ClassCastException: class org.apache.plc4x.java.opcua.readwrite.ServiceFault cannot be cast to class org.apache.plc4x.java.opcua.readwrite.ReadResponse

[Torsten Uhr]

Hi all,

if I create an OPCUA connection (to milo) and wait 5 minutes before sending a 
read request the error attached below is logged and the read execution blocks 
infinitely.
I'm used codebase 0.9.0 and 0.10.0 snapshot.
Note: The wait simulates a connection created earlier and get from a connection 
pool in a managed environment like application server.
I think theres a timeout for pending connections on the server side. I would 
expect, that the driver should throw an exception rather blocking?

[nioEventLoopGroup-2-1] WARN io.netty.channel.DefaultChannelPipeline - An 
exceptionCaught() event was fired, and it reached at the tail of the pipeline. 
It usually means the last handler in the pipeline did not handle the exception.
io.netty.handler.codec.DecoderException: java.lang.ClassCastException: class 
org.apache.plc4x.java.opcua.readwrite.ServiceFault cannot be cast to class 
org.apache.plc4x.java.opcua.readwrite.ReadResponse 
(org.apache.plc4x.java.opcua.readwrite.ServiceFault and 
org.apache.plc4x.java.opcua.readwrite.ReadResponse are in unnamed module of 
loader 'app')
        at 
io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:98)
        at 
io.netty.handler.codec.MessageToMessageCodec.channelRead(MessageToMessageCodec.java:111)
        at 
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
        at 
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
        at 
io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
        at 
io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:324)
        at 
io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:296)
        at 
io.netty.handler.codec.ByteToMessageCodec.channelRead(ByteToMessageCodec.java:103)
        at 
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
        at 
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
        at 
io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
        at 
io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1410)
        at 
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
        at 
io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
        at 
io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:919)
        at 
io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:166)
        at 
io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:719)
        at 
io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:655)
        at 
io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:581)
        at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:493)
        at 
io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:986)
        at 
io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
        at 
io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
        at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: java.lang.ClassCastException: class 
org.apache.plc4x.java.opcua.readwrite.ServiceFault cannot be cast to class 
org.apache.plc4x.java.opcua.readwrite.ReadResponse 
(org.apache.plc4x.java.opcua.readwrite.ServiceFault and 
org.apache.plc4x.java.opcua.readwrite.ReadResponse are in unnamed module of 
loader 'app')
        at 
org.apache.plc4x.java.opcua.protocol.OpcuaProtocolLogic.lambda$read$0(OpcuaProtocolLogic.java:177)
        at 
org.apache.plc4x.java.opcua.context.SecureChannel.lambda$4(SecureChannel.java:212)
        at 
org.apache.plc4x.java.spi.Plc4xNettyWrapper.decode(Plc4xNettyWrapper.java:175)
        at 
io.netty.handler.codec.MessageToMessageCodec$2.decode(MessageToMessageCodec.java:81)
        at 
io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:88)
        ... 23 more


JUnit regeression test:

import org.apache.plc4x.java.PlcDriverManager;
import org.apache.plc4x.java.api.PlcConnection;
import org.apache.plc4x.java.api.messages.PlcReadRequest;
import org.junit.Assert;
import org.junit.jupiter.api.Test;

public class RegressionTest
{
   @Test
   public void Timeout()
   {
      String connectionString = 
"opcua:tcp://localhost:12686/milo?discovery=false";
      final int TIMEOUT = 300 * 1000;

      try (PlcConnection plcConnection = new PlcDriverManager().getConnection( 
connectionString ))
      {
         Thread.sleep( TIMEOUT );

         PlcReadRequest.Builder builder = plcConnection.readRequestBuilder();
         builder.addItem("value", "ns=2;s=HelloWorld/ScalarTypes/String");

         builder.build().execute().get();
      }
      catch( Throwable thr )
      {
         Assert.fail( thr.getMessage() );
      }
   }
}


With best regards
Torsten Uhr