[kotlin-client][jvm-spring-*] Fix runtime error in endpoints of type Unit (#17664)

* Fixed invalid extraction of response body in kotlin-client jvm-spring-* * Generated echo-api for kotlin-jvm-spring-3-restclient * Specific echo-api for Kotlin without allOf/anyOf * Specific echo-api for Kotlin without allOf/anyOf * Generated all samples * Added kotlin-jvm-spring-3-restclient sample to workflow * Fixed syntax problem
2025-12-03 00:43:46 +00:00 · 2024-01-22 03:57:40 +01:00
parent 189bf7d6c5
commit 227c8602f7
62 changed files with 4290 additions and 61 deletions
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/apis/AuthApi.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/apis/AuthApi.kt
@@ -0,0 +1,108 @@
+/**
+ *
+ * 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 com.fasterxml.jackson.annotation.JsonProperty
+
+import org.springframework.web.client.RestClient
+import org.springframework.web.client.RestClientResponseException
+
+import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter
+import org.springframework.http.ResponseEntity
+import org.springframework.http.MediaType
+
+
+import org.openapitools.client.infrastructure.*
+
+class AuthApi(client: RestClient) : ApiClient(client) {
+
+    constructor(baseUrl: String) : this(RestClient.builder()
+        .baseUrl(baseUrl)
+        .messageConverters { it.add(MappingJackson2HttpMessageConverter()) }
+        .build()
+    )
+
+
+    @Throws(RestClientResponseException::class)
+    fun testAuthHttpBasic(): kotlin.String {
+        val result = testAuthHttpBasicWithHttpInfo()
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testAuthHttpBasicWithHttpInfo(): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testAuthHttpBasicRequestConfig()
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testAuthHttpBasicRequestConfig() : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Accept"] = "text/plain"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/auth/http/basic",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = true,
+            body = localVariableBody
+        )
+    }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testAuthHttpBearer(): kotlin.String {
+        val result = testAuthHttpBearerWithHttpInfo()
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testAuthHttpBearerWithHttpInfo(): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testAuthHttpBearerRequestConfig()
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testAuthHttpBearerRequestConfig() : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Accept"] = "text/plain"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/auth/http/bearer",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = true,
+            body = localVariableBody
+        )
+    }
+
+}
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/apis/BodyApi.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/apis/BodyApi.kt
@@ -0,0 +1,327 @@
+/**
+ *
+ * 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 com.fasterxml.jackson.annotation.JsonProperty
+
+import org.springframework.web.client.RestClient
+import org.springframework.web.client.RestClientResponseException
+
+import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter
+import org.springframework.http.ResponseEntity
+import org.springframework.http.MediaType
+
+
+import org.openapitools.client.models.Pet
+import org.openapitools.client.models.Tag
+import org.openapitools.client.infrastructure.*
+
+class BodyApi(client: RestClient) : ApiClient(client) {
+
+    constructor(baseUrl: String) : this(RestClient.builder()
+        .baseUrl(baseUrl)
+        .messageConverters { it.add(MappingJackson2HttpMessageConverter()) }
+        .build()
+    )
+
+
+    @Throws(RestClientResponseException::class)
+    fun testBinaryGif(): java.io.File {
+        val result = testBinaryGifWithHttpInfo()
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testBinaryGifWithHttpInfo(): ResponseEntity<java.io.File> {
+        val localVariableConfig = testBinaryGifRequestConfig()
+        return request<Unit, java.io.File>(
+            localVariableConfig
+        )
+    }
+
+    fun testBinaryGifRequestConfig() : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Accept"] = "image/gif"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/binary/gif",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testBodyApplicationOctetstreamBinary(body: java.io.File? = null): kotlin.String {
+        val result = testBodyApplicationOctetstreamBinaryWithHttpInfo(body = body)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testBodyApplicationOctetstreamBinaryWithHttpInfo(body: java.io.File? = null): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testBodyApplicationOctetstreamBinaryRequestConfig(body = body)
+        return request<java.io.File, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testBodyApplicationOctetstreamBinaryRequestConfig(body: java.io.File? = null) : RequestConfig<java.io.File> {
+        val localVariableBody = body
+        val localVariableQuery = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Content-Type"] = "application/octet-stream"
+        localVariableHeaders["Accept"] = "text/plain"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/body/application/octetstream/binary",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testBodyMultipartFormdataArrayOfBinary(files: kotlin.collections.List<java.io.File>): kotlin.String {
+        val result = testBodyMultipartFormdataArrayOfBinaryWithHttpInfo(files = files)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testBodyMultipartFormdataArrayOfBinaryWithHttpInfo(files: kotlin.collections.List<java.io.File>): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testBodyMultipartFormdataArrayOfBinaryRequestConfig(files = files)
+        return request<Map<String, PartConfig<*>>, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    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 = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf("Content-Type" to "multipart/form-data")
+        localVariableHeaders["Accept"] = "text/plain"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/body/application/octetstream/array_of_binary",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testBodyMultipartFormdataSingleBinary(myFile: java.io.File? = null): kotlin.String {
+        val result = testBodyMultipartFormdataSingleBinaryWithHttpInfo(myFile = myFile)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testBodyMultipartFormdataSingleBinaryWithHttpInfo(myFile: java.io.File? = null): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testBodyMultipartFormdataSingleBinaryRequestConfig(myFile = myFile)
+        return request<Map<String, PartConfig<*>>, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testBodyMultipartFormdataSingleBinaryRequestConfig(myFile: java.io.File? = null) : RequestConfig<Map<String, PartConfig<*>>> {
+        val localVariableBody = mapOf(
+            "my-file" to PartConfig(body = myFile, headers = mutableMapOf()),)
+        val localVariableQuery = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf("Content-Type" to "multipart/form-data")
+        localVariableHeaders["Accept"] = "text/plain"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/body/application/octetstream/single_binary",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testEchoBodyFreeFormObjectResponseString(body: kotlin.Any? = null): kotlin.String {
+        val result = testEchoBodyFreeFormObjectResponseStringWithHttpInfo(body = body)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testEchoBodyFreeFormObjectResponseStringWithHttpInfo(body: kotlin.Any? = null): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testEchoBodyFreeFormObjectResponseStringRequestConfig(body = body)
+        return request<kotlin.Any, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testEchoBodyFreeFormObjectResponseStringRequestConfig(body: kotlin.Any? = null) : RequestConfig<kotlin.Any> {
+        val localVariableBody = body
+        val localVariableQuery = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Content-Type"] = "application/json"
+        localVariableHeaders["Accept"] = "text/plain"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/echo/body/FreeFormObject/response_string",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testEchoBodyPet(pet: Pet? = null): Pet {
+        val result = testEchoBodyPetWithHttpInfo(pet = pet)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testEchoBodyPetWithHttpInfo(pet: Pet? = null): ResponseEntity<Pet> {
+        val localVariableConfig = testEchoBodyPetRequestConfig(pet = pet)
+        return request<Pet, Pet>(
+            localVariableConfig
+        )
+    }
+
+    fun testEchoBodyPetRequestConfig(pet: Pet? = null) : RequestConfig<Pet> {
+        val localVariableBody = pet
+        val localVariableQuery = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Content-Type"] = "application/json"
+        localVariableHeaders["Accept"] = "application/json"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/echo/body/Pet",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testEchoBodyPetResponseString(pet: Pet? = null): kotlin.String {
+        val result = testEchoBodyPetResponseStringWithHttpInfo(pet = pet)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testEchoBodyPetResponseStringWithHttpInfo(pet: Pet? = null): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testEchoBodyPetResponseStringRequestConfig(pet = pet)
+        return request<Pet, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testEchoBodyPetResponseStringRequestConfig(pet: Pet? = null) : RequestConfig<Pet> {
+        val localVariableBody = pet
+        val localVariableQuery = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Content-Type"] = "application/json"
+        localVariableHeaders["Accept"] = "text/plain"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/echo/body/Pet/response_string",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testEchoBodyTagResponseString(tag: Tag? = null): kotlin.String {
+        val result = testEchoBodyTagResponseStringWithHttpInfo(tag = tag)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testEchoBodyTagResponseStringWithHttpInfo(tag: Tag? = null): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testEchoBodyTagResponseStringRequestConfig(tag = tag)
+        return request<Tag, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testEchoBodyTagResponseStringRequestConfig(tag: Tag? = null) : RequestConfig<Tag> {
+        val localVariableBody = tag
+        val localVariableQuery = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Content-Type"] = "application/json"
+        localVariableHeaders["Accept"] = "text/plain"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/echo/body/Tag/response_string",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+}
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/apis/FormApi.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/apis/FormApi.kt
@@ -0,0 +1,117 @@
+/**
+ *
+ * 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 com.fasterxml.jackson.annotation.JsonProperty
+
+import org.springframework.web.client.RestClient
+import org.springframework.web.client.RestClientResponseException
+
+import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter
+import org.springframework.http.ResponseEntity
+import org.springframework.http.MediaType
+
+
+import org.openapitools.client.infrastructure.*
+
+class FormApi(client: RestClient) : ApiClient(client) {
+
+    constructor(baseUrl: String) : this(RestClient.builder()
+        .baseUrl(baseUrl)
+        .messageConverters { it.add(MappingJackson2HttpMessageConverter()) }
+        .build()
+    )
+
+
+    @Throws(RestClientResponseException::class)
+    fun testFormIntegerBooleanString(integerForm: kotlin.Int? = null, booleanForm: kotlin.Boolean? = null, stringForm: kotlin.String? = null): kotlin.String {
+        val result = testFormIntegerBooleanStringWithHttpInfo(integerForm = integerForm, booleanForm = booleanForm, stringForm = stringForm)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testFormIntegerBooleanStringWithHttpInfo(integerForm: kotlin.Int? = null, booleanForm: kotlin.Boolean? = null, stringForm: kotlin.String? = null): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testFormIntegerBooleanStringRequestConfig(integerForm = integerForm, booleanForm = booleanForm, stringForm = stringForm)
+        return request<Map<String, PartConfig<*>>, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testFormIntegerBooleanStringRequestConfig(integerForm: kotlin.Int? = null, booleanForm: kotlin.Boolean? = null, stringForm: kotlin.String? = null) : 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 = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf("Content-Type" to "application/x-www-form-urlencoded")
+        localVariableHeaders["Accept"] = "text/plain"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/form/integer/boolean/string",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    @Throws(RestClientResponseException::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 result = testFormOneofWithHttpInfo(form1 = form1, form2 = form2, form3 = form3, form4 = form4, id = id, name = name)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testFormOneofWithHttpInfo(form1: kotlin.String? = null, form2: kotlin.Int? = null, form3: kotlin.String? = null, form4: kotlin.Boolean? = null, id: kotlin.Long? = null, name: kotlin.String? = null): ResponseEntity<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
+        )
+    }
+
+    fun testFormOneofRequestConfig(form1: kotlin.String? = null, form2: kotlin.Int? = null, form3: kotlin.String? = null, form4: kotlin.Boolean? = null, id: kotlin.Long? = null, name: kotlin.String? = null) : 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 = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf("Content-Type" to "application/x-www-form-urlencoded")
+        localVariableHeaders["Accept"] = "text/plain"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.POST,
+            path = "/form/oneof",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+}
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/apis/HeaderApi.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/apis/HeaderApi.kt
@@ -0,0 +1,88 @@
+/**
+ *
+ * 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 com.fasterxml.jackson.annotation.JsonProperty
+
+import org.springframework.web.client.RestClient
+import org.springframework.web.client.RestClientResponseException
+
+import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter
+import org.springframework.http.ResponseEntity
+import org.springframework.http.MediaType
+
+
+import org.openapitools.client.models.StringEnumRef
+import org.openapitools.client.infrastructure.*
+
+class HeaderApi(client: RestClient) : ApiClient(client) {
+
+    constructor(baseUrl: String) : this(RestClient.builder()
+        .baseUrl(baseUrl)
+        .messageConverters { it.add(MappingJackson2HttpMessageConverter()) }
+        .build()
+    )
+
+    /**
+     * enum for parameter enumNonrefStringHeader
+     */
+     enum class EnumNonrefStringHeaderTestHeaderIntegerBooleanStringEnums(val value: kotlin.String) {
+         @JsonProperty(value = "success") success("success"),
+         @JsonProperty(value = "failure") failure("failure"),
+         @JsonProperty(value = "unclassified") unclassified("unclassified"),
+     }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testHeaderIntegerBooleanStringEnums(integerHeader: kotlin.Int? = null, booleanHeader: kotlin.Boolean? = null, stringHeader: kotlin.String? = null, enumNonrefStringHeader: EnumNonrefStringHeaderTestHeaderIntegerBooleanStringEnums? = null, enumRefStringHeader: StringEnumRef? = null): kotlin.String {
+        val result = testHeaderIntegerBooleanStringEnumsWithHttpInfo(integerHeader = integerHeader, booleanHeader = booleanHeader, stringHeader = stringHeader, enumNonrefStringHeader = enumNonrefStringHeader, enumRefStringHeader = enumRefStringHeader)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testHeaderIntegerBooleanStringEnumsWithHttpInfo(integerHeader: kotlin.Int? = null, booleanHeader: kotlin.Boolean? = null, stringHeader: kotlin.String? = null, enumNonrefStringHeader: EnumNonrefStringHeaderTestHeaderIntegerBooleanStringEnums? = null, enumRefStringHeader: StringEnumRef? = null): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testHeaderIntegerBooleanStringEnumsRequestConfig(integerHeader = integerHeader, booleanHeader = booleanHeader, stringHeader = stringHeader, enumNonrefStringHeader = enumNonrefStringHeader, enumRefStringHeader = enumRefStringHeader)
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testHeaderIntegerBooleanStringEnumsRequestConfig(integerHeader: kotlin.Int? = null, booleanHeader: kotlin.Boolean? = null, stringHeader: kotlin.String? = null, enumNonrefStringHeader: EnumNonrefStringHeaderTestHeaderIntegerBooleanStringEnums? = null, enumRefStringHeader: StringEnumRef? = null) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+        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"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/header/integer/boolean/string/enums",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+}
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/apis/PathApi.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/apis/PathApi.kt
@@ -0,0 +1,87 @@
+/**
+ *
+ * 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 com.fasterxml.jackson.annotation.JsonProperty
+
+import org.springframework.web.client.RestClient
+import org.springframework.web.client.RestClientResponseException
+
+import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter
+import org.springframework.http.ResponseEntity
+import org.springframework.http.MediaType
+
+
+import org.openapitools.client.models.StringEnumRef
+import org.openapitools.client.infrastructure.*
+
+class PathApi(client: RestClient) : ApiClient(client) {
+
+    constructor(baseUrl: String) : this(RestClient.builder()
+        .baseUrl(baseUrl)
+        .messageConverters { it.add(MappingJackson2HttpMessageConverter()) }
+        .build()
+    )
+
+    /**
+     * enum for parameter enumNonrefStringPath
+     */
+     enum class EnumNonrefStringPathTestsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath(val value: kotlin.String) {
+         @JsonProperty(value = "success") success("success"),
+         @JsonProperty(value = "failure") failure("failure"),
+         @JsonProperty(value = "unclassified") unclassified("unclassified"),
+     }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath(pathString: kotlin.String, pathInteger: kotlin.Int, enumNonrefStringPath: EnumNonrefStringPathTestsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath, enumRefStringPath: StringEnumRef): kotlin.String {
+        val result = testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPathWithHttpInfo(pathString = pathString, pathInteger = pathInteger, enumNonrefStringPath = enumNonrefStringPath, enumRefStringPath = enumRefStringPath)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPathWithHttpInfo(pathString: kotlin.String, pathInteger: kotlin.Int, enumNonrefStringPath: EnumNonrefStringPathTestsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath, enumRefStringPath: StringEnumRef): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPathRequestConfig(pathString = pathString, pathInteger = pathInteger, enumNonrefStringPath = enumNonrefStringPath, enumRefStringPath = enumRefStringPath)
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPathRequestConfig(pathString: kotlin.String, pathInteger: kotlin.Int, enumNonrefStringPath: EnumNonrefStringPathTestsPathStringPathStringIntegerPathIntegerEnumNonrefStringPathEnumRefStringPath, enumRefStringPath: StringEnumRef) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Accept"] = "text/plain"
+
+        val params = mutableMapOf<String, Any>(
+            "path_string" to pathString,
+            "path_integer" to pathInteger,
+            "enum_nonref_string_path" to enumNonrefStringPath.value,
+            "enum_ref_string_path" to enumRefStringPath,
+        )
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/path/string/{path_string}/integer/{path_integer}/{enum_nonref_string_path}/{enum_ref_string_path}",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+}
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/apis/QueryApi.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/apis/QueryApi.kt
@@ -0,0 +1,305 @@
+/**
+ *
+ * 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 com.fasterxml.jackson.annotation.JsonProperty
+
+import org.springframework.web.client.RestClient
+import org.springframework.web.client.RestClientResponseException
+
+import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter
+import org.springframework.http.ResponseEntity
+import org.springframework.http.MediaType
+
+
+import org.openapitools.client.models.Pet
+import org.openapitools.client.models.StringEnumRef
+import org.openapitools.client.models.TestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter
+import org.openapitools.client.infrastructure.*
+
+class QueryApi(client: RestClient) : ApiClient(client) {
+
+    constructor(baseUrl: String) : this(RestClient.builder()
+        .baseUrl(baseUrl)
+        .messageConverters { it.add(MappingJackson2HttpMessageConverter()) }
+        .build()
+    )
+
+    /**
+     * enum for parameter enumNonrefStringQuery
+     */
+     enum class EnumNonrefStringQueryTestEnumRefString(val value: kotlin.String) {
+         @JsonProperty(value = "success") success("success"),
+         @JsonProperty(value = "failure") failure("failure"),
+         @JsonProperty(value = "unclassified") unclassified("unclassified"),
+     }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testEnumRefString(enumNonrefStringQuery: EnumNonrefStringQueryTestEnumRefString? = null, enumRefStringQuery: StringEnumRef? = null): kotlin.String {
+        val result = testEnumRefStringWithHttpInfo(enumNonrefStringQuery = enumNonrefStringQuery, enumRefStringQuery = enumRefStringQuery)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testEnumRefStringWithHttpInfo(enumNonrefStringQuery: EnumNonrefStringQueryTestEnumRefString? = null, enumRefStringQuery: StringEnumRef? = null): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testEnumRefStringRequestConfig(enumNonrefStringQuery = enumNonrefStringQuery, enumRefStringQuery = enumRefStringQuery)
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testEnumRefStringRequestConfig(enumNonrefStringQuery: EnumNonrefStringQueryTestEnumRefString? = null, enumRefStringQuery: StringEnumRef? = null) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery = mutableMapOf<kotlin.String, kotlin.collections.List<kotlin.String>>()
+            .apply {
+                if (enumNonrefStringQuery != null) {
+                    put("enum_nonref_string_query", listOf(enumNonrefStringQuery.toString()))
+                }
+                if (enumRefStringQuery != null) {
+                    put("enum_ref_string_query", listOf(enumRefStringQuery.toString()))
+                }
+            }
+        val localVariableHeaders: MutableMap<String, String> = mutableMapOf()
+        localVariableHeaders["Accept"] = "text/plain"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/query/enum_ref_string",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testQueryDatetimeDateString(datetimeQuery: java.time.OffsetDateTime? = null, dateQuery: java.time.LocalDate? = null, stringQuery: kotlin.String? = null): kotlin.String {
+        val result = testQueryDatetimeDateStringWithHttpInfo(datetimeQuery = datetimeQuery, dateQuery = dateQuery, stringQuery = stringQuery)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testQueryDatetimeDateStringWithHttpInfo(datetimeQuery: java.time.OffsetDateTime? = null, dateQuery: java.time.LocalDate? = null, stringQuery: kotlin.String? = null): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testQueryDatetimeDateStringRequestConfig(datetimeQuery = datetimeQuery, dateQuery = dateQuery, stringQuery = stringQuery)
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testQueryDatetimeDateStringRequestConfig(datetimeQuery: java.time.OffsetDateTime? = null, dateQuery: java.time.LocalDate? = null, stringQuery: kotlin.String? = null) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery = 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"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/query/datetime/date/string",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testQueryIntegerBooleanString(integerQuery: kotlin.Int? = null, booleanQuery: kotlin.Boolean? = null, stringQuery: kotlin.String? = null): kotlin.String {
+        val result = testQueryIntegerBooleanStringWithHttpInfo(integerQuery = integerQuery, booleanQuery = booleanQuery, stringQuery = stringQuery)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testQueryIntegerBooleanStringWithHttpInfo(integerQuery: kotlin.Int? = null, booleanQuery: kotlin.Boolean? = null, stringQuery: kotlin.String? = null): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testQueryIntegerBooleanStringRequestConfig(integerQuery = integerQuery, booleanQuery = booleanQuery, stringQuery = stringQuery)
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testQueryIntegerBooleanStringRequestConfig(integerQuery: kotlin.Int? = null, booleanQuery: kotlin.Boolean? = null, stringQuery: kotlin.String? = null) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery = 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"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/query/integer/boolean/string",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testQueryStyleDeepObjectExplodeTrueObject(queryObject: Pet? = null): kotlin.String {
+        val result = testQueryStyleDeepObjectExplodeTrueObjectWithHttpInfo(queryObject = queryObject)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testQueryStyleDeepObjectExplodeTrueObjectWithHttpInfo(queryObject: Pet? = null): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testQueryStyleDeepObjectExplodeTrueObjectRequestConfig(queryObject = queryObject)
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testQueryStyleDeepObjectExplodeTrueObjectRequestConfig(queryObject: Pet? = null) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery = 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"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/query/style_deepObject/explode_true/object",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testQueryStyleFormExplodeTrueArrayString(queryObject: TestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter? = null): kotlin.String {
+        val result = testQueryStyleFormExplodeTrueArrayStringWithHttpInfo(queryObject = queryObject)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testQueryStyleFormExplodeTrueArrayStringWithHttpInfo(queryObject: TestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter? = null): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testQueryStyleFormExplodeTrueArrayStringRequestConfig(queryObject = queryObject)
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testQueryStyleFormExplodeTrueArrayStringRequestConfig(queryObject: TestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter? = null) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery = 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"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/query/style_form/explode_true/array_string",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+
+    @Throws(RestClientResponseException::class)
+    fun testQueryStyleFormExplodeTrueObject(queryObject: Pet? = null): kotlin.String {
+        val result = testQueryStyleFormExplodeTrueObjectWithHttpInfo(queryObject = queryObject)
+        return result.body!!
+    }
+
+    @Throws(RestClientResponseException::class)
+    fun testQueryStyleFormExplodeTrueObjectWithHttpInfo(queryObject: Pet? = null): ResponseEntity<kotlin.String> {
+        val localVariableConfig = testQueryStyleFormExplodeTrueObjectRequestConfig(queryObject = queryObject)
+        return request<Unit, kotlin.String>(
+            localVariableConfig
+        )
+    }
+
+    fun testQueryStyleFormExplodeTrueObjectRequestConfig(queryObject: Pet? = null) : RequestConfig<Unit> {
+        val localVariableBody = null
+        val localVariableQuery = 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"
+
+        val params = mutableMapOf<String, Any>(
+        )
+
+        return RequestConfig(
+            method = RequestMethod.GET,
+            path = "/query/style_form/explode_true/object",
+            params = params,
+            query = localVariableQuery,
+            headers = localVariableHeaders,
+            requiresAuthentication = false,
+            body = localVariableBody
+        )
+    }
+
+}
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/infrastructure/ApiAbstractions.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/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) = 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)
+        = 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))
+    }
+}
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
@@ -0,0 +1,61 @@
+package org.openapitools.client.infrastructure;
+
+import org.springframework.core.ParameterizedTypeReference
+import org.springframework.http.HttpHeaders
+import org.springframework.http.HttpMethod
+import org.springframework.http.MediaType
+import org.springframework.web.client.RestClient
+import org.springframework.http.ResponseEntity
+import org.springframework.util.LinkedMultiValueMap
+
+open class ApiClient(protected val client: RestClient) {
+
+    protected inline fun <reified I : Any, reified T: Any?> request(requestConfig: RequestConfig<I>): ResponseEntity<T> {
+        return prepare(defaults(requestConfig))
+            .retrieve()
+            .toEntity(object : ParameterizedTypeReference<T>() {})
+    }
+
+    protected fun <I : Any> prepare(requestConfig: RequestConfig<I>) =
+        client.method(requestConfig)
+            .uri(requestConfig)
+            .headers(requestConfig)
+            .nullableBody(requestConfig)
+
+    protected fun <I> defaults(requestConfig: RequestConfig<I>) =
+        requestConfig.apply {
+            if (body != null && headers[HttpHeaders.CONTENT_TYPE].isNullOrEmpty()) {
+                headers[HttpHeaders.CONTENT_TYPE] = MediaType.APPLICATION_JSON_VALUE
+            }
+            if (headers[HttpHeaders.ACCEPT].isNullOrEmpty()) {
+                headers[HttpHeaders.ACCEPT] = MediaType.APPLICATION_JSON_VALUE
+            }
+        }
+
+    private fun <I> RestClient.method(requestConfig: RequestConfig<I>)=
+        method(HttpMethod.valueOf(requestConfig.method.name))
+
+    private fun <I> RestClient.RequestBodyUriSpec.uri(requestConfig: RequestConfig<I>) =
+        uri { builder ->
+            builder
+                .path(requestConfig.path)
+                .queryParams(LinkedMultiValueMap(requestConfig.query))
+                .build(requestConfig.params)
+        }
+
+    private fun <I> RestClient.RequestBodySpec.headers(requestConfig: RequestConfig<I>) =
+        apply { requestConfig.headers.forEach { (name, value) -> header(name, value) } }
+
+    private fun <I : Any> RestClient.RequestBodySpec.nullableBody(requestConfig: RequestConfig<I>) =
+        apply { if (requestConfig.body != null) body(requestConfig.body) }
+}
+
+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.jacksonObjectMapper.writeValueAsString(value).replace("\"", "")
+    }
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/infrastructure/PartConfig.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/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
+)
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/infrastructure/RequestConfig.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/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
+)
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/infrastructure/RequestMethod.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/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
+}
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/infrastructure/Serializer.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/infrastructure/Serializer.kt
@@ -0,0 +1,16 @@
+package org.openapitools.client.infrastructure
+
+import com.fasterxml.jackson.databind.DeserializationFeature
+import com.fasterxml.jackson.databind.ObjectMapper
+import com.fasterxml.jackson.databind.SerializationFeature
+import com.fasterxml.jackson.annotation.JsonInclude
+import com.fasterxml.jackson.module.kotlin.jacksonObjectMapper
+
+object Serializer {
+    @JvmStatic
+    val jacksonObjectMapper: ObjectMapper = jacksonObjectMapper()
+        .findAndRegisterModules()
+        .setSerializationInclusion(JsonInclude.Include.NON_ABSENT)
+        .configure(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_USING_DEFAULT_VALUE, true)
+        .configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false)
+}
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/Bird.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/Bird.kt
@@ -0,0 +1,39 @@
+/**
+ *
+ * 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.fasterxml.jackson.annotation.JsonEnumDefaultValue
+import com.fasterxml.jackson.annotation.JsonProperty
+
+/**
+ * 
+ *
+ * @param propertySize 
+ * @param color 
+ */
+
+
+data class Bird (
+
+    @field:JsonProperty("size")
+    val propertySize: kotlin.String? = null,
+
+    @field:JsonProperty("color")
+    val color: kotlin.String? = null
+
+)
+
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/Category.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/Category.kt
@@ -0,0 +1,39 @@
+/**
+ *
+ * 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.fasterxml.jackson.annotation.JsonEnumDefaultValue
+import com.fasterxml.jackson.annotation.JsonProperty
+
+/**
+ * 
+ *
+ * @param id 
+ * @param name 
+ */
+
+
+data class Category (
+
+    @field:JsonProperty("id")
+    val id: kotlin.Long? = null,
+
+    @field:JsonProperty("name")
+    val name: kotlin.String? = null
+
+)
+
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/DefaultValue.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/DefaultValue.kt
@@ -0,0 +1,77 @@
+/**
+ *
+ * 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.StringEnumRef
+
+import com.fasterxml.jackson.annotation.JsonEnumDefaultValue
+import com.fasterxml.jackson.annotation.JsonProperty
+
+/**
+ * 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 DefaultValue (
+
+    @field:JsonProperty("array_string_enum_ref_default")
+    val arrayStringEnumRefDefault: kotlin.collections.List<StringEnumRef>? = null,
+
+    @field:JsonProperty("array_string_enum_default")
+    val arrayStringEnumDefault: kotlin.collections.List<DefaultValue.ArrayStringEnumDefault>? = null,
+
+    @field:JsonProperty("array_string_default")
+    val arrayStringDefault: kotlin.collections.List<kotlin.String>? = arrayListOf("failure","skipped"),
+
+    @field:JsonProperty("array_integer_default")
+    val arrayIntegerDefault: kotlin.collections.List<kotlin.Int>? = arrayListOf(1,3),
+
+    @field:JsonProperty("array_string")
+    val arrayString: kotlin.collections.List<kotlin.String>? = null,
+
+    @field:JsonProperty("array_string_nullable")
+    val arrayStringNullable: kotlin.collections.List<kotlin.String>? = null,
+
+    @field:JsonProperty("array_string_extension_nullable")
+    val arrayStringExtensionNullable: kotlin.collections.List<kotlin.String>? = null,
+
+    @field:JsonProperty("string_nullable")
+    val stringNullable: kotlin.String? = null
+
+) {
+
+    /**
+     * 
+     *
+     * Values: success,failure,unclassified,unknownDefaultOpenApi
+     */
+    enum class ArrayStringEnumDefault(val value: kotlin.String) {
+        @JsonProperty(value = "success") success("success"),
+        @JsonProperty(value = "failure") failure("failure"),
+        @JsonProperty(value = "unclassified") unclassified("unclassified"),
+        @JsonProperty(value = "unknown_default_open_api") @JsonEnumDefaultValue unknownDefaultOpenApi("unknown_default_open_api");
+    }
+}
+
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/NumberPropertiesOnly.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/NumberPropertiesOnly.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.models
+
+
+import com.fasterxml.jackson.annotation.JsonEnumDefaultValue
+import com.fasterxml.jackson.annotation.JsonProperty
+
+/**
+ * 
+ *
+ * @param number 
+ * @param float 
+ * @param double 
+ */
+
+
+data class NumberPropertiesOnly (
+
+    @field:JsonProperty("number")
+    val number: java.math.BigDecimal? = null,
+
+    @field:JsonProperty("float")
+    val float: kotlin.Float? = null,
+
+    @field:JsonProperty("double")
+    val double: kotlin.Double? = null
+
+)
+
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/Pet.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/Pet.kt
@@ -0,0 +1,71 @@
+/**
+ *
+ * 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.Category
+import org.openapitools.client.models.Tag
+
+import com.fasterxml.jackson.annotation.JsonEnumDefaultValue
+import com.fasterxml.jackson.annotation.JsonProperty
+
+/**
+ * 
+ *
+ * @param name 
+ * @param photoUrls 
+ * @param id 
+ * @param category 
+ * @param tags 
+ * @param status pet status in the store
+ */
+
+
+data class Pet (
+
+    @field:JsonProperty("name")
+    val name: kotlin.String,
+
+    @field:JsonProperty("photoUrls")
+    val photoUrls: kotlin.collections.List<kotlin.String>,
+
+    @field:JsonProperty("id")
+    val id: kotlin.Long? = null,
+
+    @field:JsonProperty("category")
+    val category: Category? = null,
+
+    @field:JsonProperty("tags")
+    val tags: kotlin.collections.List<Tag>? = null,
+
+    /* pet status in the store */
+    @field:JsonProperty("status")
+    val status: Pet.Status? = null
+
+) {
+
+    /**
+     * pet status in the store
+     *
+     * Values: available,pending,sold,unknownDefaultOpenApi
+     */
+    enum class Status(val value: kotlin.String) {
+        @JsonProperty(value = "available") available("available"),
+        @JsonProperty(value = "pending") pending("pending"),
+        @JsonProperty(value = "sold") sold("sold"),
+        @JsonProperty(value = "unknown_default_open_api") @JsonEnumDefaultValue unknownDefaultOpenApi("unknown_default_open_api");
+    }
+}
+
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/Query.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/Query.kt
@@ -0,0 +1,53 @@
+/**
+ *
+ * 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.fasterxml.jackson.annotation.JsonEnumDefaultValue
+import com.fasterxml.jackson.annotation.JsonProperty
+
+/**
+ * 
+ *
+ * @param id Query
+ * @param outcomes 
+ */
+
+
+data class Query (
+
+    /* Query */
+    @field:JsonProperty("id")
+    val id: kotlin.Long? = null,
+
+    @field:JsonProperty("outcomes")
+    val outcomes: kotlin.collections.List<Query.Outcomes>? = null
+
+) {
+
+    /**
+     * 
+     *
+     * Values: sUCCESS,fAILURE,sKIPPED,unknownDefaultOpenApi
+     */
+    enum class Outcomes(val value: kotlin.String) {
+        @JsonProperty(value = "SUCCESS") sUCCESS("SUCCESS"),
+        @JsonProperty(value = "FAILURE") fAILURE("FAILURE"),
+        @JsonProperty(value = "SKIPPED") sKIPPED("SKIPPED"),
+        @JsonProperty(value = "unknown_default_open_api") @JsonEnumDefaultValue unknownDefaultOpenApi("unknown_default_open_api");
+    }
+}
+
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/StringEnumRef.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/StringEnumRef.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 com.fasterxml.jackson.annotation.JsonProperty
+
+/**
+ * 
+ *
+ * Values: success,failure,unclassified,unknownDefaultOpenApi
+ */
+
+enum class StringEnumRef(val value: kotlin.String) {
+
+    @JsonProperty(value = "success")
+    success("success"),
+
+    @JsonProperty(value = "failure")
+    failure("failure"),
+
+    @JsonProperty(value = "unclassified")
+    unclassified("unclassified"),
+
+    @JsonProperty(value = "unknown_default_open_api")
+    unknownDefaultOpenApi("unknown_default_open_api");
+
+    /**
+     * 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 StringEnumRef) "$data" else null
+
+        /**
+         * Returns a valid [StringEnumRef] for [data], null otherwise.
+         */
+        fun decode(data: kotlin.Any?): StringEnumRef? = data?.let {
+          val normalizedData = "$it".lowercase()
+          values().firstOrNull { value ->
+            it == value || normalizedData == "$value".lowercase()
+          }
+        }
+    }
+}
+
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/Tag.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/Tag.kt
@@ -0,0 +1,39 @@
+/**
+ *
+ * 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.fasterxml.jackson.annotation.JsonEnumDefaultValue
+import com.fasterxml.jackson.annotation.JsonProperty
+
+/**
+ * 
+ *
+ * @param id 
+ * @param name 
+ */
+
+
+data class Tag (
+
+    @field:JsonProperty("id")
+    val id: kotlin.Long? = null,
+
+    @field:JsonProperty("name")
+    val name: kotlin.String? = null
+
+)
+
--- a/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/TestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter.kt
+++ b/samples/client/echo_api/kotlin-jvm-spring-3-restclient/src/main/kotlin/org/openapitools/client/models/TestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter.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 com.fasterxml.jackson.annotation.JsonEnumDefaultValue
+import com.fasterxml.jackson.annotation.JsonProperty
+
+/**
+ * 
+ *
+ * @param propertyValues 
+ */
+
+
+data class TestQueryStyleFormExplodeTrueArrayStringQueryObjectParameter (
+
+    @field:JsonProperty("values")
+    val propertyValues: kotlin.collections.List<kotlin.String>? = null
+
+)
+