解决gremlin-dirver访问tinkerpop服务器提示序列化错误

 解决gremlin-dirver访问tinkerpop服务器提示序列化错误

问题描述

程序集成了gremlin-driver，访问远程tinkerpop服务器，在执行创建节点操作时，返回如下错误栈：

2017-08-17 15:25:27.519 ERROR 13548 --- [n-driver-loop-3] o.a.t.g.d.Handler$GremlinResponseHandler : Could not process the response

io.netty.handler.codec.DecoderException: org.apache.tinkerpop.gremlin.driver.ser.SerializationException: org.apache.tinkerpop.shaded.kryo.KryoException: Encountered unregistered class ID: 65536
Serialization trace:
id (org.apache.tinkerpop.gremlin.structure.util.detached.DetachedVertexProperty)
    at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:98)
    at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:366)
    at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:352)
    at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:345)
    at org.apache.tinkerpop.gremlin.driver.handler.WebSocketClientHandler.channelRead0(WebSocketClientHandler.java:91)
    at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:105)
    at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:366)
    at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:352)
    at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:345)
    at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:293)
    at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:267)
    at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:366)
    at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:352)
    at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:345)
    at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1294)
    at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:366)
    at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:352)
    at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:911)
    at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:131)
    at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:572)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:513)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:427)
    at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:399)
    at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:140)
    at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.tinkerpop.gremlin.driver.ser.SerializationException: org.apache.tinkerpop.shaded.kryo.KryoException: Encountered unregistered class ID: 65536

分析

从错误提示中可以猜到是kryo序列化出了问题，在处理vertex时出现了未注册类。这是考虑序列化的原理，kryo将结果从JanusGraph中序列化到Tinkerpop，再通过网络发送到应用，出现未注册类的情况肯定是应用端反序列化时无法找到对应类。因此考虑如何将类注册到kryo中去。

解决：

注册类：org.janusgraph.graphdb.relations.RelationIdentifier到配置文件中去。

hosts: [192.168.66.xxx]
port: 8182
serializer: { className: org.apache.tinkerpop.gremlin.driver.ser.GryoMessageSerializerV1d0, config: { serializeResultToString: false, custom: [org.janusgraph.graphdb.relations.RelationIdentifier] }}