| **arrayIntegerDefault** | **kotlin.collections.List<kotlin.Int>** |  |  [optional] |
+| **arrayString** | **kotlin.collections.List<kotlin.String>** |  |  [optional] |
+| **arrayStringNullable** | **kotlin.collections.List<kotlin.String>** |  |  [optional] |
+| **arrayStringExtensionNullable** | **kotlin.collections.List<kotlin.String>** |  |  [optional] |
+| **stringNullable** | **kotlin.String** |  |  [optional] |
+
+
+<a id="kotlin.collections.List<ArrayStringEnumDefault>"></a>
+## Enum: array_string_enum_default
+| Name | Value |
+| ---- | ----- |
+| arrayStringEnumDefault | success, failure, unclassified |
+
+
+

samples/client/echo_api/kotlin-jvm-okhttp/docs/FormApi.md

@@ -0,0 +1,116 @@
+# FormApi
+
+All URIs are relative to *http://localhost:3000*
+
+| Method | HTTP request | Description |
+| ------------- | ------------- | ------------- |
+| [**testFormIntegerBooleanString**](FormApi.md#testFormIntegerBooleanString) | **POST** /form/integer/boolean/string | Test form parameter(s) |
+| [**testFormOneof**](FormApi.md#testFormOneof) | **POST** /form/oneof | Test form parameter(s) for oneOf schema |
+
+
+<a id="testFormIntegerBooleanString"></a>
+# **testFormIntegerBooleanString**
+> kotlin.String testFormIntegerBooleanString(integerForm, booleanForm, stringForm)
+
+Test form parameter(s)
+
+Test form parameter(s)
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = FormApi()
+val integerForm : kotlin.Int = 56 // kotlin.Int | 
+val booleanForm : kotlin.Boolean = true // kotlin.Boolean | 
+val stringForm : kotlin.String = stringForm_example // kotlin.String | 
+try {
+    val result : kotlin.String = apiInstance.testFormIntegerBooleanString(integerForm, booleanForm, stringForm)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling FormApi#testFormIntegerBooleanString")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling FormApi#testFormIntegerBooleanString")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| **integerForm** | **kotlin.Int**|  | [optional] |
+| **booleanForm** | **kotlin.Boolean**|  | [optional] |
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **stringForm** | **kotlin.String**|  | [optional] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: application/x-www-form-urlencoded
+ - **Accept**: text/plain
+
+<a id="testFormOneof"></a>
+# **testFormOneof**
+> kotlin.String testFormOneof(form1, form2, form3, form4, id, name)
+
+Test form parameter(s) for oneOf schema
+
+Test form parameter(s) for oneOf schema
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = FormApi()
+val form1 : kotlin.String = form1_example // kotlin.String | 
+val form2 : kotlin.Int = 56 // kotlin.Int | 
+val form3 : kotlin.String = form3_example // kotlin.String | 
+val form4 : kotlin.Boolean = true // kotlin.Boolean | 
+val id : kotlin.Long = 789 // kotlin.Long | 
+val name : kotlin.String = name_example // kotlin.String | 
+try {
+    val result : kotlin.String = apiInstance.testFormOneof(form1, form2, form3, form4, id, name)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling FormApi#testFormOneof")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling FormApi#testFormOneof")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| **form1** | **kotlin.String**|  | [optional] |
+| **form2** | **kotlin.Int**|  | [optional] |
+| **form3** | **kotlin.String**|  | [optional] |
+| **form4** | **kotlin.Boolean**|  | [optional] |
+| **id** | **kotlin.Long**|  | [optional] |
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **name** | **kotlin.String**|  | [optional] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: application/x-www-form-urlencoded
+ - **Accept**: text/plain
+

samples/client/echo_api/kotlin-jvm-okhttp/docs/HeaderApi.md

@@ -0,0 +1,63 @@
+# HeaderApi
+
+All URIs are relative to *http://localhost:3000*
+
+| Method | HTTP request | Description |
+| ------------- | ------------- | ------------- |
+| [**testHeaderIntegerBooleanStringEnums**](HeaderApi.md#testHeaderIntegerBooleanStringEnums) | **GET** /header/integer/boolean/string/enums | Test header parameter(s) |
+
+
+<a id="testHeaderIntegerBooleanStringEnums"></a>
+# **testHeaderIntegerBooleanStringEnums**
+> kotlin.String testHeaderIntegerBooleanStringEnums(integerHeader, booleanHeader, stringHeader, enumNonrefStringHeader, enumRefStringHeader)
+
+Test header parameter(s)
+
+Test header parameter(s)
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = HeaderApi()
+val integerHeader : kotlin.Int = 56 // kotlin.Int | 
+val booleanHeader : kotlin.Boolean = true // kotlin.Boolean | 
+val stringHeader : kotlin.String = stringHeader_example // kotlin.String | 
+val enumNonrefStringHeader : kotlin.String = enumNonrefStringHeader_example // kotlin.String | 
+val enumRefStringHeader : ApiStringEnumRef =  // ApiStringEnumRef | 
+try {
+    val result : kotlin.String = apiInstance.testHeaderIntegerBooleanStringEnums(integerHeader, booleanHeader, stringHeader, enumNonrefStringHeader, enumRefStringHeader)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling HeaderApi#testHeaderIntegerBooleanStringEnums")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling HeaderApi#testHeaderIntegerBooleanStringEnums")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| **integerHeader** | **kotlin.Int**|  | [optional] |
+| **booleanHeader** | **kotlin.Boolean**|  | [optional] |
+| **stringHeader** | **kotlin.String**|  | [optional] |
+| **enumNonrefStringHeader** | **kotlin.String**|  | [optional] [enum: success, failure, unclassified] |
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **enumRefStringHeader** | [**ApiStringEnumRef**](.md)|  | [optional] [enum: success, failure, unclassified] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: text/plain
+

samples/client/echo_api/kotlin-jvm-okhttp/docs/NumberPropertiesOnly.md

@@ -0,0 +1,12 @@
+
+# ApiNumberPropertiesOnly
+
+## Properties
+| Name | Type | Description | Notes |
+| ------------ | ------------- | ------------- | ------------- |
+| **number** | [**java.math.BigDecimal**](java.math.BigDecimal.md) |  |  [optional] |
+| **float** | **kotlin.Float** |  |  [optional] |
+| **double** | **kotlin.Double** |  |  [optional] |
+
+
+

samples/client/echo_api/kotlin-jvm-okhttp/docs/PathApi.md

@@ -0,0 +1,61 @@
+# PathApi
+
+All URIs are relative to *http://localhost:3000*
+
+| Method | HTTP request | Description |
+| ------------- | ------------- | ------------- |
+| [**testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath**](PathApi.md#testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath) | **GET** /path/string/{path_string}/integer/{path_integer}/{enum_nonref_string_path}/{enum_ref_string_path} | Test path parameter(s) |
+
+
+<a id="testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath"></a>
+# **testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath**
+> kotlin.String testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath(pathString, pathInteger, enumNonrefStringPath, enumRefStringPath)
+
+Test path parameter(s)
+
+Test path parameter(s)
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = PathApi()
+val pathString : kotlin.String = pathString_example // kotlin.String | 
+val pathInteger : kotlin.Int = 56 // kotlin.Int | 
+val enumNonrefStringPath : kotlin.String = enumNonrefStringPath_example // kotlin.String | 
+val enumRefStringPath : ApiStringEnumRef =  // ApiStringEnumRef | 
+try {
+    val result : kotlin.String = apiInstance.testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath(pathString, pathInteger, enumNonrefStringPath, enumRefStringPath)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling PathApi#testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling PathApi#testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| **pathString** | **kotlin.String**|  | |
+| **pathInteger** | **kotlin.Int**|  | |
+| **enumNonrefStringPath** | **kotlin.String**|  | [enum: success, failure, unclassified] |
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **enumRefStringPath** | [**ApiStringEnumRef**](.md)|  | [enum: success, failure, unclassified] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: text/plain
+

samples/client/echo_api/kotlin-jvm-okhttp/docs/Pet.md

@@ -0,0 +1,22 @@
+
+# ApiPet
+
+## Properties
+| Name | Type | Description | Notes |
+| ------------ | ------------- | ------------- | ------------- |
+| **name** | **kotlin.String** |  |  |
+| **photoUrls** | **kotlin.collections.List<kotlin.String>** |  |  |
+| **id** | **kotlin.Long** |  |  [optional] |
+| **category** | [**ApiCategory**](ApiCategory.md) |  |  [optional] |
+| **tags** | [**kotlin.collections.List<ApiTag>**](ApiTag.md) |  |  [optional] |
+| **status** | [**inline**](#Status) | pet status in the store |  [optional] |
+
+
+<a id="Status"></a>
+## Enum: status
+| Name | Value |
+| ---- | ----- |
+| status | available, pending, sold |
+
+
+

samples/client/echo_api/kotlin-jvm-okhttp/docs/Query.md

@@ -0,0 +1,18 @@
+
+# ApiQuery
+
+## Properties
+| Name | Type | Description | Notes |
+| ------------ | ------------- | ------------- | ------------- |
+| **id** | **kotlin.Long** | Query |  [optional] |
+| **outcomes** | [**inline**](#kotlin.collections.List<Outcomes>) |  |  [optional] |
+
+
+<a id="kotlin.collections.List<Outcomes>"></a>
+## Enum: outcomes
+| Name | Value |
+| ---- | ----- |
+| outcomes | SUCCESS, FAILURE, SKIPPED |
+
+
+

samples/client/echo_api/kotlin-jvm-okhttp/docs/QueryApi.md

@@ -0,0 +1,300 @@
+# QueryApi
+
+All URIs are relative to *http://localhost:3000*
+
+| Method | HTTP request | Description |
+| ------------- | ------------- | ------------- |
+| [**testEnumRefString**](QueryApi.md#testEnumRefString) | **GET** /query/enum_ref_string | Test query parameter(s) |
+| [**testQueryDatetimeDateString**](QueryApi.md#testQueryDatetimeDateString) | **GET** /query/datetime/date/string | Test query parameter(s) |
+| [**testQueryIntegerBooleanString**](QueryApi.md#testQueryIntegerBooleanString) | **GET** /query/integer/boolean/string | Test query parameter(s) |
+| [**testQueryStyleDeepObjectExplodeTrueObject**](QueryApi.md#testQueryStyleDeepObjectExplodeTrueObject) | **GET** /query/style_deepObject/explode_true/object | Test query parameter(s) |
+| [**testQueryStyleFormExplodeTrueArrayString**](QueryApi.md#testQueryStyleFormExplodeTrueArrayString) | **GET** /query/style_form/explode_true/array_string | Test query parameter(s) |
+| [**testQueryStyleFormExplodeTrueObject**](QueryApi.md#testQueryStyleFormExplodeTrueObject) | **GET** /query/style_form/explode_true/object | Test query parameter(s) |
+
+
+<a id="testEnumRefString"></a>
+# **testEnumRefString**
+> kotlin.String testEnumRefString(enumNonrefStringQuery, enumRefStringQuery)
+
+Test query parameter(s)
+
+Test query parameter(s)
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = QueryApi()
+val enumNonrefStringQuery : kotlin.String = enumNonrefStringQuery_example // kotlin.String | 
+val enumRefStringQuery : ApiStringEnumRef =  // ApiStringEnumRef | 
+try {
+    val result : kotlin.String = apiInstance.testEnumRefString(enumNonrefStringQuery, enumRefStringQuery)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling QueryApi#testEnumRefString")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling QueryApi#testEnumRefString")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| **enumNonrefStringQuery** | **kotlin.String**|  | [optional] [enum: success, failure, unclassified] |
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **enumRefStringQuery** | [**ApiStringEnumRef**](.md)|  | [optional] [enum: success, failure, unclassified] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: text/plain
+
+<a id="testQueryDatetimeDateString"></a>
+# **testQueryDatetimeDateString**
+> kotlin.String testQueryDatetimeDateString(datetimeQuery, dateQuery, stringQuery)
+
+Test query parameter(s)
+
+Test query parameter(s)
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = QueryApi()
+val datetimeQuery : java.time.OffsetDateTime = 2013-10-20T19:20:30+01:00 // java.time.OffsetDateTime | 
+val dateQuery : java.time.LocalDate = 2013-10-20 // java.time.LocalDate | 
+val stringQuery : kotlin.String = stringQuery_example // kotlin.String | 
+try {
+    val result : kotlin.String = apiInstance.testQueryDatetimeDateString(datetimeQuery, dateQuery, stringQuery)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling QueryApi#testQueryDatetimeDateString")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling QueryApi#testQueryDatetimeDateString")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| **datetimeQuery** | **java.time.OffsetDateTime**|  | [optional] |
+| **dateQuery** | **java.time.LocalDate**|  | [optional] |
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **stringQuery** | **kotlin.String**|  | [optional] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: text/plain
+
+<a id="testQueryIntegerBooleanString"></a>
+# **testQueryIntegerBooleanString**
+> kotlin.String testQueryIntegerBooleanString(integerQuery, booleanQuery, stringQuery)
+
+Test query parameter(s)
+
+Test query parameter(s)
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = QueryApi()
+val integerQuery : kotlin.Int = 56 // kotlin.Int | 
+val booleanQuery : kotlin.Boolean = true // kotlin.Boolean | 
+val stringQuery : kotlin.String = stringQuery_example // kotlin.String | 
+try {
+    val result : kotlin.String = apiInstance.testQueryIntegerBooleanString(integerQuery, booleanQuery, stringQuery)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling QueryApi#testQueryIntegerBooleanString")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling QueryApi#testQueryIntegerBooleanString")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| **integerQuery** | **kotlin.Int**|  | [optional] |
+| **booleanQuery** | **kotlin.Boolean**|  | [optional] |
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **stringQuery** | **kotlin.String**|  | [optional] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: text/plain
+
+<a id="testQueryStyleDeepObjectExplodeTrueObject"></a>
+# **testQueryStyleDeepObjectExplodeTrueObject**
+> kotlin.String testQueryStyleDeepObjectExplodeTrueObject(queryObject)
+
+Test query parameter(s)
+
+Test query parameter(s)
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = QueryApi()
+val queryObject : ApiPet =  // ApiPet | 
+try {
+    val result : kotlin.String = apiInstance.testQueryStyleDeepObjectExplodeTrueObject(queryObject)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling QueryApi#testQueryStyleDeepObjectExplodeTrueObject")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling QueryApi#testQueryStyleDeepObjectExplodeTrueObject")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **queryObject** | [**ApiPet**](.md)|  | [optional] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: text/plain
+
+<a id="testQueryStyleFormExplodeTrueArrayString"></a>
+# **testQueryStyleFormExplodeTrueArrayString**
+> kotlin.String testQueryStyleFormExplodeTrueArrayString(queryObject)
+
+Test query parameter(s)
+
+Test query parameter(s)
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = QueryApi()
+val queryObject : ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter =  // ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter | 
+try {
+    val result : kotlin.String = apiInstance.testQueryStyleFormExplodeTrueArrayString(queryObject)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling QueryApi#testQueryStyleFormExplodeTrueArrayString")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling QueryApi#testQueryStyleFormExplodeTrueArrayString")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **queryObject** | [**ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter**](.md)|  | [optional] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: text/plain
+
+<a id="testQueryStyleFormExplodeTrueObject"></a>
+# **testQueryStyleFormExplodeTrueObject**
+> kotlin.String testQueryStyleFormExplodeTrueObject(queryObject)
+
+Test query parameter(s)
+
+Test query parameter(s)
+
+### Example
+```kotlin
+// Import classes:
+//import org.openapitools.client.infrastructure.*
+//import org.openapitools.client.models.*
+
+val apiInstance = QueryApi()
+val queryObject : ApiPet =  // ApiPet | 
+try {
+    val result : kotlin.String = apiInstance.testQueryStyleFormExplodeTrueObject(queryObject)
+    println(result)
+} catch (e: ClientException) {
+    println("4xx response calling QueryApi#testQueryStyleFormExplodeTrueObject")
+    e.printStackTrace()
+} catch (e: ServerException) {
+    println("5xx response calling QueryApi#testQueryStyleFormExplodeTrueObject")
+    e.printStackTrace()
+}
+```
+
+### Parameters
+| Name | Type | Description  | Notes |
+| ------------- | ------------- | ------------- | ------------- |
+| **queryObject** | [**ApiPet**](.md)|  | [optional] |
+
+### Return type
+
+**kotlin.String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: text/plain
+

samples/client/echo_api/kotlin-jvm-okhttp/docs/StringEnumRef.md

@@ -0,0 +1,14 @@
+
+# ApiStringEnumRef
+
+## Enum
+
+
+    * `success` (value: `"success"`)
+
+    * `failure` (value: `"failure"`)
+
+    * `unclassified` (value: `"unclassified"`)
+
+
+

samples/client/echo_api/kotlin-jvm-okhttp/docs/Tag.md

@@ -0,0 +1,11 @@
+
+# ApiTag
+
+## Properties
+| Name | Type | Description | Notes |
+| ------------ | ------------- | ------------- | ------------- |
+| **id** | **kotlin.Long** |  |  [optional] |
+| **name** | **kotlin.String** |  |  [optional] |
+
+
+

samples/client/echo_api/kotlin-jvm-okhttp/docs/TestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter.md

@@ -0,0 +1,10 @@
+
+# ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter
+
+## Properties
+| Name | Type | Description | Notes |
+| ------------ | ------------- | ------------- | ------------- |
+| **propertyValues** | **kotlin.collections.List<kotlin.String>** |  |  [optional] |
+
+
+

samples/client/echo_api/kotlin-jvm-okhttp/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,7 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.7-all.zip
+networkTimeout=10000
+validateDistributionUrl=true
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

samples/client/echo_api/kotlin-jvm-okhttp/gradlew

@@ -0,0 +1,249 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/HEAD/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+[ -h "$app_path" ]
+do
+ls=$( ls -ld "$app_path" )
+link=${ls#*' -> '}
+case $link in             #(
+/*)   app_path=$link ;; #(
+*)    app_path=$APP_HOME$link ;;
+esac
+done
+
+# This is normally unused
+# shellcheck disable=SC2034
+APP_BASE_NAME=${0##*/}
+# Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
+APP_HOME=$( cd "${APP_HOME:-./}" > /dev/null && pwd -P ) || exit
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+echo "$*"
+} >&2
+
+die () {
+echo
+echo "$*"
+echo
+exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+CYGWIN* )         cygwin=true  ;; #(
+Darwin* )         darwin=true  ;; #(
+MSYS* | MINGW* )  msys=true    ;; #(
+NONSTOP* )        nonstop=true ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+# IBM's JDK on AIX uses strange locations for the executables
+JAVACMD=$JAVA_HOME/jre/sh/java
+else
+JAVACMD=$JAVA_HOME/bin/java
+fi
+if [ ! -x "$JAVACMD" ] ; then
+die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+else
+JAVACMD=java
+if ! command -v java >/dev/null 2>&1
+then
+die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+case $MAX_FD in #(
+max*)
+# In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+# shellcheck disable=SC2039,SC3045
+MAX_FD=$( ulimit -H -n ) ||
+warn "Could not query maximum file descriptor limit"
+esac
+case $MAX_FD in  #(
+'' | soft) :;; #(
+*)
+# In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+# shellcheck disable=SC2039,SC3045
+ulimit -n "$MAX_FD" ||
+warn "Could not set maximum file descriptor limit to $MAX_FD"
+esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+# Now convert the arguments - kludge to limit ourselves to /bin/sh
+for arg do
+if
+case $arg in                                #(
+-*)   false ;;                            # don't mess with options #(
+/?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+[ -e "$t" ] ;;                      #(
+*)    false ;;
+esac
+then
+arg=$( cygpath --path --ignore --mixed "$arg" )
+fi
+# Roll the args list around exactly as many times as the number of
+# args, so each arg winds up back in the position where it started, but
+# possibly modified.
+#
+# NB: a `for` loop captures its iteration list before it begins, so
+# changing the positional parameters here affects neither the number of
+# iterations, nor the values presented in `arg`.
+shift                   # remove old arg
+set -- "$@" "$arg"      # push replacement arg
+done
+fi
+
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Collect all arguments for the java command:
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
+#     and any embedded shellness will be escaped.
+#   * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be
+#     treated as '${Hostname}' itself on the command line.
+
+set -- \
+"-Dorg.gradle.appname=$APP_BASE_NAME" \
+-classpath "$CLASSPATH" \
+org.gradle.wrapper.GradleWrapperMain \
+"$@"
+
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+die "xargs is not available"
+fi
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+xargs -n1 |
+sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+tr '\n' ' '
+)" '"$@"'
+
+exec "$JAVACMD" "$@"

samples/client/echo_api/kotlin-jvm-okhttp/gradlew.bat

@@ -0,0 +1,89 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

samples/client/echo_api/kotlin-jvm-okhttp/settings.gradle

@@ -0,0 +1 @@
+rootProject.name = 'kotlin-jvm-okhttp-echo-api'

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/apis/AuthApi.kt

@@ -0,0 +1,186 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.apis
+
+import java.io.IOException
+import okhttp3.Call
+import okhttp3.HttpUrl
+
+
+import com.squareup.moshi.Json
+
+import org.openapitools.client.infrastructure.ApiClient
+import org.openapitools.client.infrastructure.ApiResponse
+import org.openapitools.client.infrastructure.ClientException
+import org.openapitools.client.infrastructure.ClientError
+import org.openapitools.client.infrastructure.ServerException
+import org.openapitools.client.infrastructure.ServerError
+import org.openapitools.client.infrastructure.MultiValueMap
+import org.openapitools.client.infrastructure.PartConfig
+import org.openapitools.client.infrastructure.RequestConfig
+import org.openapitools.client.infrastructure.RequestMethod
+import org.openapitools.client.infrastructure.ResponseType
+import org.openapitools.client.infrastructure.Success
+import org.openapitools.client.infrastructure.toMultiValue
+
+class AuthApi(basePath: kotlin.String = defaultBasePath, client: Call.Factory = ApiClient.defaultClient) : ApiClient(basePath, client) {
+    companion object {
+        @JvmStatic
+        val defaultBasePath: String by lazy {
+            System.getProperties().getProperty(ApiClient.baseUrlKey, "http://localhost:3000")
+        }
+    }
+
+    /**
+     * To test HTTP basic authentication
+     * To test HTTP basic authentication
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testAuthHttpBasic() : kotlin.String {
+        val localVarResponse = testAuthHttpBasicWithHttpInfo()
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * To test HTTP basic authentication
+     * To test HTTP basic authentication
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testAuthHttpBasicWithHttpInfo() : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testAuthHttpBasicRequestConfig()
+
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testAuthHttpBasic
+     *
+     * @return RequestConfig
+     */
+    fun testAuthHttpBasicRequestConfig() : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery: MultiValueMap = mutableMapOf()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/auth/http/basic",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = true,
+            body = localVariableBody
+        )
+    }
+
+    /**
+     * To test HTTP bearer authentication
+     * To test HTTP bearer authentication
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testAuthHttpBearer() : kotlin.String {
+        val localVarResponse = testAuthHttpBearerWithHttpInfo()
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * To test HTTP bearer authentication
+     * To test HTTP bearer authentication
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testAuthHttpBearerWithHttpInfo() : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testAuthHttpBearerRequestConfig()
+
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testAuthHttpBearer
+     *
+     * @return RequestConfig
+     */
+    fun testAuthHttpBearerRequestConfig() : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery: MultiValueMap = mutableMapOf()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/auth/http/bearer",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = true,
+            body = localVariableBody
+        )
+    }
+
+
+    private fun encodeURIComponent(uriComponent: kotlin.String): kotlin.String =
+        HttpUrl.Builder().scheme("http").host("localhost").addPathSegment(uriComponent).build().encodedPathSegments[0]
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/apis/BodyApi.kt

@@ -0,0 +1,623 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.apis
+
+import java.io.IOException
+import okhttp3.Call
+import okhttp3.HttpUrl
+
+import org.openapitools.client.models.ApiPet
+import org.openapitools.client.models.ApiTag
+
+import com.squareup.moshi.Json
+
+import org.openapitools.client.infrastructure.ApiClient
+import org.openapitools.client.infrastructure.ApiResponse
+import org.openapitools.client.infrastructure.ClientException
+import org.openapitools.client.infrastructure.ClientError
+import org.openapitools.client.infrastructure.ServerException
+import org.openapitools.client.infrastructure.ServerError
+import org.openapitools.client.infrastructure.MultiValueMap
+import org.openapitools.client.infrastructure.PartConfig
+import org.openapitools.client.infrastructure.RequestConfig
+import org.openapitools.client.infrastructure.RequestMethod
+import org.openapitools.client.infrastructure.ResponseType
+import org.openapitools.client.infrastructure.Success
+import org.openapitools.client.infrastructure.toMultiValue
+
+class BodyApi(basePath: kotlin.String = defaultBasePath, client: Call.Factory = ApiClient.defaultClient) : ApiClient(basePath, client) {
+    companion object {
+        @JvmStatic
+        val defaultBasePath: String by lazy {
+            System.getProperties().getProperty(ApiClient.baseUrlKey, "http://localhost:3000")
+        }
+    }
+
+    /**
+     * Test binary (gif) response body
+     * Test binary (gif) response body
+     * @return java.io.File
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testBinaryGif() : java.io.File {
+        val localVarResponse = testBinaryGifWithHttpInfo()
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as java.io.File
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test binary (gif) response body
+     * Test binary (gif) response body
+     * @return ApiResponse<java.io.File?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testBinaryGifWithHttpInfo() : ApiResponse<java.io.File?> {
+        val localVariableConfig = testBinaryGifRequestConfig()
+
+        return request<Unit, java.io.File>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testBinaryGif
+     *
+     * @return RequestConfig
+     */
+    fun testBinaryGifRequestConfig() : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery: MultiValueMap = mutableMapOf()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/binary/gif",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+    /**
+     * Test body parameter(s)
+     * Test body parameter(s)
+     * @param body  (optional)
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testBodyApplicationOctetstreamBinary(body: java.io.File? = null) : kotlin.String {
+        val localVarResponse = testBodyApplicationOctetstreamBinaryWithHttpInfo(body = body)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test body parameter(s)
+     * Test body parameter(s)
+     * @param body  (optional)
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testBodyApplicationOctetstreamBinaryWithHttpInfo(body: java.io.File?) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testBodyApplicationOctetstreamBinaryRequestConfig(body = body)
+
+        return request<java.io.File, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testBodyApplicationOctetstreamBinary
+     *
+     * @param body  (optional)
+     * @return RequestConfig
+     */
+    fun testBodyApplicationOctetstreamBinaryRequestConfig(body: java.io.File?) : RequestConfig<java.io.File> {
+        val localVariableBody = body
+        val localVariableQuery: MultiValueMap = mutableMapOf()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Content-Type"] = "application/octet-stream"
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/body/application/octetstream/binary",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+    /**
+     * Test array of binary in multipart mime
+     * Test array of binary in multipart mime
+     * @param files 
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testBodyMultipartFormdataArrayOfBinary(files: kotlin.collections.List<java.io.File>) : kotlin.String {
+        val localVarResponse = testBodyMultipartFormdataArrayOfBinaryWithHttpInfo(files = files)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test array of binary in multipart mime
+     * Test array of binary in multipart mime
+     * @param files 
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testBodyMultipartFormdataArrayOfBinaryWithHttpInfo(files: kotlin.collections.List<java.io.File>) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testBodyMultipartFormdataArrayOfBinaryRequestConfig(files = files)
+
+        return request<Map<String, PartConfig<*>>, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testBodyMultipartFormdataArrayOfBinary
+     *
+     * @param files 
+     * @return RequestConfig
+     */
+    fun testBodyMultipartFormdataArrayOfBinaryRequestConfig(files: kotlin.collections.List<java.io.File>) : RequestConfig<Map<String, PartConfig<*>>> {
+        val localVariableBody = mapOf(
+            "files" to PartConfig(body = files, headers = mutableMapOf()),)
+        val localVariableQuery: MultiValueMap = mutableMapOf()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf("Content-Type" to "multipart/form-data")
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/body/application/octetstream/array_of_binary",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+    /**
+     * Test single binary in multipart mime
+     * Test single binary in multipart mime
+     * @param myFile  (optional)
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testBodyMultipartFormdataSingleBinary(myFile: java.io.File? = null) : kotlin.String {
+        val localVarResponse = testBodyMultipartFormdataSingleBinaryWithHttpInfo(myFile = myFile)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test single binary in multipart mime
+     * Test single binary in multipart mime
+     * @param myFile  (optional)
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testBodyMultipartFormdataSingleBinaryWithHttpInfo(myFile: java.io.File?) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testBodyMultipartFormdataSingleBinaryRequestConfig(myFile = myFile)
+
+        return request<Map<String, PartConfig<*>>, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testBodyMultipartFormdataSingleBinary
+     *
+     * @param myFile  (optional)
+     * @return RequestConfig
+     */
+    fun testBodyMultipartFormdataSingleBinaryRequestConfig(myFile: java.io.File?) : RequestConfig<Map<String, PartConfig<*>>> {
+        val localVariableBody = mapOf(
+            "my-file" to PartConfig(body = myFile, headers = mutableMapOf()),)
+        val localVariableQuery: MultiValueMap = mutableMapOf()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf("Content-Type" to "multipart/form-data")
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/body/application/octetstream/single_binary",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+    /**
+     * Test free form object
+     * Test free form object
+     * @param body Free form object (optional)
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testEchoBodyFreeFormObjectResponseString(body: kotlin.Any? = null) : kotlin.String {
+        val localVarResponse = testEchoBodyFreeFormObjectResponseStringWithHttpInfo(body = body)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test free form object
+     * Test free form object
+     * @param body Free form object (optional)
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testEchoBodyFreeFormObjectResponseStringWithHttpInfo(body: kotlin.Any?) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testEchoBodyFreeFormObjectResponseStringRequestConfig(body = body)
+
+        return request<kotlin.Any, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testEchoBodyFreeFormObjectResponseString
+     *
+     * @param body Free form object (optional)
+     * @return RequestConfig
+     */
+    fun testEchoBodyFreeFormObjectResponseStringRequestConfig(body: kotlin.Any?) : RequestConfig<kotlin.Any> {
+        val localVariableBody = body
+        val localVariableQuery: MultiValueMap = mutableMapOf()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Content-Type"] = "application/json"
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/echo/body/FreeFormObject/response_string",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+    /**
+     * Test body parameter(s)
+     * Test body parameter(s)
+     * @param apiPet Pet object that needs to be added to the store (optional)
+     * @return ApiPet
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testEchoBodyPet(apiPet: ApiPet? = null) : ApiPet {
+        val localVarResponse = testEchoBodyPetWithHttpInfo(apiPet = apiPet)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as ApiPet
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test body parameter(s)
+     * Test body parameter(s)
+     * @param apiPet Pet object that needs to be added to the store (optional)
+     * @return ApiResponse<ApiPet?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testEchoBodyPetWithHttpInfo(apiPet: ApiPet?) : ApiResponse<ApiPet?> {
+        val localVariableConfig = testEchoBodyPetRequestConfig(apiPet = apiPet)
+
+        return request<ApiPet, ApiPet>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testEchoBodyPet
+     *
+     * @param apiPet Pet object that needs to be added to the store (optional)
+     * @return RequestConfig
+     */
+    fun testEchoBodyPetRequestConfig(apiPet: ApiPet?) : RequestConfig<ApiPet> {
+        val localVariableBody = apiPet
+        val localVariableQuery: MultiValueMap = mutableMapOf()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Content-Type"] = "application/json"
+        localVariableHeaders["Accept"] = "application/json"
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/echo/body/Pet",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+    /**
+     * Test empty response body
+     * Test empty response body
+     * @param apiPet Pet object that needs to be added to the store (optional)
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testEchoBodyPetResponseString(apiPet: ApiPet? = null) : kotlin.String {
+        val localVarResponse = testEchoBodyPetResponseStringWithHttpInfo(apiPet = apiPet)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test empty response body
+     * Test empty response body
+     * @param apiPet Pet object that needs to be added to the store (optional)
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testEchoBodyPetResponseStringWithHttpInfo(apiPet: ApiPet?) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testEchoBodyPetResponseStringRequestConfig(apiPet = apiPet)
+
+        return request<ApiPet, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testEchoBodyPetResponseString
+     *
+     * @param apiPet Pet object that needs to be added to the store (optional)
+     * @return RequestConfig
+     */
+    fun testEchoBodyPetResponseStringRequestConfig(apiPet: ApiPet?) : RequestConfig<ApiPet> {
+        val localVariableBody = apiPet
+        val localVariableQuery: MultiValueMap = mutableMapOf()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Content-Type"] = "application/json"
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/echo/body/Pet/response_string",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+    /**
+     * Test empty json (request body)
+     * Test empty json (request body)
+     * @param apiTag Tag object (optional)
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testEchoBodyTagResponseString(apiTag: ApiTag? = null) : kotlin.String {
+        val localVarResponse = testEchoBodyTagResponseStringWithHttpInfo(apiTag = apiTag)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test empty json (request body)
+     * Test empty json (request body)
+     * @param apiTag Tag object (optional)
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testEchoBodyTagResponseStringWithHttpInfo(apiTag: ApiTag?) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testEchoBodyTagResponseStringRequestConfig(apiTag = apiTag)
+
+        return request<ApiTag, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testEchoBodyTagResponseString
+     *
+     * @param apiTag Tag object (optional)
+     * @return RequestConfig
+     */
+    fun testEchoBodyTagResponseStringRequestConfig(apiTag: ApiTag?) : RequestConfig<ApiTag> {
+        val localVariableBody = apiTag
+        val localVariableQuery: MultiValueMap = mutableMapOf()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Content-Type"] = "application/json"
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/echo/body/Tag/response_string",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    private fun encodeURIComponent(uriComponent: kotlin.String): kotlin.String =
+        HttpUrl.Builder().scheme("http").host("localhost").addPathSegment(uriComponent).build().encodedPathSegments[0]
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/apis/FormApi.kt

@@ -0,0 +1,222 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.apis
+
+import java.io.IOException
+import okhttp3.Call
+import okhttp3.HttpUrl
+
+
+import com.squareup.moshi.Json
+
+import org.openapitools.client.infrastructure.ApiClient
+import org.openapitools.client.infrastructure.ApiResponse
+import org.openapitools.client.infrastructure.ClientException
+import org.openapitools.client.infrastructure.ClientError
+import org.openapitools.client.infrastructure.ServerException
+import org.openapitools.client.infrastructure.ServerError
+import org.openapitools.client.infrastructure.MultiValueMap
+import org.openapitools.client.infrastructure.PartConfig
+import org.openapitools.client.infrastructure.RequestConfig
+import org.openapitools.client.infrastructure.RequestMethod
+import org.openapitools.client.infrastructure.ResponseType
+import org.openapitools.client.infrastructure.Success
+import org.openapitools.client.infrastructure.toMultiValue
+
+class FormApi(basePath: kotlin.String = defaultBasePath, client: Call.Factory = ApiClient.defaultClient) : ApiClient(basePath, client) {
+    companion object {
+        @JvmStatic
+        val defaultBasePath: String by lazy {
+            System.getProperties().getProperty(ApiClient.baseUrlKey, "http://localhost:3000")
+        }
+    }
+
+    /**
+     * Test form parameter(s)
+     * Test form parameter(s)
+     * @param integerForm  (optional)
+     * @param booleanForm  (optional)
+     * @param stringForm  (optional)
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testFormIntegerBooleanString(integerForm: kotlin.Int? = null, booleanForm: kotlin.Boolean? = null, stringForm: kotlin.String? = null) : kotlin.String {
+        val localVarResponse = testFormIntegerBooleanStringWithHttpInfo(integerForm = integerForm, booleanForm = booleanForm, stringForm = stringForm)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test form parameter(s)
+     * Test form parameter(s)
+     * @param integerForm  (optional)
+     * @param booleanForm  (optional)
+     * @param stringForm  (optional)
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testFormIntegerBooleanStringWithHttpInfo(integerForm: kotlin.Int?, booleanForm: kotlin.Boolean?, stringForm: kotlin.String?) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testFormIntegerBooleanStringRequestConfig(integerForm = integerForm, booleanForm = booleanForm, stringForm = stringForm)
+
+        return request<Map<String, PartConfig<*>>, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testFormIntegerBooleanString
+     *
+     * @param integerForm  (optional)
+     * @param booleanForm  (optional)
+     * @param stringForm  (optional)
+     * @return RequestConfig
+     */
+    fun testFormIntegerBooleanStringRequestConfig(integerForm: kotlin.Int?, booleanForm: kotlin.Boolean?, stringForm: kotlin.String?) : RequestConfig<Map<String, PartConfig<*>>> {
+        val localVariableBody = mapOf(
+            "integer_form" to PartConfig(body = integerForm, headers = mutableMapOf()),
+            "boolean_form" to PartConfig(body = booleanForm, headers = mutableMapOf()),
+            "string_form" to PartConfig(body = stringForm, headers = mutableMapOf()),)
+        val localVariableQuery: MultiValueMap = mutableMapOf()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf("Content-Type" to "application/x-www-form-urlencoded")
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/form/integer/boolean/string",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+    /**
+     * Test form parameter(s) for oneOf schema
+     * Test form parameter(s) for oneOf schema
+     * @param form1  (optional)
+     * @param form2  (optional)
+     * @param form3  (optional)
+     * @param form4  (optional)
+     * @param id  (optional)
+     * @param name  (optional)
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testFormOneof(form1: kotlin.String? = null, form2: kotlin.Int? = null, form3: kotlin.String? = null, form4: kotlin.Boolean? = null, id: kotlin.Long? = null, name: kotlin.String? = null) : kotlin.String {
+        val localVarResponse = testFormOneofWithHttpInfo(form1 = form1, form2 = form2, form3 = form3, form4 = form4, id = id, name = name)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test form parameter(s) for oneOf schema
+     * Test form parameter(s) for oneOf schema
+     * @param form1  (optional)
+     * @param form2  (optional)
+     * @param form3  (optional)
+     * @param form4  (optional)
+     * @param id  (optional)
+     * @param name  (optional)
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testFormOneofWithHttpInfo(form1: kotlin.String?, form2: kotlin.Int?, form3: kotlin.String?, form4: kotlin.Boolean?, id: kotlin.Long?, name: kotlin.String?) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testFormOneofRequestConfig(form1 = form1, form2 = form2, form3 = form3, form4 = form4, id = id, name = name)
+
+        return request<Map<String, PartConfig<*>>, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testFormOneof
+     *
+     * @param form1  (optional)
+     * @param form2  (optional)
+     * @param form3  (optional)
+     * @param form4  (optional)
+     * @param id  (optional)
+     * @param name  (optional)
+     * @return RequestConfig
+     */
+    fun testFormOneofRequestConfig(form1: kotlin.String?, form2: kotlin.Int?, form3: kotlin.String?, form4: kotlin.Boolean?, id: kotlin.Long?, name: kotlin.String?) : RequestConfig<Map<String, PartConfig<*>>> {
+        val localVariableBody = mapOf(
+            "form1" to PartConfig(body = form1, headers = mutableMapOf()),
+            "form2" to PartConfig(body = form2, headers = mutableMapOf()),
+            "form3" to PartConfig(body = form3, headers = mutableMapOf()),
+            "form4" to PartConfig(body = form4, headers = mutableMapOf()),
+            "id" to PartConfig(body = id, headers = mutableMapOf()),
+            "name" to PartConfig(body = name, headers = mutableMapOf()),)
+        val localVariableQuery: MultiValueMap = mutableMapOf()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf("Content-Type" to "application/x-www-form-urlencoded")
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/form/oneof",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    private fun encodeURIComponent(uriComponent: kotlin.String): kotlin.String =
+        HttpUrl.Builder().scheme("http").host("localhost").addPathSegment(uriComponent).build().encodedPathSegments[0]
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/apis/HeaderApi.kt

@@ -0,0 +1,157 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.apis
+
+import java.io.IOException
+import okhttp3.Call
+import okhttp3.HttpUrl
+
+import org.openapitools.client.models.ApiStringEnumRef
+
+import com.squareup.moshi.Json
+
+import org.openapitools.client.infrastructure.ApiClient
+import org.openapitools.client.infrastructure.ApiResponse
+import org.openapitools.client.infrastructure.ClientException
+import org.openapitools.client.infrastructure.ClientError
+import org.openapitools.client.infrastructure.ServerException
+import org.openapitools.client.infrastructure.ServerError
+import org.openapitools.client.infrastructure.MultiValueMap
+import org.openapitools.client.infrastructure.PartConfig
+import org.openapitools.client.infrastructure.RequestConfig
+import org.openapitools.client.infrastructure.RequestMethod
+import org.openapitools.client.infrastructure.ResponseType
+import org.openapitools.client.infrastructure.Success
+import org.openapitools.client.infrastructure.toMultiValue
+
+class HeaderApi(basePath: kotlin.String = defaultBasePath, client: Call.Factory = ApiClient.defaultClient) : ApiClient(basePath, client) {
+    companion object {
+        @JvmStatic
+        val defaultBasePath: String by lazy {
+            System.getProperties().getProperty(ApiClient.baseUrlKey, "http://localhost:3000")
+        }
+    }
+
+    /**
+     * enum for parameter enumNonrefStringHeader
+     */
+     enum class EnumNonrefStringHeaderTestHeaderIntegerBooleanStringEnums(val value: kotlin.String) {
+         @Json(name = "success") success("success"),
+         @Json(name = "failure") failure("failure"),
+         @Json(name = "unclassified") unclassified("unclassified");
+
+        /**
+         * Override [toString()] to avoid using the enum variable name as the value, and instead use
+         * the actual value defined in the API spec file.
+         *
+         * This solves a problem when the variable name and its value are different, and ensures that
+         * the client sends the correct enum values to the server always.
+         */
+        override fun toString(): kotlin.String = "$value"
+     }
+
+    /**
+     * Test header parameter(s)
+     * Test header parameter(s)
+     * @param integerHeader  (optional)
+     * @param booleanHeader  (optional)
+     * @param stringHeader  (optional)
+     * @param enumNonrefStringHeader  (optional)
+     * @param enumRefStringHeader  (optional)
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testHeaderIntegerBooleanStringEnums(integerHeader: kotlin.Int? = null, booleanHeader: kotlin.Boolean? = null, stringHeader: kotlin.String? = null, enumNonrefStringHeader: EnumNonrefStringHeaderTestHeaderIntegerBooleanStringEnums? = null, enumRefStringHeader: ApiStringEnumRef? = null) : kotlin.String {
+        val localVarResponse = testHeaderIntegerBooleanStringEnumsWithHttpInfo(integerHeader = integerHeader, booleanHeader = booleanHeader, stringHeader = stringHeader, enumNonrefStringHeader = enumNonrefStringHeader, enumRefStringHeader = enumRefStringHeader)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test header parameter(s)
+     * Test header parameter(s)
+     * @param integerHeader  (optional)
+     * @param booleanHeader  (optional)
+     * @param stringHeader  (optional)
+     * @param enumNonrefStringHeader  (optional)
+     * @param enumRefStringHeader  (optional)
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testHeaderIntegerBooleanStringEnumsWithHttpInfo(integerHeader: kotlin.Int?, booleanHeader: kotlin.Boolean?, stringHeader: kotlin.String?, enumNonrefStringHeader: EnumNonrefStringHeaderTestHeaderIntegerBooleanStringEnums?, enumRefStringHeader: ApiStringEnumRef?) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testHeaderIntegerBooleanStringEnumsRequestConfig(integerHeader = integerHeader, booleanHeader = booleanHeader, stringHeader = stringHeader, enumNonrefStringHeader = enumNonrefStringHeader, enumRefStringHeader = enumRefStringHeader)
+
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testHeaderIntegerBooleanStringEnums
+     *
+     * @param integerHeader  (optional)
+     * @param booleanHeader  (optional)
+     * @param stringHeader  (optional)
+     * @param enumNonrefStringHeader  (optional)
+     * @param enumRefStringHeader  (optional)
+     * @return RequestConfig
+     */
+    fun testHeaderIntegerBooleanStringEnumsRequestConfig(integerHeader: kotlin.Int?, booleanHeader: kotlin.Boolean?, stringHeader: kotlin.String?, enumNonrefStringHeader: EnumNonrefStringHeaderTestHeaderIntegerBooleanStringEnums?, enumRefStringHeader: ApiStringEnumRef?) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery: MultiValueMap = mutableMapOf()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        integerHeader?.apply { localVariableHeaders["integer_header"] = this.toString() }
+        booleanHeader?.apply { localVariableHeaders["boolean_header"] = this.toString() }
+        stringHeader?.apply { localVariableHeaders["string_header"] = this.toString() }
+        enumNonrefStringHeader?.apply { localVariableHeaders["enum_nonref_string_header"] = this.toString() }
+        enumRefStringHeader?.apply { localVariableHeaders["enum_ref_string_header"] = this.toString() }
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/header/integer/boolean/string/enums",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    private fun encodeURIComponent(uriComponent: kotlin.String): kotlin.String =
+        HttpUrl.Builder().scheme("http").host("localhost").addPathSegment(uriComponent).build().encodedPathSegments[0]
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/apis/PathApi.kt

@@ -0,0 +1,149 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.apis
+
+import java.io.IOException
+import okhttp3.Call
+import okhttp3.HttpUrl
+
+import org.openapitools.client.models.ApiStringEnumRef
+
+import com.squareup.moshi.Json
+
+import org.openapitools.client.infrastructure.ApiClient
+import org.openapitools.client.infrastructure.ApiResponse
+import org.openapitools.client.infrastructure.ClientException
+import org.openapitools.client.infrastructure.ClientError
+import org.openapitools.client.infrastructure.ServerException
+import org.openapitools.client.infrastructure.ServerError
+import org.openapitools.client.infrastructure.MultiValueMap
+import org.openapitools.client.infrastructure.PartConfig
+import org.openapitools.client.infrastructure.RequestConfig
+import org.openapitools.client.infrastructure.RequestMethod
+import org.openapitools.client.infrastructure.ResponseType
+import org.openapitools.client.infrastructure.Success
+import org.openapitools.client.infrastructure.toMultiValue
+
+class PathApi(basePath: kotlin.String = defaultBasePath, client: Call.Factory = ApiClient.defaultClient) : ApiClient(basePath, client) {
+    companion object {
+        @JvmStatic
+        val defaultBasePath: String by lazy {
+            System.getProperties().getProperty(ApiClient.baseUrlKey, "http://localhost:3000")
+        }
+    }
+
+    /**
+     * enum for parameter enumNonrefStringPath
+     */
+     enum class EnumNonrefStringPathTestsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath(val value: kotlin.String) {
+         @Json(name = "success") success("success"),
+         @Json(name = "failure") failure("failure"),
+         @Json(name = "unclassified") unclassified("unclassified");
+
+        /**
+         * Override [toString()] to avoid using the enum variable name as the value, and instead use
+         * the actual value defined in the API spec file.
+         *
+         * This solves a problem when the variable name and its value are different, and ensures that
+         * the client sends the correct enum values to the server always.
+         */
+        override fun toString(): kotlin.String = "$value"
+     }
+
+    /**
+     * Test path parameter(s)
+     * Test path parameter(s)
+     * @param pathString 
+     * @param pathInteger 
+     * @param enumNonrefStringPath 
+     * @param enumRefStringPath 
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath(pathString: kotlin.String, pathInteger: kotlin.Int, enumNonrefStringPath: EnumNonrefStringPathTestsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath, enumRefStringPath: ApiStringEnumRef) : kotlin.String {
+        val localVarResponse = testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPathWithHttpInfo(pathString = pathString, pathInteger = pathInteger, enumNonrefStringPath = enumNonrefStringPath, enumRefStringPath = enumRefStringPath)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test path parameter(s)
+     * Test path parameter(s)
+     * @param pathString 
+     * @param pathInteger 
+     * @param enumNonrefStringPath 
+     * @param enumRefStringPath 
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPathWithHttpInfo(pathString: kotlin.String, pathInteger: kotlin.Int, enumNonrefStringPath: EnumNonrefStringPathTestsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath, enumRefStringPath: ApiStringEnumRef) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPathRequestConfig(pathString = pathString, pathInteger = pathInteger, enumNonrefStringPath = enumNonrefStringPath, enumRefStringPath = enumRefStringPath)
+
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath
+     *
+     * @param pathString 
+     * @param pathInteger 
+     * @param enumNonrefStringPath 
+     * @param enumRefStringPath 
+     * @return RequestConfig
+     */
+    fun testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPathRequestConfig(pathString: kotlin.String, pathInteger: kotlin.Int, enumNonrefStringPath: EnumNonrefStringPathTestsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath, enumRefStringPath: ApiStringEnumRef) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery: MultiValueMap = mutableMapOf()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/path/string/{path_string}/integer/{path_integer}/{enum_nonref_string_path}/{enum_ref_string_path}".replace("{"+"path_string"+"}", encodeURIComponent(pathString.toString())).replace("{"+"path_integer"+"}", encodeURIComponent(pathInteger.toString())).replace("{"+"enum_nonref_string_path"+"}", encodeURIComponent(enumNonrefStringPath.value.toString())).replace("{"+"enum_ref_string_path"+"}", encodeURIComponent(enumRefStringPath.toString())),
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    private fun encodeURIComponent(uriComponent: kotlin.String): kotlin.String =
+        HttpUrl.Builder().scheme("http").host("localhost").addPathSegment(uriComponent).build().encodedPathSegments[0]
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/apis/QueryApi.kt

@@ -0,0 +1,557 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.apis
+
+import java.io.IOException
+import okhttp3.Call
+import okhttp3.HttpUrl
+
+import org.openapitools.client.models.ApiPet
+import org.openapitools.client.models.ApiStringEnumRef
+import org.openapitools.client.models.ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter
+
+import com.squareup.moshi.Json
+
+import org.openapitools.client.infrastructure.ApiClient
+import org.openapitools.client.infrastructure.ApiResponse
+import org.openapitools.client.infrastructure.ClientException
+import org.openapitools.client.infrastructure.ClientError
+import org.openapitools.client.infrastructure.ServerException
+import org.openapitools.client.infrastructure.ServerError
+import org.openapitools.client.infrastructure.MultiValueMap
+import org.openapitools.client.infrastructure.PartConfig
+import org.openapitools.client.infrastructure.RequestConfig
+import org.openapitools.client.infrastructure.RequestMethod
+import org.openapitools.client.infrastructure.ResponseType
+import org.openapitools.client.infrastructure.Success
+import org.openapitools.client.infrastructure.toMultiValue
+
+class QueryApi(basePath: kotlin.String = defaultBasePath, client: Call.Factory = ApiClient.defaultClient) : ApiClient(basePath, client) {
+    companion object {
+        @JvmStatic
+        val defaultBasePath: String by lazy {
+            System.getProperties().getProperty(ApiClient.baseUrlKey, "http://localhost:3000")
+        }
+    }
+
+    /**
+     * enum for parameter enumNonrefStringQuery
+     */
+     enum class EnumNonrefStringQueryTestEnumRefString(val value: kotlin.String) {
+         @Json(name = "success") success("success"),
+         @Json(name = "failure") failure("failure"),
+         @Json(name = "unclassified") unclassified("unclassified");
+
+        /**
+         * Override [toString()] to avoid using the enum variable name as the value, and instead use
+         * the actual value defined in the API spec file.
+         *
+         * This solves a problem when the variable name and its value are different, and ensures that
+         * the client sends the correct enum values to the server always.
+         */
+        override fun toString(): kotlin.String = "$value"
+     }
+
+    /**
+     * Test query parameter(s)
+     * Test query parameter(s)
+     * @param enumNonrefStringQuery  (optional)
+     * @param enumRefStringQuery  (optional)
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testEnumRefString(enumNonrefStringQuery: EnumNonrefStringQueryTestEnumRefString? = null, enumRefStringQuery: ApiStringEnumRef? = null) : kotlin.String {
+        val localVarResponse = testEnumRefStringWithHttpInfo(enumNonrefStringQuery = enumNonrefStringQuery, enumRefStringQuery = enumRefStringQuery)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test query parameter(s)
+     * Test query parameter(s)
+     * @param enumNonrefStringQuery  (optional)
+     * @param enumRefStringQuery  (optional)
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testEnumRefStringWithHttpInfo(enumNonrefStringQuery: EnumNonrefStringQueryTestEnumRefString?, enumRefStringQuery: ApiStringEnumRef?) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testEnumRefStringRequestConfig(enumNonrefStringQuery = enumNonrefStringQuery, enumRefStringQuery = enumRefStringQuery)
+
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testEnumRefString
+     *
+     * @param enumNonrefStringQuery  (optional)
+     * @param enumRefStringQuery  (optional)
+     * @return RequestConfig
+     */
+    fun testEnumRefStringRequestConfig(enumNonrefStringQuery: EnumNonrefStringQueryTestEnumRefString?, enumRefStringQuery: ApiStringEnumRef?) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery: MultiValueMap = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+            .apply {
+                if (enumNonrefStringQuery != null) {
+                    put("enum_nonref_string_query", listOf(enumNonrefStringQuery.value))
+                }
+                if (enumRefStringQuery != null) {
+                    put("enum_ref_string_query", listOf(enumRefStringQuery.toString()))
+                }
+            }
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/query/enum_ref_string",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+    /**
+     * Test query parameter(s)
+     * Test query parameter(s)
+     * @param datetimeQuery  (optional)
+     * @param dateQuery  (optional)
+     * @param stringQuery  (optional)
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testQueryDatetimeDateString(datetimeQuery: java.time.OffsetDateTime? = null, dateQuery: java.time.LocalDate? = null, stringQuery: kotlin.String? = null) : kotlin.String {
+        val localVarResponse = testQueryDatetimeDateStringWithHttpInfo(datetimeQuery = datetimeQuery, dateQuery = dateQuery, stringQuery = stringQuery)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test query parameter(s)
+     * Test query parameter(s)
+     * @param datetimeQuery  (optional)
+     * @param dateQuery  (optional)
+     * @param stringQuery  (optional)
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testQueryDatetimeDateStringWithHttpInfo(datetimeQuery: java.time.OffsetDateTime?, dateQuery: java.time.LocalDate?, stringQuery: kotlin.String?) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testQueryDatetimeDateStringRequestConfig(datetimeQuery = datetimeQuery, dateQuery = dateQuery, stringQuery = stringQuery)
+
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testQueryDatetimeDateString
+     *
+     * @param datetimeQuery  (optional)
+     * @param dateQuery  (optional)
+     * @param stringQuery  (optional)
+     * @return RequestConfig
+     */
+    fun testQueryDatetimeDateStringRequestConfig(datetimeQuery: java.time.OffsetDateTime?, dateQuery: java.time.LocalDate?, stringQuery: kotlin.String?) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery: MultiValueMap = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+            .apply {
+                if (datetimeQuery != null) {
+                    put("datetime_query", listOf(parseDateToQueryString(datetimeQuery)))
+                }
+                if (dateQuery != null) {
+                    put("date_query", listOf(parseDateToQueryString(dateQuery)))
+                }
+                if (stringQuery != null) {
+                    put("string_query", listOf(stringQuery.toString()))
+                }
+            }
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/query/datetime/date/string",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+    /**
+     * Test query parameter(s)
+     * Test query parameter(s)
+     * @param integerQuery  (optional)
+     * @param booleanQuery  (optional)
+     * @param stringQuery  (optional)
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testQueryIntegerBooleanString(integerQuery: kotlin.Int? = null, booleanQuery: kotlin.Boolean? = null, stringQuery: kotlin.String? = null) : kotlin.String {
+        val localVarResponse = testQueryIntegerBooleanStringWithHttpInfo(integerQuery = integerQuery, booleanQuery = booleanQuery, stringQuery = stringQuery)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test query parameter(s)
+     * Test query parameter(s)
+     * @param integerQuery  (optional)
+     * @param booleanQuery  (optional)
+     * @param stringQuery  (optional)
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testQueryIntegerBooleanStringWithHttpInfo(integerQuery: kotlin.Int?, booleanQuery: kotlin.Boolean?, stringQuery: kotlin.String?) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testQueryIntegerBooleanStringRequestConfig(integerQuery = integerQuery, booleanQuery = booleanQuery, stringQuery = stringQuery)
+
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testQueryIntegerBooleanString
+     *
+     * @param integerQuery  (optional)
+     * @param booleanQuery  (optional)
+     * @param stringQuery  (optional)
+     * @return RequestConfig
+     */
+    fun testQueryIntegerBooleanStringRequestConfig(integerQuery: kotlin.Int?, booleanQuery: kotlin.Boolean?, stringQuery: kotlin.String?) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery: MultiValueMap = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+            .apply {
+                if (integerQuery != null) {
+                    put("integer_query", listOf(integerQuery.toString()))
+                }
+                if (booleanQuery != null) {
+                    put("boolean_query", listOf(booleanQuery.toString()))
+                }
+                if (stringQuery != null) {
+                    put("string_query", listOf(stringQuery.toString()))
+                }
+            }
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/query/integer/boolean/string",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+    /**
+     * Test query parameter(s)
+     * Test query parameter(s)
+     * @param queryObject  (optional)
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testQueryStyleDeepObjectExplodeTrueObject(queryObject: ApiPet? = null) : kotlin.String {
+        val localVarResponse = testQueryStyleDeepObjectExplodeTrueObjectWithHttpInfo(queryObject = queryObject)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test query parameter(s)
+     * Test query parameter(s)
+     * @param queryObject  (optional)
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testQueryStyleDeepObjectExplodeTrueObjectWithHttpInfo(queryObject: ApiPet?) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testQueryStyleDeepObjectExplodeTrueObjectRequestConfig(queryObject = queryObject)
+
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testQueryStyleDeepObjectExplodeTrueObject
+     *
+     * @param queryObject  (optional)
+     * @return RequestConfig
+     */
+    fun testQueryStyleDeepObjectExplodeTrueObjectRequestConfig(queryObject: ApiPet?) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery: MultiValueMap = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+            .apply {
+                if (queryObject != null) {
+                    put("query_object", listOf(queryObject.toString()))
+                }
+            }
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/query/style_deepObject/explode_true/object",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+    /**
+     * Test query parameter(s)
+     * Test query parameter(s)
+     * @param queryObject  (optional)
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testQueryStyleFormExplodeTrueArrayString(queryObject: ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter? = null) : kotlin.String {
+        val localVarResponse = testQueryStyleFormExplodeTrueArrayStringWithHttpInfo(queryObject = queryObject)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test query parameter(s)
+     * Test query parameter(s)
+     * @param queryObject  (optional)
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testQueryStyleFormExplodeTrueArrayStringWithHttpInfo(queryObject: ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter?) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testQueryStyleFormExplodeTrueArrayStringRequestConfig(queryObject = queryObject)
+
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testQueryStyleFormExplodeTrueArrayString
+     *
+     * @param queryObject  (optional)
+     * @return RequestConfig
+     */
+    fun testQueryStyleFormExplodeTrueArrayStringRequestConfig(queryObject: ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter?) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery: MultiValueMap = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+            .apply {
+                if (queryObject != null) {
+                    put("query_object", listOf(queryObject.toString()))
+                }
+            }
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/query/style_form/explode_true/array_string",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+    /**
+     * Test query parameter(s)
+     * Test query parameter(s)
+     * @param queryObject  (optional)
+     * @return kotlin.String
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     * @throws UnsupportedOperationException If the API returns an informational or redirection response
+     * @throws ClientException If the API returns a client error response
+     * @throws ServerException If the API returns a server error response
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class, UnsupportedOperationException::class, ClientException::class, ServerException::class)
+    fun testQueryStyleFormExplodeTrueObject(queryObject: ApiPet? = null) : kotlin.String {
+        val localVarResponse = testQueryStyleFormExplodeTrueObjectWithHttpInfo(queryObject = queryObject)
+
+        return when (localVarResponse.responseType) {
+            ResponseType.Success -> (localVarResponse as Success<*>).data as kotlin.String
+            ResponseType.Informational -> throw UnsupportedOperationException("Client does not support Informational responses.")
+            ResponseType.Redirection -> throw UnsupportedOperationException("Client does not support Redirection responses.")
+            ResponseType.ClientError -> {
+                val localVarError = localVarResponse as ClientError<*>
+                throw ClientException("Client error : ${localVarError.statusCode} ${localVarError.message.orEmpty()}", localVarError.statusCode, localVarResponse)
+            }
+            ResponseType.ServerError -> {
+                val localVarError = localVarResponse as ServerError<*>
+                throw ServerException("Server error : ${localVarError.statusCode} ${localVarError.message.orEmpty()} ${localVarError.body}", localVarError.statusCode, localVarResponse)
+            }
+        }
+    }
+
+    /**
+     * Test query parameter(s)
+     * Test query parameter(s)
+     * @param queryObject  (optional)
+     * @return ApiResponse<kotlin.String?>
+     * @throws IllegalStateException If the request is not correctly configured
+     * @throws IOException Rethrows the OkHttp execute method exception
+     */
+    @Suppress("UNCHECKED_CAST")
+    @Throws(IllegalStateException::class, IOException::class)
+    fun testQueryStyleFormExplodeTrueObjectWithHttpInfo(queryObject: ApiPet?) : ApiResponse<kotlin.String?> {
+        val localVariableConfig = testQueryStyleFormExplodeTrueObjectRequestConfig(queryObject = queryObject)
+
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    /**
+     * To obtain the request config of the operation testQueryStyleFormExplodeTrueObject
+     *
+     * @param queryObject  (optional)
+     * @return RequestConfig
+     */
+    fun testQueryStyleFormExplodeTrueObjectRequestConfig(queryObject: ApiPet?) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery: MultiValueMap = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+            .apply {
+                if (queryObject != null) {
+                    put("query_object", listOf(queryObject.toString()))
+                }
+            }
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Accept"] = "text/plain"
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/query/style_form/explode_true/object",
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    private fun encodeURIComponent(uriComponent: kotlin.String): kotlin.String =
+        HttpUrl.Builder().scheme("http").host("localhost").addPathSegment(uriComponent).build().encodedPathSegments[0]
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/ApiAbstractions.kt

@@ -0,0 +1,23 @@
+package org.openapitools.client.infrastructure
+
+typealias MultiValueMap = MutableMap<String,List<String>>
+
+fun collectionDelimiter(collectionFormat: String): String = when(collectionFormat) {
+    "csv" -> ","
+    "tsv" -> "\t"
+    "pipe" -> "|"
+    "space" -> " "
+    else -> ""
+}
+
+val defaultMultiValueConverter: (item: Any?) -> String = { item -> "$item" }
+
+fun <T : Any?> toMultiValue(items: Array<T>, collectionFormat: String, map: (item: T) -> String = defaultMultiValueConverter): List<String>
+        = toMultiValue(items.asIterable(), collectionFormat, map)
+
+fun <T : Any?> toMultiValue(items: Iterable<T>, collectionFormat: String, map: (item: T) -> String = defaultMultiValueConverter): List<String> {
+    return when(collectionFormat) {
+        "multi" -> items.map(map)
+        else -> listOf(items.joinToString(separator = collectionDelimiter(collectionFormat), transform = map))
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt

@@ -0,0 +1,375 @@
+package org.openapitools.client.infrastructure
+
+import okhttp3.OkHttpClient
+import okhttp3.RequestBody
+import okhttp3.RequestBody.Companion.asRequestBody
+import okhttp3.RequestBody.Companion.toRequestBody
+import okhttp3.FormBody
+import okhttp3.HttpUrl.Companion.toHttpUrlOrNull
+import okhttp3.ResponseBody
+import okhttp3.MediaType.Companion.toMediaTypeOrNull
+import okhttp3.Request
+import okhttp3.Headers
+import okhttp3.Headers.Builder
+import okhttp3.Headers.Companion.toHeaders
+import okhttp3.MultipartBody
+import okhttp3.Call
+import okhttp3.Callback
+import okhttp3.Response
+import java.io.BufferedWriter
+import java.io.File
+import java.io.FileWriter
+import java.io.IOException
+import java.net.URLConnection
+import java.time.LocalDate
+import java.time.LocalDateTime
+import java.time.LocalTime
+import java.time.OffsetDateTime
+import java.time.OffsetTime
+import java.util.Locale
+import java.util.regex.Pattern
+import com.squareup.moshi.adapter
+
+val EMPTY_REQUEST: RequestBody = ByteArray(0).toRequestBody()
+
+open class ApiClient(val baseUrl: String, val client: Call.Factory = defaultClient) {
+    companion object {
+        protected const val ContentType: String = "Content-Type"
+        protected const val Accept: String = "Accept"
+        protected const val Authorization: String = "Authorization"
+        protected const val JsonMediaType: String = "application/json"
+        protected const val FormDataMediaType: String = "multipart/form-data"
+        protected const val FormUrlEncMediaType: String = "application/x-www-form-urlencoded"
+        protected const val XmlMediaType: String = "application/xml"
+        protected const val OctetMediaType: String = "application/octet-stream"
+        protected const val TextMediaType: String = "text/plain"
+
+        val apiKey: MutableMap<String, String> = mutableMapOf()
+        val apiKeyPrefix: MutableMap<String, String> = mutableMapOf()
+        var username: String? = null
+        var password: String? = null
+        var accessToken: String? = null
+        const val baseUrlKey: String = "org.openapitools.client.baseUrl"
+
+        @JvmStatic
+        val defaultClient: OkHttpClient by lazy {
+            builder.build()
+        }
+
+        @JvmStatic
+        val builder: OkHttpClient.Builder = OkHttpClient.Builder()
+    }
+
+    /**
+     * Guess Content-Type header from the given byteArray (defaults to "application/octet-stream").
+     *
+     * @param byteArray The given file
+     * @return The guessed Content-Type
+     */
+    protected fun guessContentTypeFromByteArray(byteArray: ByteArray): String {
+        val contentType = try {
+            URLConnection.guessContentTypeFromStream(byteArray.inputStream())
+        } catch (io: IOException) {
+            "application/octet-stream"
+        }
+        return contentType
+    }
+
+    /**
+     * Guess Content-Type header from the given file (defaults to "application/octet-stream").
+     *
+     * @param file The given file
+     * @return The guessed Content-Type
+     */
+    protected fun guessContentTypeFromFile(file: File): String {
+        val contentType = URLConnection.guessContentTypeFromName(file.name)
+        return contentType ?: "application/octet-stream"
+    }
+
+    /**
+     * Adds a File to a MultipartBody.Builder
+     * Defined a helper in the requestBody method to not duplicate code
+     * It will be used when the content is a FormDataMediaType and the body of the PartConfig is a File
+     *
+     * @param name The field name to add in the request
+     * @param headers The headers that are in the PartConfig
+     * @param file The file that will be added as the field value
+     * @return The method returns Unit but the new Part is added to the Builder that the extension function is applying on
+     * @see requestBody
+     */
+    protected fun MultipartBody.Builder.addPartToMultiPart(name: String, headers: Map<String, String>, file: File) {
+        val partHeaders = headers.toMutableMap() +
+            ("Content-Disposition" to "form-data; name=\"$name\"; filename=\"${file.name}\"")
+        val fileMediaType = guessContentTypeFromFile(file).toMediaTypeOrNull()
+        addPart(
+            partHeaders.toHeaders(),
+            file.asRequestBody(fileMediaType)
+        )
+    }
+
+    /**
+     * Adds any type to a MultipartBody.Builder
+     * Defined a helper in the requestBody method to not duplicate code
+     * It will be used when the content is a FormDataMediaType and the body of the PartConfig is not a File.
+     *
+     * @param name The field name to add in the request
+     * @param headers The headers that are in the PartConfig
+     * @param obj The field name to add in the request
+     * @return The method returns Unit but the new Part is added to the Builder that the extension function is applying on
+     * @see requestBody
+     */
+    protected fun <T> MultipartBody.Builder.addPartToMultiPart(name: String, headers: Map<String, String>, obj: T?) {
+        val partHeaders = headers.toMutableMap() +
+            ("Content-Disposition" to "form-data; name=\"$name\"")
+        addPart(
+            partHeaders.toHeaders(),
+            parameterToString(obj).toRequestBody(null)
+        )
+    }
+
+    protected inline fun <reified T> requestBody(content: T, mediaType: String?): RequestBody =
+        when {
+            content is ByteArray -> content.toRequestBody((mediaType ?: guessContentTypeFromByteArray(content)).toMediaTypeOrNull())
+            content is File -> content.asRequestBody((mediaType ?: guessContentTypeFromFile(content)).toMediaTypeOrNull())
+            mediaType == FormDataMediaType ->
+                MultipartBody.Builder()
+                    .setType(MultipartBody.FORM)
+                    .apply {
+                        // content's type *must* be Map<String, PartConfig<*>>
+                        @Suppress("UNCHECKED_CAST")
+                        (content as Map<String, PartConfig<*>>).forEach { (name, part) ->
+                            when (part.body) {
+                                is File -> addPartToMultiPart(name, part.headers, part.body)
+                                is List<*> -> {
+                                    part.body.forEach {
+                                        if (it is File) {
+                                            addPartToMultiPart(name, part.headers, it)
+                                        } else {
+                                            addPartToMultiPart(name, part.headers, it)
+                                        }
+                                    }
+                               }
+                               else -> addPartToMultiPart(name, part.headers, part.body)
+                            }
+                        }
+                    }.build()
+            mediaType == FormUrlEncMediaType -> {
+                FormBody.Builder().apply {
+                    // content's type *must* be Map<String, PartConfig<*>>
+                    @Suppress("UNCHECKED_CAST")
+                    (content as Map<String, PartConfig<*>>).forEach { (name, part) ->
+                        add(name, parameterToString(part.body))
+                    }
+                }.build()
+            }
+            mediaType == null || mediaType.startsWith("application/") && mediaType.endsWith("json") ->
+                if (content == null) {
+                    EMPTY_REQUEST
+                } else {
+                    Serializer.moshi.adapter(T::class.java).toJson(content)
+                        .toRequestBody((mediaType ?: JsonMediaType).toMediaTypeOrNull())
+                }
+            mediaType == XmlMediaType -> throw UnsupportedOperationException("xml not currently supported.")
+            mediaType == TextMediaType && content is String ->
+                content.toRequestBody(TextMediaType.toMediaTypeOrNull())
+            // TODO: this should be extended with other serializers
+            else -> throw UnsupportedOperationException("requestBody currently only supports JSON body, text body, byte body and File body.")
+        }
+
+    @OptIn(ExperimentalStdlibApi::class)
+    protected inline fun <reified T: Any?> responseBody(response: Response, mediaType: String? = JsonMediaType): T? {
+        val body = response.body
+        if(body == null) {
+            return null
+        } else if (T::class.java == Unit::class.java) {
+            // No need to parse the body when we're not interested in the body
+            // Useful when API is returning other Content-Type
+            return null
+        } else if (T::class.java == File::class.java) {
+            // return tempFile
+            val contentDisposition = response.header("Content-Disposition")
+
+            val fileName = if (contentDisposition != null) {
+                // Get filename from the Content-Disposition header.
+                val pattern = Pattern.compile("filename=['\"]?([^'\"\\s]+)['\"]?")
+                val matcher = pattern.matcher(contentDisposition)
+                if (matcher.find()) {
+                    matcher.group(1)
+                        ?.replace(".*[/\\\\]", "")
+                        ?.replace(";", "")
+                } else {
+                    null
+                }
+            } else {
+                null
+            }
+
+            var prefix: String?
+            val suffix: String?
+            if (fileName == null) {
+                prefix = "download"
+                suffix = ""
+            } else {
+                val pos = fileName.lastIndexOf(".")
+                if (pos == -1) {
+                    prefix = fileName
+                    suffix = null
+                } else {
+                    prefix = fileName.substring(0, pos)
+                    suffix = fileName.substring(pos)
+                }
+                // Files.createTempFile requires the prefix to be at least three characters long
+                if (prefix.length < 3) {
+                    prefix = "download"
+                }
+            }
+
+            // Attention: if you are developing an android app that supports API Level 25 and below, please check flag supportAndroidApiLevel25AndBelow in https://openapi-generator.tech/docs/generators/kotlin#config-options
+            val tempFile = java.nio.file.Files.createTempFile(prefix, suffix).toFile()
+            tempFile.deleteOnExit()
+            body.byteStream().use { inputStream ->
+                tempFile.outputStream().use { tempFileOutputStream ->
+                    inputStream.copyTo(tempFileOutputStream)
+                }
+            }
+            return tempFile as T
+        }
+
+        return when {
+            mediaType == null || (mediaType.startsWith("application/") && mediaType.endsWith("json")) -> {
+                val bodyContent = body.string()
+                if (bodyContent.isEmpty()) {
+                    return null
+                }
+                Serializer.moshi.adapter<T>().fromJson(bodyContent)
+            }
+            mediaType == OctetMediaType -> body.bytes() as? T
+            mediaType == TextMediaType -> body.string() as? T
+            else ->  throw UnsupportedOperationException("responseBody currently only supports JSON body, text body and byte body.")
+        }
+    }
+
+    protected fun <T> updateAuthParams(requestConfig: RequestConfig<T>) {
+        if (requestConfig.headers[Authorization].isNullOrEmpty()) {
+            username?.let { username ->
+                password?.let { password ->
+                    requestConfig.headers[Authorization] = okhttp3.Credentials.basic(username, password)
+                }
+            }
+        }
+        if (requestConfig.headers[Authorization].isNullOrEmpty()) {
+            accessToken?.let { accessToken ->
+                requestConfig.headers[Authorization] = "Bearer $accessToken"
+            }
+        }
+    }
+
+    protected inline fun <reified I, reified T: Any?> request(requestConfig: RequestConfig<I>): ApiResponse<T?> {
+        val httpUrl = baseUrl.toHttpUrlOrNull() ?: throw IllegalStateException("baseUrl is invalid.")
+
+        // take authMethod from operation
+        updateAuthParams(requestConfig)
+
+        val url = httpUrl.newBuilder()
+            .addEncodedPathSegments(requestConfig.path.trimStart('/'))
+            .apply {
+                requestConfig.query.forEach { query ->
+                    query.value.forEach { queryValue ->
+                        addQueryParameter(query.key, queryValue)
+                    }
+                }
+            }.build()
+
+        // take content-type/accept from spec or set to default (application/json) if not defined
+        if (requestConfig.body != null && requestConfig.headers[ContentType].isNullOrEmpty()) {
+            requestConfig.headers[ContentType] = JsonMediaType
+        }
+        if (requestConfig.headers[Accept].isNullOrEmpty()) {
+            requestConfig.headers[Accept] = JsonMediaType
+        }
+        val headers = requestConfig.headers
+
+        if (headers[Accept].isNullOrEmpty()) {
+            throw kotlin.IllegalStateException("Missing Accept header. This is required.")
+        }
+
+        val contentType = if (headers[ContentType] != null) {
+            // TODO: support multiple contentType options here.
+            (headers[ContentType] as String).substringBefore(";").lowercase(Locale.US)
+        } else {
+            null
+        }
+
+        val request = when (requestConfig.method) {
+            RequestMethod.DELETE -> Request.Builder().url(url).delete(requestBody(requestConfig.body, contentType))
+            RequestMethod.GET -> Request.Builder().url(url)
+            RequestMethod.HEAD -> Request.Builder().url(url).head()
+            RequestMethod.PATCH -> Request.Builder().url(url).patch(requestBody(requestConfig.body, contentType))
+            RequestMethod.PUT -> Request.Builder().url(url).put(requestBody(requestConfig.body, contentType))
+            RequestMethod.POST -> Request.Builder().url(url).post(requestBody(requestConfig.body, contentType))
+            RequestMethod.OPTIONS -> Request.Builder().url(url).method("OPTIONS", null)
+        }.apply {
+            val headersBuilder = Headers.Builder()
+            headers.forEach { header ->
+                headersBuilder.add(header.key, header.value)
+            }
+            this.headers(headersBuilder.build())
+        }.build()
+
+        val response = client.newCall(request).execute()
+
+        val accept = response.header(ContentType)?.substringBefore(";")?.lowercase(Locale.US)
+
+        // TODO: handle specific mapping types. e.g. Map<int, Class<?>>
+        @Suppress("UNNECESSARY_SAFE_CALL")
+        return response.use {
+            when {
+                it.isRedirect -> Redirection(
+                    it.code,
+                    it.headers.toMultimap()
+                )
+                it.isInformational -> Informational(
+                    it.message,
+                    it.code,
+                    it.headers.toMultimap()
+                )
+                it.isSuccessful -> Success(
+                    responseBody(it, accept),
+                    it.code,
+                    it.headers.toMultimap()
+                )
+                it.isClientError -> ClientError(
+                    it.message,
+                    it.body?.string(),
+                    it.code,
+                    it.headers.toMultimap()
+                )
+                else -> ServerError(
+                    it.message,
+                    it.body?.string(),
+                    it.code,
+                    it.headers.toMultimap()
+                )
+            }
+        }
+    }
+
+    protected fun parameterToString(value: Any?): String = when (value) {
+        null -> ""
+        is Array<*> -> toMultiValue(value, "csv").toString()
+        is Iterable<*> -> toMultiValue(value, "csv").toString()
+        is OffsetDateTime, is OffsetTime, is LocalDateTime, is LocalDate, is LocalTime ->
+            parseDateToQueryString(value)
+        else -> value.toString()
+    }
+
+    protected inline fun <reified T: Any> parseDateToQueryString(value : T): String {
+        /*
+        .replace("\"", "") converts the json object string to an actual string for the query parameter.
+        The moshi or gson adapter allows a more generic solution instead of trying to use a native
+        formatter. It also easily allows to provide a simple way to define a custom date format pattern
+        inside a gson/moshi adapter.
+        */
+        return Serializer.moshi.adapter(T::class.java).toJson(value).replace("\"", "")
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/ApiResponse.kt

@@ -0,0 +1,43 @@
+package org.openapitools.client.infrastructure
+
+enum class ResponseType {
+    Success, Informational, Redirection, ClientError, ServerError
+}
+
+interface Response
+
+abstract class ApiResponse<T>(val responseType: ResponseType): Response {
+    abstract val statusCode: Int
+    abstract val headers: Map<String,List<String>>
+}
+
+class Success<T>(
+    val data: T,
+    override val statusCode: Int = -1,
+    override val headers: Map<String, List<String>> = mapOf()
+): ApiResponse<T>(ResponseType.Success)
+
+class Informational<T>(
+    val statusText: String,
+    override val statusCode: Int = -1,
+    override val headers: Map<String, List<String>> = mapOf()
+) : ApiResponse<T>(ResponseType.Informational)
+
+class Redirection<T>(
+    override val statusCode: Int = -1,
+    override val headers: Map<String, List<String>> = mapOf()
+) : ApiResponse<T>(ResponseType.Redirection)
+
+class ClientError<T>(
+    val message: String? = null,
+    val body: Any? = null,
+    override val statusCode: Int = -1,
+    override val headers: Map<String, List<String>> = mapOf()
+) : ApiResponse<T>(ResponseType.ClientError)
+
+class ServerError<T>(
+    val message: String? = null,
+    val body: Any? = null,
+    override val statusCode: Int = -1,
+    override val headers: Map<String, List<String>> = mapOf()
+): ApiResponse<T>(ResponseType.ServerError)

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/BigDecimalAdapter.kt

@@ -0,0 +1,17 @@
+package org.openapitools.client.infrastructure
+
+import com.squareup.moshi.FromJson
+import com.squareup.moshi.ToJson
+import java.math.BigDecimal
+
+class BigDecimalAdapter {
+    @ToJson
+    fun toJson(value: BigDecimal): String {
+        return value.toPlainString()
+    }
+
+    @FromJson
+    fun fromJson(value: String): BigDecimal {
+        return BigDecimal(value)
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/BigIntegerAdapter.kt

@@ -0,0 +1,17 @@
+package org.openapitools.client.infrastructure
+
+import com.squareup.moshi.FromJson
+import com.squareup.moshi.ToJson
+import java.math.BigInteger
+
+class BigIntegerAdapter {
+    @ToJson
+    fun toJson(value: BigInteger): String {
+        return value.toString()
+    }
+
+    @FromJson
+    fun fromJson(value: String): BigInteger {
+        return BigInteger(value)
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/ByteArrayAdapter.kt

@@ -0,0 +1,12 @@
+package org.openapitools.client.infrastructure
+
+import com.squareup.moshi.FromJson
+import com.squareup.moshi.ToJson
+
+class ByteArrayAdapter {
+    @ToJson
+    fun toJson(data: ByteArray): String = String(data)
+
+    @FromJson
+    fun fromJson(data: String): ByteArray = data.toByteArray()
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/Errors.kt

@@ -0,0 +1,18 @@
+@file:Suppress("unused")
+package org.openapitools.client.infrastructure
+
+import java.lang.RuntimeException
+
+open class ClientException(message: kotlin.String? = null, val statusCode: Int = -1, val response: Response? = null) : RuntimeException(message) {
+
+    companion object {
+        private const val serialVersionUID: Long = 123L
+    }
+}
+
+open class ServerException(message: kotlin.String? = null, val statusCode: Int = -1, val response: Response? = null) : RuntimeException(message) {
+
+    companion object {
+        private const val serialVersionUID: Long = 456L
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/LocalDateAdapter.kt

@@ -0,0 +1,19 @@
+package org.openapitools.client.infrastructure
+
+import com.squareup.moshi.FromJson
+import com.squareup.moshi.ToJson
+import java.time.LocalDate
+import java.time.format.DateTimeFormatter
+
+class LocalDateAdapter {
+    @ToJson
+    fun toJson(value: LocalDate): String {
+        return DateTimeFormatter.ISO_LOCAL_DATE.format(value)
+    }
+
+    @FromJson
+    fun fromJson(value: String): LocalDate {
+        return LocalDate.parse(value, DateTimeFormatter.ISO_LOCAL_DATE)
+    }
+
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/LocalDateTimeAdapter.kt

@@ -0,0 +1,19 @@
+package org.openapitools.client.infrastructure
+
+import com.squareup.moshi.FromJson
+import com.squareup.moshi.ToJson
+import java.time.LocalDateTime
+import java.time.format.DateTimeFormatter
+
+class LocalDateTimeAdapter {
+    @ToJson
+    fun toJson(value: LocalDateTime): String {
+        return DateTimeFormatter.ISO_LOCAL_DATE_TIME.format(value)
+    }
+
+    @FromJson
+    fun fromJson(value: String): LocalDateTime {
+        return LocalDateTime.parse(value, DateTimeFormatter.ISO_LOCAL_DATE_TIME)
+    }
+
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/OffsetDateTimeAdapter.kt

@@ -0,0 +1,19 @@
+package org.openapitools.client.infrastructure
+
+import com.squareup.moshi.FromJson
+import com.squareup.moshi.ToJson
+import java.time.OffsetDateTime
+import java.time.format.DateTimeFormatter
+
+class OffsetDateTimeAdapter {
+    @ToJson
+    fun toJson(value: OffsetDateTime): String {
+        return DateTimeFormatter.ISO_OFFSET_DATE_TIME.format(value)
+    }
+
+    @FromJson
+    fun fromJson(value: String): OffsetDateTime {
+        return OffsetDateTime.parse(value, DateTimeFormatter.ISO_OFFSET_DATE_TIME)
+    }
+
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/PartConfig.kt

@@ -0,0 +1,11 @@
+package org.openapitools.client.infrastructure
+
+/**
+ * Defines a config object for a given part of a multi-part request.
+ * NOTE: Headers is a Map<String,String> because rfc2616 defines
+ *       multi-valued headers as csv-only.
+ */
+data class PartConfig<T>(
+    val headers: MutableMap<String, String> = mutableMapOf(),
+    val body: T? = null
+)

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/RequestConfig.kt

@@ -0,0 +1,19 @@
+package org.openapitools.client.infrastructure
+
+/**
+ * Defines a config object for a given request.
+ * NOTE: This object doesn't include 'body' because it
+ *       allows for caching of the constructed object
+ *       for many request definitions.
+ * NOTE: Headers is a Map<String,String> because rfc2616 defines
+ *       multi-valued headers as csv-only.
+ */
+data class RequestConfig<T>(
+    val method: RequestMethod,
+    val path: String,
+    val headers: MutableMap<String, String> = mutableMapOf(),
+    val params: MutableMap<String, Any> = mutableMapOf(),
+    val query: MutableMap<String, List<String>> = mutableMapOf(),
+    val requiresAuthentication: Boolean,
+    val body: T? = null
+)

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/RequestMethod.kt

@@ -0,0 +1,8 @@
+package org.openapitools.client.infrastructure
+
+/**
+ * Provides enumerated HTTP verbs
+ */
+enum class RequestMethod {
+    GET, DELETE, HEAD, OPTIONS, PATCH, POST, PUT
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/ResponseExtensions.kt

@@ -0,0 +1,24 @@
+package org.openapitools.client.infrastructure
+
+import okhttp3.Response
+
+/**
+ * Provides an extension to evaluation whether the response is a 1xx code
+ */
+val Response.isInformational : Boolean get() = this.code in 100..199
+
+/**
+ * Provides an extension to evaluation whether the response is a 3xx code
+ */
+@Suppress("EXTENSION_SHADOWED_BY_MEMBER")
+val Response.isRedirect : Boolean get() = this.code in 300..399
+
+/**
+ * Provides an extension to evaluation whether the response is a 4xx code
+ */
+val Response.isClientError : Boolean get() = this.code in 400..499
+
+/**
+ * Provides an extension to evaluation whether the response is a 5xx (Standard) through 999 (non-standard) code
+ */
+val Response.isServerError : Boolean get() = this.code in 500..999

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/Serializer.kt

@@ -0,0 +1,23 @@
+package org.openapitools.client.infrastructure
+
+import com.squareup.moshi.Moshi
+import com.squareup.moshi.kotlin.reflect.KotlinJsonAdapterFactory
+
+object Serializer {
+    @JvmStatic
+    val moshiBuilder: Moshi.Builder = Moshi.Builder()
+        .add(OffsetDateTimeAdapter())
+        .add(LocalDateTimeAdapter())
+        .add(LocalDateAdapter())
+        .add(UUIDAdapter())
+        .add(ByteArrayAdapter())
+        .add(URIAdapter())
+        .add(KotlinJsonAdapterFactory())
+        .add(BigDecimalAdapter())
+        .add(BigIntegerAdapter())
+
+    @JvmStatic
+    val moshi: Moshi by lazy {
+        moshiBuilder.build()
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/URIAdapter.kt

@@ -0,0 +1,13 @@
+package org.openapitools.client.infrastructure
+
+import com.squareup.moshi.FromJson
+import com.squareup.moshi.ToJson
+import java.net.URI
+
+class URIAdapter {
+    @ToJson
+    fun toJson(uri: URI): String = uri.toString()
+
+    @FromJson
+    fun fromJson(s: String): URI = URI.create(s)
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/UUIDAdapter.kt

@@ -0,0 +1,13 @@
+package org.openapitools.client.infrastructure
+
+import com.squareup.moshi.FromJson
+import com.squareup.moshi.ToJson
+import java.util.UUID
+
+class UUIDAdapter {
+    @ToJson
+    fun toJson(uuid: UUID): String = uuid.toString()
+
+    @FromJson
+    fun fromJson(s: String): UUID = UUID.fromString(s)
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/models/ApiBird.kt

@@ -0,0 +1,42 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+
+import com.squareup.moshi.Json
+import com.squareup.moshi.JsonClass
+
+/**
+ * 
+ *
+ * @param propertySize 
+ * @param color 
+ */
+
+
+data class ApiBird (
+
+    @Json(name = "size")
+    val propertySize: kotlin.String? = null,
+
+    @Json(name = "color")
+    val color: kotlin.String? = null
+
+) {
+
+
+}
+

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/models/ApiCategory.kt

@@ -0,0 +1,42 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+
+import com.squareup.moshi.Json
+import com.squareup.moshi.JsonClass
+
+/**
+ * 
+ *
+ * @param id 
+ * @param name 
+ */
+
+
+data class ApiCategory (
+
+    @Json(name = "id")
+    val id: kotlin.Long? = null,
+
+    @Json(name = "name")
+    val name: kotlin.String? = null
+
+) {
+
+
+}
+

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/models/ApiDefaultValue.kt

@@ -0,0 +1,78 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+import org.openapitools.client.models.ApiStringEnumRef
+
+import com.squareup.moshi.Json
+import com.squareup.moshi.JsonClass
+
+/**
+ * to test the default value of properties
+ *
+ * @param arrayStringEnumRefDefault 
+ * @param arrayStringEnumDefault 
+ * @param arrayStringDefault 
+ * @param arrayIntegerDefault 
+ * @param arrayString 
+ * @param arrayStringNullable 
+ * @param arrayStringExtensionNullable 
+ * @param stringNullable 
+ */
+
+
+data class ApiDefaultValue (
+
+    @Json(name = "array_string_enum_ref_default")
+    val arrayStringEnumRefDefault: kotlin.collections.List<ApiStringEnumRef>? = null,
+
+    @Json(name = "array_string_enum_default")
+    val arrayStringEnumDefault: kotlin.collections.List<ApiDefaultValue.ArrayStringEnumDefault>? = null,
+
+    @Json(name = "array_string_default")
+    val arrayStringDefault: kotlin.collections.List<kotlin.String>? = arrayListOf("failure","skipped"),
+
+    @Json(name = "array_integer_default")
+    val arrayIntegerDefault: kotlin.collections.List<kotlin.Int>? = arrayListOf(1,3),
+
+    @Json(name = "array_string")
+    val arrayString: kotlin.collections.List<kotlin.String>? = null,
+
+    @Json(name = "array_string_nullable")
+    val arrayStringNullable: kotlin.collections.List<kotlin.String>? = null,
+
+    @Json(name = "array_string_extension_nullable")
+    val arrayStringExtensionNullable: kotlin.collections.List<kotlin.String>? = null,
+
+    @Json(name = "string_nullable")
+    val stringNullable: kotlin.String? = null
+
+) {
+
+    /**
+     * 
+     *
+     * Values: success,failure,unclassified
+     */
+    @JsonClass(generateAdapter = false)
+    enum class ArrayStringEnumDefault(val value: kotlin.String) {
+        @Json(name = "success") success("success"),
+        @Json(name = "failure") failure("failure"),
+        @Json(name = "unclassified") unclassified("unclassified");
+    }
+
+}
+

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/models/ApiNumberPropertiesOnly.kt

@@ -0,0 +1,46 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+
+import com.squareup.moshi.Json
+import com.squareup.moshi.JsonClass
+
+/**
+ * 
+ *
+ * @param number 
+ * @param float 
+ * @param double 
+ */
+
+
+data class ApiNumberPropertiesOnly (
+
+    @Json(name = "number")
+    val number: java.math.BigDecimal? = null,
+
+    @Json(name = "float")
+    val float: kotlin.Float? = null,
+
+    @Json(name = "double")
+    val double: kotlin.Double? = null
+
+) {
+
+
+}
+

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/models/ApiPet.kt

@@ -0,0 +1,72 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+import org.openapitools.client.models.ApiCategory
+import org.openapitools.client.models.ApiTag
+
+import com.squareup.moshi.Json
+import com.squareup.moshi.JsonClass
+
+/**
+ * 
+ *
+ * @param name 
+ * @param photoUrls 
+ * @param id 
+ * @param category 
+ * @param tags 
+ * @param status pet status in the store
+ */
+
+
+data class ApiPet (
+
+    @Json(name = "name")
+    val name: kotlin.String,
+
+    @Json(name = "photoUrls")
+    val photoUrls: kotlin.collections.List<kotlin.String>,
+
+    @Json(name = "id")
+    val id: kotlin.Long? = null,
+
+    @Json(name = "category")
+    val category: ApiCategory? = null,
+
+    @Json(name = "tags")
+    val tags: kotlin.collections.List<ApiTag>? = null,
+
+    /* pet status in the store */
+    @Json(name = "status")
+    val status: ApiPet.Status? = null
+
+) {
+
+    /**
+     * pet status in the store
+     *
+     * Values: available,pending,sold
+     */
+    @JsonClass(generateAdapter = false)
+    enum class Status(val value: kotlin.String) {
+        @Json(name = "available") available("available"),
+        @Json(name = "pending") pending("pending"),
+        @Json(name = "sold") sold("sold");
+    }
+
+}
+

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/models/ApiQuery.kt

@@ -0,0 +1,54 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+
+import com.squareup.moshi.Json
+import com.squareup.moshi.JsonClass
+
+/**
+ * 
+ *
+ * @param id Query
+ * @param outcomes 
+ */
+
+
+data class ApiQuery (
+
+    /* Query */
+    @Json(name = "id")
+    val id: kotlin.Long? = null,
+
+    @Json(name = "outcomes")
+    val outcomes: kotlin.collections.List<ApiQuery.Outcomes>? = null
+
+) {
+
+    /**
+     * 
+     *
+     * Values: SUCCESS,FAILURE,SKIPPED
+     */
+    @JsonClass(generateAdapter = false)
+    enum class Outcomes(val value: kotlin.String) {
+        @Json(name = "SUCCESS") SUCCESS("SUCCESS"),
+        @Json(name = "FAILURE") FAILURE("FAILURE"),
+        @Json(name = "SKIPPED") SKIPPED("SKIPPED");
+    }
+
+}
+

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/models/ApiStringEnumRef.kt

@@ -0,0 +1,66 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+
+import com.squareup.moshi.Json
+import com.squareup.moshi.JsonClass
+
+/**
+ * 
+ *
+ * Values: success,failure,unclassified
+ */
+
+@JsonClass(generateAdapter = false)
+enum class ApiStringEnumRef(val value: kotlin.String) {
+
+    @Json(name = "success")
+    success("success"),
+
+    @Json(name = "failure")
+    failure("failure"),
+
+    @Json(name = "unclassified")
+    unclassified("unclassified");
+
+    /**
+     * Override [toString()] to avoid using the enum variable name as the value, and instead use
+     * the actual value defined in the API spec file.
+     *
+     * This solves a problem when the variable name and its value are different, and ensures that
+     * the client sends the correct enum values to the server always.
+     */
+    override fun toString(): kotlin.String = value
+
+    companion object {
+        /**
+         * Converts the provided [data] to a [String] on success, null otherwise.
+         */
+        fun encode(data: kotlin.Any?): kotlin.String? = if (data is ApiStringEnumRef) "$data" else null
+
+        /**
+         * Returns a valid [ApiStringEnumRef] for [data], null otherwise.
+         */
+        fun decode(data: kotlin.Any?): ApiStringEnumRef? = data?.let {
+          val normalizedData = "$it".lowercase()
+          values().firstOrNull { value ->
+            it == value || normalizedData == "$value".lowercase()
+          }
+        }
+    }
+}
+

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/models/ApiTag.kt

@@ -0,0 +1,42 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+
+import com.squareup.moshi.Json
+import com.squareup.moshi.JsonClass
+
+/**
+ * 
+ *
+ * @param id 
+ * @param name 
+ */
+
+
+data class ApiTag (
+
+    @Json(name = "id")
+    val id: kotlin.Long? = null,
+
+    @Json(name = "name")
+    val name: kotlin.String? = null
+
+) {
+
+
+}
+

samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/models/ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter.kt

@@ -0,0 +1,38 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+
+import com.squareup.moshi.Json
+import com.squareup.moshi.JsonClass
+
+/**
+ * 
+ *
+ * @param propertyValues 
+ */
+
+
+data class ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter (
+
+    @Json(name = "values")
+    val propertyValues: kotlin.collections.List<kotlin.String>? = null
+
+) {
+
+
+}
+

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/CustomTests.kt

@@ -0,0 +1,80 @@
+package org.openapitools.client
+
+import io.kotlintest.matchers.string.shouldContain
+import io.kotlintest.specs.ShouldSpec
+import org.junit.jupiter.api.Assertions
+import org.openapitools.client.apis.BodyApi
+import java.io.File
+import java.io.FileWriter
+
+class CustomTests : ShouldSpec({
+    val bodyApi = BodyApi()
+
+    should("send a single file as null") {
+        val result = bodyApi.testBodyMultipartFormdataSingleBinary(null)
+        val parsedResult = EchoServerResponseParser(result)
+
+        parsedResult.body shouldContain """
+            Content-Disposition: form-data; name="my-file"
+            Content-Length: 0
+        """.trimIndent()
+    }
+
+    should("send a single file") {
+        val result = bodyApi.testBodyMultipartFormdataSingleBinary(createTestFile())
+        val parsedResult = EchoServerResponseParser(result)
+
+        parsedResult.body shouldContain """
+            Content-Disposition: form-data; name="my-file"; filename="test.txt"
+            Content-Type: text/plain
+            Content-Length: 12
+            
+            testing only
+        """.trimIndent()
+    }
+
+    should("send several files") {
+        val result = bodyApi.testBodyMultipartFormdataArrayOfBinary(listOf(createTestFile(), createOtherTestFile()))
+        val parsedResult = EchoServerResponseParser(result)
+
+        parsedResult.body shouldContain """
+            Content-Disposition: form-data; name="files"; filename="test.txt"
+            Content-Type: text/plain
+            Content-Length: 12
+            
+            testing only
+        """.trimIndent()
+
+        parsedResult.body shouldContain """
+            Content-Disposition: form-data; name="files"; filename="otherTestFile.txt"
+            Content-Type: text/plain
+            Content-Length: 17
+
+            Another test file
+        """.trimIndent()
+    }
+})
+
+private fun createTestFile(): File {
+    val myFile = File("test.txt")
+    if (!myFile.exists()) {
+        Assertions.assertTrue(myFile.createNewFile())
+    }
+    val fw = FileWriter(myFile)
+    fw.write("testing only")
+    fw.close()
+    myFile.deleteOnExit()
+    return myFile
+}
+
+private fun createOtherTestFile(): File {
+    val myFile = File("otherTestFile.txt")
+    if (!myFile.exists()) {
+        Assertions.assertTrue(myFile.createNewFile())
+    }
+    val fw = FileWriter(myFile)
+    fw.write("Another test file")
+    fw.close()
+    myFile.deleteOnExit()
+    return myFile
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/EchoServerResponseParser.kt

@@ -0,0 +1,44 @@
+package org.openapitools.client
+
+class EchoServerResponseParser(response: String) {
+    lateinit var method: String
+    lateinit var path: String
+    lateinit var protocol: String
+    val headers = hashMapOf<String, String>()
+    val body: String
+
+    init {
+        require(response.isNotEmpty()) { "Echo server response cannot be null" }
+
+        val lines = response.lineSequence().iterator()
+        var firstLine = true
+        var bodyStart = false
+        val bodyBuilder = StringBuilder()
+        for (line in lines) {
+            if (firstLine) {
+                val items = line.split(" ")
+                method = items[0]
+                path = items[1]
+                protocol = items[2]
+                firstLine = false
+                continue
+            }
+            if (bodyStart) {
+                bodyBuilder.append(line)
+                bodyBuilder.append("\n")
+            }
+            if (line.isEmpty()) {
+                bodyStart = true
+                continue
+            }
+
+            val keyValue = line.split(": ")
+            if (keyValue.size == 2) {
+                headers[keyValue[0]] = keyValue[1]
+            }
+        }
+        body = bodyBuilder.toString().trimEnd()
+    }
+}
+
+

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/apis/AuthApiTest.kt

@@ -0,0 +1,43 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.apis
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.apis.AuthApi
+
+class AuthApiTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of AuthApi
+        //val apiInstance = AuthApi()
+
+        // to test testAuthHttpBasic
+        should("test testAuthHttpBasic") {
+            // uncomment below to test testAuthHttpBasic
+            //val result : kotlin.String = apiInstance.testAuthHttpBasic()
+            //result shouldBe ("TODO")
+        }
+
+        // to test testAuthHttpBearer
+        should("test testAuthHttpBearer") {
+            // uncomment below to test testAuthHttpBearer
+            //val result : kotlin.String = apiInstance.testAuthHttpBearer()
+            //result shouldBe ("TODO")
+        }
+
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/apis/BodyApiTest.kt

@@ -0,0 +1,94 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.apis
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.apis.BodyApi
+import org.openapitools.client.models.ApiPet
+import org.openapitools.client.models.ApiTag
+
+class BodyApiTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of BodyApi
+        //val apiInstance = BodyApi()
+
+        // to test testBinaryGif
+        should("test testBinaryGif") {
+            // uncomment below to test testBinaryGif
+            //val result : java.io.File = apiInstance.testBinaryGif()
+            //result shouldBe ("TODO")
+        }
+
+        // to test testBodyApplicationOctetstreamBinary
+        should("test testBodyApplicationOctetstreamBinary") {
+            // uncomment below to test testBodyApplicationOctetstreamBinary
+            //val body : java.io.File = BINARY_DATA_HERE // java.io.File | 
+            //val result : kotlin.String = apiInstance.testBodyApplicationOctetstreamBinary(body)
+            //result shouldBe ("TODO")
+        }
+
+        // to test testBodyMultipartFormdataArrayOfBinary
+        should("test testBodyMultipartFormdataArrayOfBinary") {
+            // uncomment below to test testBodyMultipartFormdataArrayOfBinary
+            //val files : kotlin.collections.List<java.io.File> = /path/to/file.txt // kotlin.collections.List<java.io.File> | 
+            //val result : kotlin.String = apiInstance.testBodyMultipartFormdataArrayOfBinary(files)
+            //result shouldBe ("TODO")
+        }
+
+        // to test testBodyMultipartFormdataSingleBinary
+        should("test testBodyMultipartFormdataSingleBinary") {
+            // uncomment below to test testBodyMultipartFormdataSingleBinary
+            //val myFile : java.io.File = BINARY_DATA_HERE // java.io.File | 
+            //val result : kotlin.String = apiInstance.testBodyMultipartFormdataSingleBinary(myFile)
+            //result shouldBe ("TODO")
+        }
+
+        // to test testEchoBodyFreeFormObjectResponseString
+        should("test testEchoBodyFreeFormObjectResponseString") {
+            // uncomment below to test testEchoBodyFreeFormObjectResponseString
+            //val body : kotlin.Any = Object // kotlin.Any | Free form object
+            //val result : kotlin.String = apiInstance.testEchoBodyFreeFormObjectResponseString(body)
+            //result shouldBe ("TODO")
+        }
+
+        // to test testEchoBodyPet
+        should("test testEchoBodyPet") {
+            // uncomment below to test testEchoBodyPet
+            //val apiPet : ApiPet =  // ApiPet | Pet object that needs to be added to the store
+            //val result : ApiPet = apiInstance.testEchoBodyPet(apiPet)
+            //result shouldBe ("TODO")
+        }
+
+        // to test testEchoBodyPetResponseString
+        should("test testEchoBodyPetResponseString") {
+            // uncomment below to test testEchoBodyPetResponseString
+            //val apiPet : ApiPet =  // ApiPet | Pet object that needs to be added to the store
+            //val result : kotlin.String = apiInstance.testEchoBodyPetResponseString(apiPet)
+            //result shouldBe ("TODO")
+        }
+
+        // to test testEchoBodyTagResponseString
+        should("test testEchoBodyTagResponseString") {
+            // uncomment below to test testEchoBodyTagResponseString
+            //val apiTag : ApiTag =  // ApiTag | Tag object
+            //val result : kotlin.String = apiInstance.testEchoBodyTagResponseString(apiTag)
+            //result shouldBe ("TODO")
+        }
+
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/apis/FormApiTest.kt

@@ -0,0 +1,52 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.apis
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.apis.FormApi
+
+class FormApiTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of FormApi
+        //val apiInstance = FormApi()
+
+        // to test testFormIntegerBooleanString
+        should("test testFormIntegerBooleanString") {
+            // uncomment below to test testFormIntegerBooleanString
+            //val integerForm : kotlin.Int = 56 // kotlin.Int | 
+            //val booleanForm : kotlin.Boolean = true // kotlin.Boolean | 
+            //val stringForm : kotlin.String = stringForm_example // kotlin.String | 
+            //val result : kotlin.String = apiInstance.testFormIntegerBooleanString(integerForm, booleanForm, stringForm)
+            //result shouldBe ("TODO")
+        }
+
+        // to test testFormOneof
+        should("test testFormOneof") {
+            // uncomment below to test testFormOneof
+            //val form1 : kotlin.String = form1_example // kotlin.String | 
+            //val form2 : kotlin.Int = 56 // kotlin.Int | 
+            //val form3 : kotlin.String = form3_example // kotlin.String | 
+            //val form4 : kotlin.Boolean = true // kotlin.Boolean | 
+            //val id : kotlin.Long = 789 // kotlin.Long | 
+            //val name : kotlin.String = name_example // kotlin.String | 
+            //val result : kotlin.String = apiInstance.testFormOneof(form1, form2, form3, form4, id, name)
+            //result shouldBe ("TODO")
+        }
+
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/apis/HeaderApiTest.kt

@@ -0,0 +1,42 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.apis
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.apis.HeaderApi
+import org.openapitools.client.models.ApiStringEnumRef
+
+class HeaderApiTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of HeaderApi
+        //val apiInstance = HeaderApi()
+
+        // to test testHeaderIntegerBooleanStringEnums
+        should("test testHeaderIntegerBooleanStringEnums") {
+            // uncomment below to test testHeaderIntegerBooleanStringEnums
+            //val integerHeader : kotlin.Int = 56 // kotlin.Int | 
+            //val booleanHeader : kotlin.Boolean = true // kotlin.Boolean | 
+            //val stringHeader : kotlin.String = stringHeader_example // kotlin.String | 
+            //val enumNonrefStringHeader : kotlin.String = enumNonrefStringHeader_example // kotlin.String | 
+            //val enumRefStringHeader : ApiStringEnumRef =  // ApiStringEnumRef | 
+            //val result : kotlin.String = apiInstance.testHeaderIntegerBooleanStringEnums(integerHeader, booleanHeader, stringHeader, enumNonrefStringHeader, enumRefStringHeader)
+            //result shouldBe ("TODO")
+        }
+
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/apis/PathApiTest.kt

@@ -0,0 +1,41 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.apis
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.apis.PathApi
+import org.openapitools.client.models.ApiStringEnumRef
+
+class PathApiTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of PathApi
+        //val apiInstance = PathApi()
+
+        // to test testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath
+        should("test testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath") {
+            // uncomment below to test testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath
+            //val pathString : kotlin.String = pathString_example // kotlin.String | 
+            //val pathInteger : kotlin.Int = 56 // kotlin.Int | 
+            //val enumNonrefStringPath : kotlin.String = enumNonrefStringPath_example // kotlin.String | 
+            //val enumRefStringPath : ApiStringEnumRef =  // ApiStringEnumRef | 
+            //val result : kotlin.String = apiInstance.testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath(pathString, pathInteger, enumNonrefStringPath, enumRefStringPath)
+            //result shouldBe ("TODO")
+        }
+
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/apis/QueryApiTest.kt

@@ -0,0 +1,85 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.apis
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.apis.QueryApi
+import org.openapitools.client.models.ApiPet
+import org.openapitools.client.models.ApiStringEnumRef
+import org.openapitools.client.models.ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter
+
+class QueryApiTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of QueryApi
+        //val apiInstance = QueryApi()
+
+        // to test testEnumRefString
+        should("test testEnumRefString") {
+            // uncomment below to test testEnumRefString
+            //val enumNonrefStringQuery : kotlin.String = enumNonrefStringQuery_example // kotlin.String | 
+            //val enumRefStringQuery : ApiStringEnumRef =  // ApiStringEnumRef | 
+            //val result : kotlin.String = apiInstance.testEnumRefString(enumNonrefStringQuery, enumRefStringQuery)
+            //result shouldBe ("TODO")
+        }
+
+        // to test testQueryDatetimeDateString
+        should("test testQueryDatetimeDateString") {
+            // uncomment below to test testQueryDatetimeDateString
+            //val datetimeQuery : java.time.OffsetDateTime = 2013-10-20T19:20:30+01:00 // java.time.OffsetDateTime | 
+            //val dateQuery : java.time.LocalDate = 2013-10-20 // java.time.LocalDate | 
+            //val stringQuery : kotlin.String = stringQuery_example // kotlin.String | 
+            //val result : kotlin.String = apiInstance.testQueryDatetimeDateString(datetimeQuery, dateQuery, stringQuery)
+            //result shouldBe ("TODO")
+        }
+
+        // to test testQueryIntegerBooleanString
+        should("test testQueryIntegerBooleanString") {
+            // uncomment below to test testQueryIntegerBooleanString
+            //val integerQuery : kotlin.Int = 56 // kotlin.Int | 
+            //val booleanQuery : kotlin.Boolean = true // kotlin.Boolean | 
+            //val stringQuery : kotlin.String = stringQuery_example // kotlin.String | 
+            //val result : kotlin.String = apiInstance.testQueryIntegerBooleanString(integerQuery, booleanQuery, stringQuery)
+            //result shouldBe ("TODO")
+        }
+
+        // to test testQueryStyleDeepObjectExplodeTrueObject
+        should("test testQueryStyleDeepObjectExplodeTrueObject") {
+            // uncomment below to test testQueryStyleDeepObjectExplodeTrueObject
+            //val queryObject : ApiPet =  // ApiPet | 
+            //val result : kotlin.String = apiInstance.testQueryStyleDeepObjectExplodeTrueObject(queryObject)
+            //result shouldBe ("TODO")
+        }
+
+        // to test testQueryStyleFormExplodeTrueArrayString
+        should("test testQueryStyleFormExplodeTrueArrayString") {
+            // uncomment below to test testQueryStyleFormExplodeTrueArrayString
+            //val queryObject : ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter =  // ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter | 
+            //val result : kotlin.String = apiInstance.testQueryStyleFormExplodeTrueArrayString(queryObject)
+            //result shouldBe ("TODO")
+        }
+
+        // to test testQueryStyleFormExplodeTrueObject
+        should("test testQueryStyleFormExplodeTrueObject") {
+            // uncomment below to test testQueryStyleFormExplodeTrueObject
+            //val queryObject : ApiPet =  // ApiPet | 
+            //val result : kotlin.String = apiInstance.testQueryStyleFormExplodeTrueObject(queryObject)
+            //result shouldBe ("TODO")
+        }
+
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/models/BirdTest.kt

@@ -0,0 +1,41 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.models.ApiBird
+
+class ApiBirdTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of ApiBird
+        //val modelInstance = ApiBird()
+
+        // to test the property `propertySize`
+        should("test propertySize") {
+            // uncomment below to test the property
+            //modelInstance.propertySize shouldBe ("TODO")
+        }
+
+        // to test the property `color`
+        should("test color") {
+            // uncomment below to test the property
+            //modelInstance.color shouldBe ("TODO")
+        }
+
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/models/CategoryTest.kt

@@ -0,0 +1,41 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.models.ApiCategory
+
+class ApiCategoryTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of ApiCategory
+        //val modelInstance = ApiCategory()
+
+        // to test the property `id`
+        should("test id") {
+            // uncomment below to test the property
+            //modelInstance.id shouldBe ("TODO")
+        }
+
+        // to test the property `name`
+        should("test name") {
+            // uncomment below to test the property
+            //modelInstance.name shouldBe ("TODO")
+        }
+
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/models/DefaultValueTest.kt

@@ -0,0 +1,78 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.models.ApiDefaultValue
+import org.openapitools.client.models.ApiStringEnumRef
+
+class ApiDefaultValueTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of ApiDefaultValue
+        //val modelInstance = ApiDefaultValue()
+
+        // to test the property `arrayStringEnumRefDefault`
+        should("test arrayStringEnumRefDefault") {
+            // uncomment below to test the property
+            //modelInstance.arrayStringEnumRefDefault shouldBe ("TODO")
+        }
+
+        // to test the property `arrayStringEnumDefault`
+        should("test arrayStringEnumDefault") {
+            // uncomment below to test the property
+            //modelInstance.arrayStringEnumDefault shouldBe ("TODO")
+        }
+
+        // to test the property `arrayStringDefault`
+        should("test arrayStringDefault") {
+            // uncomment below to test the property
+            //modelInstance.arrayStringDefault shouldBe ("TODO")
+        }
+
+        // to test the property `arrayIntegerDefault`
+        should("test arrayIntegerDefault") {
+            // uncomment below to test the property
+            //modelInstance.arrayIntegerDefault shouldBe ("TODO")
+        }
+
+        // to test the property `arrayString`
+        should("test arrayString") {
+            // uncomment below to test the property
+            //modelInstance.arrayString shouldBe ("TODO")
+        }
+
+        // to test the property `arrayStringNullable`
+        should("test arrayStringNullable") {
+            // uncomment below to test the property
+            //modelInstance.arrayStringNullable shouldBe ("TODO")
+        }
+
+        // to test the property `arrayStringExtensionNullable`
+        should("test arrayStringExtensionNullable") {
+            // uncomment below to test the property
+            //modelInstance.arrayStringExtensionNullable shouldBe ("TODO")
+        }
+
+        // to test the property `stringNullable`
+        should("test stringNullable") {
+            // uncomment below to test the property
+            //modelInstance.stringNullable shouldBe ("TODO")
+        }
+
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/models/NumberPropertiesOnlyTest.kt

@@ -0,0 +1,47 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.models.ApiNumberPropertiesOnly
+
+class ApiNumberPropertiesOnlyTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of ApiNumberPropertiesOnly
+        //val modelInstance = ApiNumberPropertiesOnly()
+
+        // to test the property `number`
+        should("test number") {
+            // uncomment below to test the property
+            //modelInstance.number shouldBe ("TODO")
+        }
+
+        // to test the property `float`
+        should("test float") {
+            // uncomment below to test the property
+            //modelInstance.float shouldBe ("TODO")
+        }
+
+        // to test the property `double`
+        should("test double") {
+            // uncomment below to test the property
+            //modelInstance.double shouldBe ("TODO")
+        }
+
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/models/PetTest.kt

@@ -0,0 +1,67 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.models.ApiPet
+import org.openapitools.client.models.ApiCategory
+import org.openapitools.client.models.ApiTag
+
+class ApiPetTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of ApiPet
+        //val modelInstance = ApiPet()
+
+        // to test the property `name`
+        should("test name") {
+            // uncomment below to test the property
+            //modelInstance.name shouldBe ("TODO")
+        }
+
+        // to test the property `photoUrls`
+        should("test photoUrls") {
+            // uncomment below to test the property
+            //modelInstance.photoUrls shouldBe ("TODO")
+        }
+
+        // to test the property `id`
+        should("test id") {
+            // uncomment below to test the property
+            //modelInstance.id shouldBe ("TODO")
+        }
+
+        // to test the property `category`
+        should("test category") {
+            // uncomment below to test the property
+            //modelInstance.category shouldBe ("TODO")
+        }
+
+        // to test the property `tags`
+        should("test tags") {
+            // uncomment below to test the property
+            //modelInstance.tags shouldBe ("TODO")
+        }
+
+        // to test the property `status` - pet status in the store
+        should("test status") {
+            // uncomment below to test the property
+            //modelInstance.status shouldBe ("TODO")
+        }
+
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/models/QueryTest.kt

@@ -0,0 +1,41 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.models.ApiQuery
+
+class ApiQueryTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of ApiQuery
+        //val modelInstance = ApiQuery()
+
+        // to test the property `id` - Query
+        should("test id") {
+            // uncomment below to test the property
+            //modelInstance.id shouldBe ("TODO")
+        }
+
+        // to test the property `outcomes`
+        should("test outcomes") {
+            // uncomment below to test the property
+            //modelInstance.outcomes shouldBe ("TODO")
+        }
+
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/models/StringEnumRefTest.kt

@@ -0,0 +1,29 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.models.ApiStringEnumRef
+
+class ApiStringEnumRefTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of ApiStringEnumRef
+        //val modelInstance = ApiStringEnumRef()
+
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/models/TagTest.kt

@@ -0,0 +1,41 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.models.ApiTag
+
+class ApiTagTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of ApiTag
+        //val modelInstance = ApiTag()
+
+        // to test the property `id`
+        should("test id") {
+            // uncomment below to test the property
+            //modelInstance.id shouldBe ("TODO")
+        }
+
+        // to test the property `name`
+        should("test name") {
+            // uncomment below to test the property
+            //modelInstance.name shouldBe ("TODO")
+        }
+
+    }
+}

samples/client/echo_api/kotlin-jvm-okhttp/src/test/kotlin/org/openapitools/client/models/TestQueryStyleFormExplodeTrueArrayStringQueryObjectParameterTest.kt

@@ -0,0 +1,35 @@
+/**
+ *
+ * Please note:
+ * This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * Do not edit this file manually.
+ *
+ */
+
+@file:Suppress(
+    "ArrayInDataClass",
+    "EnumEntryName",
+    "RemoveRedundantQualifierName",
+    "UnusedImport"
+)
+
+package org.openapitools.client.models
+
+import io.kotlintest.shouldBe
+import io.kotlintest.specs.ShouldSpec
+
+import org.openapitools.client.models.ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter
+
+class ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameterTest : ShouldSpec() {
+    init {
+        // uncomment below to create an instance of ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter
+        //val modelInstance = ApiTestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter()
+
+        // to test the property `propertyValues`
+        should("test propertyValues") {
+            // uncomment below to test the property
+            //modelInstance.propertyValues shouldBe ("TODO")
+        }
+
+    }
+}