mpRestClient send multipart/form-data with List<EntityPart> asynchronous failed

[yooman00]

Describe the bug
Sending multipart/form-data with mpRestClient asynchronous @restclient (injected in CDI RequestScoped bean) results in exception

[INFO] [err] jakarta.ws.rs.WebApplicationException: Failure in downstream service
[INFO] [err] at ITClass.postMethod(OcrIT.java:104)
[INFO] [err] at ITClass$Proxy$_$$WeldSubclass.postMethod$$super(Unknown Source)
[INFO] [err] at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
[INFO] [err] at java.base/java.lang.reflect.Method.invoke(Method.java:580)
[INFO] [err] at org.jboss.weld.interceptor.proxy.TerminalAroundInvokeInvocationContext.proceedInternal(TerminalAroundInvokeInvocationContext.java:51)
[INFO] [err] at org.jboss.weld.interceptor.proxy.AroundInvokeInvocationContext.proceed(AroundInvokeInvocationContext.java:78)
[INFO] [err] at com.ibm.tx.jta.cdi.interceptors.TransactionalInterceptor$2.run(TransactionalInterceptor.java:176)
[INFO] [err] at [internal classes]
[INFO] [err] at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
[INFO] [err] at java.base/java.lang.reflect.Method.invoke(Method.java:580)
[INFO] [err] at org.jboss.weld.interceptor.reader.SimpleInterceptorInvocation$SimpleMethodInvocation.invoke(SimpleInterceptorInvocation.java:73)
[INFO] [err] at org.jboss.weld.interceptor.proxy.InterceptorMethodHandler.executeAroundInvoke(InterceptorMethodHandler.java:84)
[INFO] [err] at org.jboss.weld.interceptor.proxy.InterceptorMethodHandler.executeInterception(InterceptorMethodHandler.java:72)
[INFO] [err] at org.jboss.weld.interceptor.proxy.InterceptorMethodHandler.invoke(InterceptorMethodHandler.java:56)
[INFO] [err] at org.jboss.weld.bean.proxy.CombinedInterceptorAndDecoratorStackMethodHandler.invoke(CombinedInterceptorAndDecoratorStackMethodHandler.java:79)
[INFO] [err] at org.jboss.weld.bean.proxy.CombinedInterceptorAndDecoratorStackMethodHandler.invoke(CombinedInterceptorAndDecoratorStackMethodHandler.java:68)
[INFO] [err] at ITClass$Proxy$$$WeldSubclass.postMethod(Unknown Source)
[INFO] [err] at ITClass$Proxy$$$_WeldClientProxy.postMethod(Unknown Source)
[INFO] [err] at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
[INFO] [err] at java.base/java.lang.reflect.Method.invoke(Method.java:580)
[INFO] [err] at org.jboss.resteasy.core.MethodInjectorImpl.invoke(MethodInjectorImpl.java:170)
[INFO] [err] at [internal classes]
[INFO] [err] at org.jboss.resteasy.core.ResourceMethodInvoker.lambda$invokeOnTarget$2(ResourceMethodInvoker.java:474)
[INFO] [err] at org.jboss.resteasy.core.interception.jaxrs.PreMatchContainerRequestContext.filter(PreMatchContainerRequestContext.java:434)
[INFO] [err] at [internal classes]
[INFO] [err] at org.jboss.resteasy.core.SynchronousDispatcher.lambda$invoke$4(SynchronousDispatcher.java:261)
[INFO] [err] at org.jboss.resteasy.core.SynchronousDispatcher.lambda$preprocess$0(SynchronousDispatcher.java:161)
[INFO] [err] at org.jboss.resteasy.core.interception.jaxrs.PreMatchContainerRequestContext.filter(PreMatchContainerRequestContext.java:434)
[INFO] [err] at [internal classes]
[INFO] [err] at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:614)
[INFO] [err] at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1266)
[INFO] [err] at [internal classes]
[INFO] [err] at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
[INFO] [err] at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
[INFO] [err] at java.base/java.lang.Thread.run(Thread.java:1583)
[INFO] [err] Caused by: java.util.concurrent.CompletionException: jakarta.ws.rs.ProcessingException: RESTEASY004655: Unable to invoke request: jakarta.ws.rs.WebApplicationException: Unexpected entity instance: org.jboss.resteasy.plugins.providers.multipart.ResteasyEntityPartBuilder$EntityPartImpl
[INFO] [err] at java.base/java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:315)
[INFO] [err] at java.base/java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:320)
[INFO] [err] at java.base/java.util.concurrent.CompletableFuture.uniHandle(CompletableFuture.java:936)
[INFO] [err] at java.base/java.util.concurrent.CompletableFuture$UniHandle.tryFire(CompletableFuture.java:911)
[INFO] [err] at java.base/java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:510)
[INFO] [err] at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1773)
[INFO] [err] at org.jboss.resteasy.microprofile.client.impl.MpClientInvocation$Decorator.lambda$decorate$0(MpClientInvocation.java:93)
[INFO] [err] at org.jboss.resteasy.concurrent.ContextualExecutors.lambda$runnable$3(ContextualExecutors.java:313)
[INFO] [err] at io.openliberty.restfulWS.client.internal.ThreadContextAsyncTaskWrapper$3.run(ThreadContextAsyncTaskWrapper.java:70)
[INFO] [err] ... 3 more
[INFO] [err] Caused by: jakarta.ws.rs.ProcessingException: RESTEASY004655: Unable to invoke request: jakarta.ws.rs.WebApplicationException: Unexpected entity instance: org.jboss.resteasy.plugins.providers.multipart.ResteasyEntityPartBuilder$EntityPartImpl
[INFO] [err] at org.jboss.resteasy.client.jaxrs.engines.ManualClosingApacheHttpClient43Engine.invoke(ManualClosingApacheHttpClient43Engine.java:391)
[INFO] [err] at [internal classes]
[INFO] [err] at org.jboss.resteasy.client.jaxrs.internal.ClientInvocation.lambda$executorSubmit$9(ClientInvocation.java:829)
[INFO] [err] at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1768)
[INFO] [err] ... 6 more
[INFO] [err] Caused by: jakarta.ws.rs.WebApplicationException: Unexpected entity instance: org.jboss.resteasy.plugins.providers.multipart.ResteasyEntityPartBuilder$EntityPartImpl
[INFO] [err] at org.jboss.resteasy.plugins.providers.multipart.IBMMultipartListProvider.writeTo(IBMMultipartListProvider.java:150)
[INFO] [err] at [internal classes]
[INFO] [err] ... 9 more

Steps to Reproduce

• Enable Features:
  cdi-4.0
  mpRestClient-3.0
• Create a Rest Client with post form-data
  @post
  @path("/path")
  @produces(MediaType.APPLICATION_JSON)
  @consumes(MediaType.MULTIPART_FORM_DATA)
  CompletionStage postMethod(@HeaderParam("Authorization")String bearerToken, List parts) throws IOException, ProcessingException;
• Consume the service from RequestScoped bean
  ....
  restClient.postMethod().whenComplete(consumer);

Expected behavior
Expeected is multipart/form-data POST call to success the same way as a GET call

Diagnostic information:

• OpenLiberty Version: 24.0.0.5
• Affected feature: mpRestClient-3.0
• Java Version: OpenJDK 64-Bit Server VM Temurin-21.0.3+9 (build 21.0.3+9-LTS, mixed mode, sharing)
• server.xml server.xml.txt
• messages.log messages.log

Additional context
Add any other context about the problem here.