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[BUG][kotlin-client][multiplatform] "NoSuchMethodError" in runtime when starting ktor server with Kotlin 1.5.10

See original GitHub issue

Bug Report Checklist

Have you provided a full/minimal spec to reproduce the issue?
Have you validated the input using an OpenAPI validator (example)?
Have you tested with the latest master to confirm the issue still exists?
Have you searched for related issues/PRs?
What’s the actual output vs expected output?
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Description

When generating a Kotlin client using the multiplatform approach, the generated module builds fine, but it fails in runtime when I consume it from my project that includes a ktor server. It fails at the moment of installing ContentNegotiation feature:

fun Application.module() {
    install(ContentNegotiation) { // <<<<<<<<<<<< FAILS HERE
        json()
    }
}

The exact stack trace:

$ ./gradlew run                                                                                                                                                                                                                                                                                    
                                                                                                                                                                                                                                                                                                                                                                              
> Configure project :generated-client                                                                                                                                                                                                                                                                                                                                         
Kotlin Multiplatform Projects are an experimental feature.                                                                                                                                                                                                                                                                                                                    
                                                                                                                                                                                                                                                                                                                                                                              
Some Kotlin/Native targets cannot be built on this linux_x64 machine and are disabled:                                                                                                                                                                                                                                                                                        
    * In project ':':                                                                                                                                                                                                                                                                                                                                                         
        * targets 'iosArm64', 'iosX64' (can be built with a macos_x64 host)                                                                                                                                                                                                                                                                                                   
To hide this message, add 'kotlin.native.ignoreDisabledTargets=true' to the Gradle properties.                                                                                                                                                                                                                                                                                
                                                                                                                                                                                                                                                                                                                                                                              
                                                                                                                                                                                                                                                                                                                                                                              
> Task :backend:run FAILED                                                                                                                                                                                                                                                                                                                                                    
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".                                                                                                                                                                                                                                                                                                              
SLF4J: Defaulting to no-operation (NOP) logger implementation                                                                                                                                                                                                                                                                                                                 
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.                                                                                                                                                                                                                                                                                            
Exception in thread "main" java.lang.reflect.InvocationTargetException                                                                                                                                                                                                                                                                                                        
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)                                                                                                                                                                                                                                                                                     
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)                                                                                                                                                                                                                                                                   
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)                                                                                                                                                                                                                                                           
        at java.base/java.lang.reflect.Method.invoke(Method.java:566)                                                                                                                                                                                                                                                                                                         
        at kotlin.reflect.jvm.internal.calls.CallerImpl$Method.callMethod(CallerImpl.kt:97)                                                                                                                                                                                                                                                                                   
        at kotlin.reflect.jvm.internal.calls.CallerImpl$Method$Static.call(CallerImpl.kt:106)                                                                                                                                                                                                                                                                                 
        at kotlin.reflect.jvm.internal.KCallableImpl.call(KCallableImpl.kt:108)                                                                                                                                                                                                                                                                                               
        at kotlin.reflect.jvm.internal.KCallableImpl.callDefaultMethod$kotlin_reflection(KCallableImpl.kt:159)                                                                                                                                                                                                                                                                
        at kotlin.reflect.jvm.internal.KCallableImpl.callBy(KCallableImpl.kt:112)                                                                                                                                                                                                                                                                                             
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.callFunctionWithInjection(ApplicationEngineEnvironmentReloading.kt:406)                                                                                                                                                                                                                                
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.executeModuleFunction(ApplicationEngineEnvironmentReloading.kt:360)                                                                                                                                                                                                                                    
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.access$executeModuleFunction(ApplicationEngineEnvironmentReloading.kt:35)                                                                                                                                                                                                                              
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading$launchModuleByName$1.invoke(ApplicationEngineEnvironmentReloading.kt:311)                                                                                                                                                                                                                              
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading$launchModuleByName$1.invoke(ApplicationEngineEnvironmentReloading.kt:35)                                                                                                                                                                                                                               
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.avoidingDoubleStartupFor(ApplicationEngineEnvironmentReloading.kt:335)                                                                                                                                                                                                                                 
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.launchModuleByName(ApplicationEngineEnvironmentReloading.kt:310)                                                                                                                                                                                                                                       
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.access$launchModuleByName(ApplicationEngineEnvironmentReloading.kt:35)                                                                                                                                                                                                                                 
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading$instantiateAndConfigureApplication$1.invoke(ApplicationEngineEnvironmentReloading.kt:299)                                                                                                                                                                                                              
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading$instantiateAndConfigureApplication$1.invoke(ApplicationEngineEnvironmentReloading.kt:35)                                                                                                                                                                                                               
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.avoidingDoubleStartup(ApplicationEngineEnvironmentReloading.kt:317)                                                                                                                                                                                                                                    
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.instantiateAndConfigureApplication(ApplicationEngineEnvironmentReloading.kt:297)                                                                                                                                                                                                                       
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.createApplication(ApplicationEngineEnvironmentReloading.kt:138)                                                                                                                                                                                                                                        
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.start(ApplicationEngineEnvironmentReloading.kt:270)                                                                                                                                                                                                                                                    
        at io.ktor.server.cio.CIOApplicationEngine$serverJob$1$2.invokeSuspend(CIOApplicationEngine.kt:62)                                                                                                                                                                                                                                                                    
        at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)                                                                                      
        at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)                                                                                                                
        at kotlinx.coroutines.scheduling.CoroutineScheduler.runSafely(CoroutineScheduler.kt:571)                                                                                       
        at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.executeTask(CoroutineScheduler.kt:750)                                                                                                                                                                                                                                                                     
        at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:678)                                                                                                                                                                                                                                                                       
        at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:665)                                                                                      
Caused by: java.lang.NoSuchMethodError: 'kotlinx.serialization.json.Json kotlinx.serialization.json.JsonKt.Json$default(kotlinx.serialization.json.Json, kotlin.jvm.functions.Function1, int, java.lang.Object)'                                                                                                                                                              
        at io.ktor.serialization.JsonSupportKt.<clinit>(JsonSupport.kt:29)                                                                                                             
        at ExampleApplicationKt$module$1.invoke(ExampleApplication.kt:10)                                                                                                              
        at ExampleApplicationKt$module$1.invoke(ExampleApplication.kt:9)                                                                                                               
        at io.ktor.features.ContentNegotiation$Feature.install(ContentNegotiation.kt:104)                                                                                              
        at io.ktor.features.ContentNegotiation$Feature.install(ContentNegotiation.kt:97)                                                                                               
        at io.ktor.application.ApplicationFeatureKt.install(ApplicationFeature.kt:68)                                                                                                  
        at ExampleApplicationKt.module(ExampleApplication.kt:9)                                                                                                                        
        ... 30 more                                                                        
Exception in thread "DefaultDispatcher-worker-1" java.lang.reflect.InvocationTargetException                                 
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)                                                                                              
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)                                                                                                                                                                                                                                                                   
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)                                                                                                                                                                                                                                                           
        at java.base/java.lang.reflect.Method.invoke(Method.java:566)                                                                                                                  
        at kotlin.reflect.jvm.internal.calls.CallerImpl$Method.callMethod(CallerImpl.kt:97)                                                                                            
        at kotlin.reflect.jvm.internal.calls.CallerImpl$Method$Static.call(CallerImpl.kt:106)                                                                                          
        at kotlin.reflect.jvm.internal.KCallableImpl.call(KCallableImpl.kt:108)                                                                                                        
        at kotlin.reflect.jvm.internal.KCallableImpl.callDefaultMethod$kotlin_reflection(KCallableImpl.kt:159)                                                                                                                                                                                                                                                                
        at kotlin.reflect.jvm.internal.KCallableImpl.callBy(KCallableImpl.kt:112)                                                                                                      
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.callFunctionWithInjection(ApplicationEngineEnvironmentReloading.kt:406)                                                                                                                                                                                                                                
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.executeModuleFunction(ApplicationEngineEnvironmentReloading.kt:360)                                                                                                                                                                                                                                    
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.access$executeModuleFunction(ApplicationEngineEnvironmentReloading.kt:35)                                                                                                                                                                                                                              
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading$launchModuleByName$1.invoke(ApplicationEngineEnvironmentReloading.kt:311)                                                                                                                                                                                                                              
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading$launchModuleByName$1.invoke(ApplicationEngineEnvironmentReloading.kt:35)                                                                                                                                                                                                                               
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.avoidingDoubleStartupFor(ApplicationEngineEnvironmentReloading.kt:335)                                                                                                                                                                                                                                 
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.launchModuleByName(ApplicationEngineEnvironmentReloading.kt:310)                                                                                                                                                                                                                                       
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.access$launchModuleByName(ApplicationEngineEnvironmentReloading.kt:35)                                                                                                                                                                                                                                 
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading$instantiateAndConfigureApplication$1.invoke(ApplicationEngineEnvironmentReloading.kt:299)                                                                                                                                                                                                              
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading$instantiateAndConfigureApplication$1.invoke(ApplicationEngineEnvironmentReloading.kt:35)                                                                                                                                                                                                               
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.avoidingDoubleStartup(ApplicationEngineEnvironmentReloading.kt:317)                                                                                                                                                                                                                                    
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.instantiateAndConfigureApplication(ApplicationEngineEnvironmentReloading.kt:297)                                                                                                                                                                                                                       
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.createApplication(ApplicationEngineEnvironmentReloading.kt:138)                                                                                                                                                                                                                                        
        at io.ktor.server.engine.ApplicationEngineEnvironmentReloading.start(ApplicationEngineEnvironmentReloading.kt:270)                                                                                                                                                                                                                                                    
        at io.ktor.server.cio.CIOApplicationEngine$serverJob$1$2.invokeSuspend(CIOApplicationEngine.kt:62)                                                                                                                                                                                                                                                                    
        at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)                                                                                      
        at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)                                                                                                                
        at kotlinx.coroutines.scheduling.CoroutineScheduler.runSafely(CoroutineScheduler.kt:571)                                                                                       
        at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.executeTask(CoroutineScheduler.kt:750)                                                                                                                                                                                                                                                                     
        at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:678)                                                                                                                                                                                                                                                                       
        at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:665)                                                                                      
Caused by: java.lang.NoSuchMethodError: 'kotlinx.serialization.json.Json kotlinx.serialization.json.JsonKt.Json$default(kotlinx.serialization.json.Json, kotlin.jvm.functions.Function1, int, java.lang.Object)'                                                                                                                                                              
        at io.ktor.serialization.JsonSupportKt.<clinit>(JsonSupport.kt:29)                                                                                                             
        at ExampleApplicationKt$module$1.invoke(ExampleApplication.kt:10)                                                                                                              
        at ExampleApplicationKt$module$1.invoke(ExampleApplication.kt:9)                                                                                                               
        at io.ktor.features.ContentNegotiation$Feature.install(ContentNegotiation.kt:104)                                                                                              
        at io.ktor.features.ContentNegotiation$Feature.install(ContentNegotiation.kt:97)                                                                                               
        at io.ktor.application.ApplicationFeatureKt.install(ApplicationFeature.kt:68)                                                                                                  
        at ExampleApplicationKt.module(ExampleApplication.kt:9)                                                                                                                        
        ... 30 more

openapi-generator version

Tried 5.1.1 and 5.2.0-SNAPSHOT.

I’m trying it first time, so I don’t know if it’s a regression.

OpenAPI declaration file content or url

Irrelevant - the bug does not depend on the provided OpenAPI declaration. It manifests itself even if I remove all generated Kotlin code and leave only build.gradle + other build system config files.

Generation Details

I used this command:

java -jar openapi-generator-cli.jar generate \
   --generator-name kotlin \
   --input-spec https://petstore.swagger.io/v2/swagger.json \
   --library multiplatform \
   --output generated-client

Steps to reproduce

See the minimal project: https://github.com/krzema12/openapi-kotlin-multiplatform-issue-repro

Clone it and run ./gradlew run.

Related issues/PRs

This commit updates Kotlin version and related stuff, but in a different place: https://github.com/OpenAPITools/openapi-generator/commit/173a349e04880b4fbf27224a9a8e6632f528d681

Suggest a fix

Between Kotlin versions (1.3.x - 1.5.x), a lot has happened with kotlinx.serialization library, including backward-incompatible changes. Chances are there is some incompatibility which is not caught in compile time.

Assuming that the issue is caused primarily by including incorrect version(s) of some Kotlin-related libraries, fixing this issue needs to start from bumping the version(s) in https://github.com/OpenAPITools/openapi-generator/blob/173a349e04880b4fbf27224a9a8e6632f528d681/modules/openapi-generator/src/main/resources/kotlin-client/libraries/multiplatform/build.gradle.mustache and then adjusting the generated code accordingly.