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[Bug]: A2A HTTP protocol upgrade fails when using Otel auto instrumentation due Netty

Aperta
#690 9 commenti 0 reazioni 0 assegnatari Vedi su GitHub

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Valutazione

Difficoltà
4/5
Tempo stimato
3-5 giorni
Idoneità per principianti
45/100
Tipo di issue
Bug
Chiarezza
Specificata chiaramente
Stato di attività
Ferma

Direzione di ricerca

Il problema riguarda la negoziazione dell’upgrade HTTP/2 quando l’auto-strumentazione OTEL è abilitata. Esaminate il codice di comunicazione HTTP del client A2A, probabilmente in io.a2a.client.http.A2ACardResolver o in handler Netty/Vert.x correlati. Riproducete il problema eseguendo un’applicazione con l’OTEL Java agent e i debug JAVA_OPTS per vedere l’upgrade non riuscito. La correzione potrebbe richiedere l’adeguamento della strumentazione Netty o della configurazione del client per gestire correttamente l’upgrade con OTEL.

Scritto dal modello di indicizzazione a partire dal testo della issue.

Descrizione

What happened?

Related to this issue: https://github.com/a2aproject/a2a-java/issues/502

When adding OTEL auto instrumentation to my application, by using the Java OTEL agent, the A2A client fails to negotiate an upgrade to HTTP 2. Look below for the logs in the application:

The reason behind the issue:

The OTel Java agent's Netty bytecode instrumentation breaks Vert.x's HTTP/2 cleartext (h2c) upgrade handling. When Java's  HttpClient (used by the A2A SDK) sends Upgrade: h2c, the instrumented server drops the connection instead of responding with 101 Switching Protocols.

To fix the issue:

Added OTEL_INSTRUMENTATION_NETTY_ENABLED=false to the cooking-agent and delivery-agent K8s manifests. This disables only the
  Netty-level instrumentation while keeping higher-level Quarkus/Vert.x observability intact.

If you add the following JAVA_OPTS to your application, you can see the requests being created by the A2A library and how it fails to upgrade the connection only when OTEL instrumentation is on.

- name: JAVA_OPTS
   value: -Djdk.httpclient.HttpClient.log="errors,requests,headers,frames:control:data:window,ssl,trace,channel"
Relevant log output
Application Error:

 [io.quarkus.vertx.http.runtime.QuarkusErrorHandler] (executor-thread-2) HTTP Request to /mgmt/processOrder failed, error id: 1cdeb479-c8fe-41f0-9802-3fe3e05490ec-3:                         
  jakarta.enterprise.inject.CreationException: Error creating synthetic bean [aLyk-Wj_mwEcG8EdDSX8kol41oQ]: java.lang.RuntimeException: io.a2a.spec.A2AClientError: Failed to obtain agent     
  card                                                                                                                                                                                         
          at com.pizzavibe.store.workflows.PizzaOrderWorkflow_aLyk-Wj_mwEcG8EdDSX8kol41oQ_Synthetic_Bean.create(Unknown Source)                                                                
          at com.pizzavibe.store.workflows.PizzaOrderWorkflow_aLyk-Wj_mwEcG8EdDSX8kol41oQ_Synthetic_Bean.create(Unknown Source)                                                                
          at io.quarkus.arc.impl.AbstractSharedContext.createInstanceHandle(AbstractSharedContext.java:119)                                                                                    
          at io.quarkus.arc.impl.AbstractSharedContext$1.get(AbstractSharedContext.java:38)                                                                                                    
          at io.quarkus.arc.impl.AbstractSharedContext$1.get(AbstractSharedContext.java:35)                                                                                                    
          at io.quarkus.arc.generator.Default_jakarta_enterprise_context_ApplicationScoped_ContextInstances.ch24(Unknown Source)                                                               
          at io.quarkus.arc.generator.Default_jakarta_enterprise_context_ApplicationScoped_ContextInstances.computeIfAbsent(Unknown Source)                                                    
          at io.quarkus.arc.impl.AbstractSharedContext.get(AbstractSharedContext.java:35)                                                                                                      
          at io.quarkus.arc.impl.ClientProxies.getApplicationScopedDelegate(ClientProxies.java:23)                                                                                             
          at com.pizzavibe.store.workflows.PizzaOrderWorkflow_aLyk-Wj_mwEcG8EdDSX8kol41oQ_Synthetic_ClientProxy.arc$delegate(Unknown Source)                                                   
          at com.pizzavibe.store.workflows.PizzaOrderWorkflow_aLyk-Wj_mwEcG8EdDSX8kol41oQ_Synthetic_ClientProxy.processPizzaOrder(Unknown Source)                                              
          at com.pizzavibe.store.StoreMgmtResource.processOrder(StoreMgmtResource.java:48)                                                                                                     
          at com.pizzavibe.store.StoreMgmtResource$quarkusrestinvoker$processOrder_0f393797cf8d9883eee70376b7ab7d4e45e97c49.invoke(Unknown Source)                                             
          at org.jboss.resteasy.reactive.server.handlers.InvocationHandler.handle(InvocationHandler.java:29)                                                                                   
          at io.quarkus.resteasy.reactive.server.runtime.QuarkusResteasyReactiveRequestContext.invokeHandler(QuarkusResteasyReactiveRequestContext.java:190)                                   
          at org.jboss.resteasy.reactive.common.core.AbstractResteasyReactiveContext.run(AbstractResteasyReactiveContext.java:147)                                                             
          at io.quarkus.vertx.core.runtime.VertxCoreRecorder$15.runWith(VertxCoreRecorder.java:666)                                                                                            
          at org.jboss.threads.EnhancedQueueExecutor$Task.doRunWith(EnhancedQueueExecutor.java:2651)                                                                                           
          at org.jboss.threads.EnhancedQueueExecutor$Task.run(EnhancedQueueExecutor.java:2630)                                                                                                 
          at org.jboss.threads.EnhancedQueueExecutor.runThreadBody(EnhancedQueueExecutor.java:1622)                                                                                            
          at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run(EnhancedQueueExecutor.java:1589)                                                                                           
          at org.jboss.threads.DelegatingRunnable.run(DelegatingRunnable.java:11)                                                                                                              
          at org.jboss.threads.ThreadLocalResettingRunnable.run(ThreadLocalResettingRunnable.java:11)                                                                                          
          at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)                                                                                             
          at java.base/java.lang.Thread.run(Thread.java:1583)                                                                                                                                  
  Caused by: java.lang.RuntimeException: io.a2a.spec.A2AClientError: Failed to obtain agent card                                                                                               
          at dev.langchain4j.agentic.a2a.DefaultA2AClientBuilder.agentCard(DefaultA2AClientBuilder.java:83)                                                                                    
          at dev.langchain4j.agentic.a2a.DefaultA2AClientBuilder.<init>(DefaultA2AClientBuilder.java:63)                                                                                       
          at dev.langchain4j.agentic.a2a.DefaultA2AService.a2aBuilder(DefaultA2AService.java:24)                                                                                               
          at dev.langchain4j.agentic.AgenticServices.a2aBuilder(AgenticServices.java:271)                                                                                                      
          at dev.langchain4j.agentic.AgenticServices.createA2AClientAgent(AgenticServices.java:786)                                                                                            
          at dev.langchain4j.agentic.AgenticServices.createBuiltInAgentExecutor(AgenticServices.java:764)                                                                                      
          at dev.langchain4j.agentic.AgenticServices.createSubagent(AgenticServices.java:700)                                                                                                  
          at dev.langchain4j.agentic.AgenticServices.lambda$createSubagents$0(AgenticServices.java:694)                                                                                        
          at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)                                                                                               
          at java.base/java.util.Spliterators$ArraySpliterator.forEachRemaining(Spliterators.java:1024)                                                                                        
          at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)                                                                                                   
          at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)                                                                                            
          at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:575)                                                                                                   
          at java.base/java.util.stream.AbstractPipeline.evaluateToArrayNode(AbstractPipeline.java:260)                                                                                        
          at java.base/java.util.stream.ReferencePipeline.toArray(ReferencePipeline.java:616)                                                                                                  
          at java.base/java.util.stream.ReferencePipeline.toArray(ReferencePipeline.java:622)                                                                                                  
          at java.base/java.util.stream.ReferencePipeline.toList(ReferencePipeline.java:627)                                                                                                   
          at dev.langchain4j.agentic.AgenticServices.createSubagents(AgenticServices.java:695)                                                                                                 
          at dev.langchain4j.agentic.AgenticServices.buildSequentialAgent(AgenticServices.java:394)                                                                                            
          at dev.langchain4j.agentic.AgenticServices.createComposedAgent(AgenticServices.java:355)                                                                                             
          at dev.langchain4j.agentic.AgenticServices.createAgenticSystem(AgenticServices.java:324)                                                                                             
          at io.quarkiverse.langchain4j.agentic.runtime.AgenticRecorder$1.apply(AgenticRecorder.java:52)                                                                                       
          at io.quarkiverse.langchain4j.agentic.runtime.AgenticRecorder$1.apply(AgenticRecorder.java:36)                                                                                       
          at com.pizzavibe.store.workflows.PizzaOrderWorkflow_aLyk-Wj_mwEcG8EdDSX8kol41oQ_Synthetic_Bean.createSynthetic(Unknown Source)                                                       
          ... 25 more                                                                                                                                                                          
  Caused by: io.a2a.spec.A2AClientError: Failed to obtain agent card                                                                                                                           
          at io.a2a.client.http.A2ACardResolver.getAgentCard(A2ACardResolver.java:105)                                                                                                         
          at io.a2a.A2A.getAgentCard(A2A.java:187)                                                                                                                                             
          at io.a2a.A2A.getAgentCard(A2A.java:155)                                                                                                                                             
          at io.a2a.A2A.getAgentCard(A2A.java:142)                                                                                                                                             
          at dev.langchain4j.agentic.a2a.DefaultA2AClientBuilder.agentCard(DefaultA2AClientBuilder.java:81)                                                                                    
          ... 48 more                                                                                                                                                                          
  Caused by: java.io.IOException: HTTP/1.1 header parser received no bytes                                                                                                                     
          at java.net.http/jdk.internal.net.http.HttpClientImpl.send(HttpClientImpl.java:970)                                                                                                  
          at java.net.http/jdk.internal.net.http.HttpClientFacade.send(HttpClientFacade.java:133)                                                                                              
          at io.a2a.client.http.JdkA2AHttpClient$JdkGetBuilder.get(JdkA2AHttpClient.java:212)                                                                                                  
          at io.a2a.client.http.A2ACardResolver.getAgentCard(A2ACardResolver.java:99)                                                                                                          
          ... 52 more                                                                                                                                                                          
  Caused by: java.io.IOException: HTTP/1.1 header parser received no bytes                                                                                                                     
          at java.net.http/jdk.internal.net.http.common.Utils.wrapWithExtraDetail(Utils.java:412)                                                                                              
          at java.net.http/jdk.internal.net.http.Http1Response$HeadersReader.onReadError(Http1Response.java:590)                                                                               
          at java.net.http/jdk.internal.net.http.Http1AsyncReceiver.checkForErrors(Http1AsyncReceiver.java:302)                                                                                
          at java.net.http/jdk.internal.net.http.Http1AsyncReceiver.flush(Http1AsyncReceiver.java:268)                                                                                         
          at java.net.http/jdk.internal.net.http.common.SequentialScheduler$LockingRestartableTask.run(SequentialScheduler.java:182)                                                           
          at java.net.http/jdk.internal.net.http.common.SequentialScheduler$CompleteRestartableTask.run(SequentialScheduler.java:149)                                                          
          at java.net.http/jdk.internal.net.http.common.SequentialScheduler$SchedulableTask.run(SequentialScheduler.java:207)                                                                  
          at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)                                                                                         
          at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)                                                                                         
          ... 1 more                                                                                                                                                                           
  Caused by: java.io.EOFException: EOF reached while reading                                                                                                                                   
          at java.net.http/jdk.internal.net.http.Http1AsyncReceiver$Http1TubeSubscriber.onComplete(Http1AsyncReceiver.java:601)                                                                
          at java.net.http/jdk.internal.net.http.SocketTube$InternalReadPublisher$ReadSubscription.signalCompletion(SocketTube.java:648)                                                       
          at java.net.http/jdk.internal.net.http.SocketTube$InternalReadPublisher$InternalReadSubscription.read(SocketTube.java:853)                                                           
          at java.net.http/jdk.internal.net.http.SocketTube$SocketFlowTask.run(SocketTube.java:181)                                                                                            
          at java.net.http/jdk.internal.net.http.common.SequentialScheduler$SchedulableTask.run(SequentialScheduler.java:207)                                                                  
          at java.net.http/jdk.internal.net.http.common.SequentialScheduler.runOrSchedule(SequentialScheduler.java:280)                                                                        
          at java.net.http/jdk.internal.net.http.common.SequentialScheduler.runOrSchedule(SequentialScheduler.java:233)                                                                        
          at java.net.http/jdk.internal.net.http.SocketTube$InternalReadPublisher$InternalReadSubscription.signalReadable(SocketTube.java:782)                                                 
          at java.net.http/jdk.internal.net.http.SocketTube$InternalReadPublisher$ReadEvent.signalEvent(SocketTube.java:965)                                                                   
          at java.net.http/jdk.internal.net.http.SocketTube$SocketFlowEvent.handle(SocketTube.java:253)                                                                                        
          at java.net.http/jdk.internal.net.http.HttpClientImpl$SelectorManager.handleEvent(HttpClientImpl.java:1477)                                                                          
          at java.net.http/jdk.internal.net.http.HttpClientImpl$SelectorManager.lambda$run$3(HttpClientImpl.java:1422)                                                                         
          at java.base/java.util.ArrayList.forEach(ArrayList.java:1596)                                                                                                                        
          at java.net.http/jdk.internal.net.http.HttpClientImpl$SelectorManager.run(HttpClientImpl.java:1422)
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