Hello guys,
I'm writing to you with a hope that you can help me with exception
handling.
Currently after a long time connection can be reset by peer. See stacktrace
below.
I've tried to add a custom ChannelHandler which Overrides exceptionCaught()
and add it in Driver#initializePipeline() see code below. Also has tried to
add a channel that can be obtained from DefaultNettyPlcConnection. And none
of them actualy was added to the pipeline where this exception was thrown.
plc4x version: 0.7.0
StatckTrace:
2020-09-16 13:50:03.340 WARN [nioEventLoopGroup-58-1]
[io.netty.channel.DefaultChannelPipeline] onUnhandledInboundException - 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.
java.io.IOException: Connection reset by peer
at java.base/sun.nio.ch.FileDispatcherImpl.read0(Native Method)
at java.base/sun.nio.ch.SocketDispatcher.read(SocketDispatcher.java:39)
at java.base/sun.nio.ch.IOUtil.readIntoNativeBuffer(IOUtil.java:276)
at java.base/sun.nio.ch.IOUtil.read(IOUtil.java:233)
at java.base/sun.nio.ch.IOUtil.read(IOUtil.java:223)
at java.base/sun.nio.ch.SocketChannelImpl.read(SocketChannelImpl.java:358)
at io.netty.buffer.PooledByteBuf.setBytes(PooledByteBuf.java:253)
at io.netty.buffer.AbstractByteBuf.writeBytes(AbstractByteBuf.java:1133)
at
io.netty.channel.socket.nio.NioSocketChannel.doReadBytes(NioSocketChannel.java:350)
at
io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:148)
at
io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:714)
at
io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:650)
at
io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:576)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:493)
at
io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:989)
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)
Driver#initializePipeline:
try {
final Channel channel =
channelFactory.createChannel(this.handler);
channelFactory.initializePipeline(channel.pipeline());
} catch (PlcConnectionException e) {
log.error("Failed to create channel");
}
ChannelHandler:
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause)
{
log.warn("ExceptionCaught in worker: ctx = [{}], cause = [{}, {}],
workerName = [{}]",
ctx, cause.getClass(), cause.getMessage(), workerName);
if (cause instanceof ConnectTimeoutException) {
log.warn("ConnectionTimeout caught: workerName = [{}]",
workerName);
}
if ((cause instanceof IOException) &&
cause.getMessage().contains("Connection reset by peer")) {
log.warn("Connection reset by peer caught: workerName = [{}]",
workerName);
} else {
log.info("Unexpected exception caught: workerName = [{}]",
workerName);
}
this.callback.accept(cause);
}
DefaultNettyPlcConnection#channel:
log.info("Trying to get connection channel: worker name = [{}]",
this.workerName);
final Channel channel = ((DefaultNettyPlcConnection)
this.connection).getChannel();
log.info("Channel obtained successfully. Adding custom
channelHandler to it: channel = [{}], workerName = [{}]", channel,
this.workerName);
channel.pipeline().addLast(this.channelHandler);
log.info("ChannelHandler added: channel = [{}], channelHandler =
[{}], workerName = [{}]", channel, this.channelHandler, this.workerName);
Kind regards,
Vlad
