首页 > 技术文章 > flink 问题记录

dongxiao-yang 2017-10-11 19:03 原文

 转发请注明原创地址:http://www.cnblogs.com/dongxiao-yang/p/7652337.html

1 WindowFunction类型不匹配无法编译。

flink 版本:1.3.0

参考https://ci.apache.org/projects/flink/flink-docs-release-1.3/dev/windows.html#windowfunction-with-incremental-aggregation写的demo发现reduce加入MyWindowFunction后编译不通过,报错参数类型不匹配。

代码如下

        MyReduceFunction a = new MyReduceFunction();
        
        

        DataStream<Tuple3<String, String, Integer>> counts4 = source

                .keyBy(0)
                .window(TumblingEventTimeWindows.of(Time
                        .of(1, TimeUnit.SECONDS)))
                .reduce(a,
                        new WindowFunction<Tuple2<String, Integer>, Tuple3<String, String, Integer>, String, TimeWindow>() {
                            private static final long serialVersionUID = 1L;

                            @Override
                            public void apply(
                                    String key,
                                    TimeWindow window,
                                    Iterable<Tuple2<String, Integer>> values,
                                    Collector<Tuple3<String, String, Integer>> out)
                                    throws Exception {
                                for (Tuple2<String, Integer> in : values) {
                                    out.collect(new Tuple3<>(in.f0, in.f0,
                                            in.f1));
                                }
                            }
                        });    



public static class MyReduceFunction implements
            ReduceFunction<Tuple2<String, Integer>> {

        @Override
        public Tuple2<String, Integer> reduce(Tuple2<String, Integer> value1,
                Tuple2<String, Integer> value2) throws Exception {
            // TODO Auto-generated method stub
            return new Tuple2<String, Integer>(value1.f0,
                    (value1.f1 + value2.f1));
        }

    }
View Code

  上述代码在reduce函数加入WindowFunction后代码一直报错,显示reduce函数包含的参数类型不匹配。其实原因出在keyBy(0)这个用法上,DataStream在调用public KeyedStream<T, Tuple> keyBy(int... fields) 和public KeyedStream<T, Tuple> keyBy(String... fields) 这两个方法的时候会调用

private KeyedStream<T, Tuple> keyBy(Keys<T> keys) {
return new KeyedStream<>(this, clean(KeySelectorUtil.getSelectorForKeys(keys,
getType(), getExecutionConfig())));
}

其中,KeySelectorUtil.getSelectorForKeys返回的是一个ComparableKeySelector类型的KeySelector,而这个类的定义为

   public static final class ComparableKeySelector<IN> implements KeySelector<IN, Tuple>, ResultTypeQueryable<Tuple> 

根据KeySelector的定义可知,ComparableKeySelector输出的所有key类型都为Tuple,所以上述WindowFunction设置的第三个泛型参数String是不对的。

 

解决办法

1 自定义KeySelector

    private static class TupleKeySelector implements
            KeySelector<Tuple2<String, Integer>, String> {

        @Override
        public String getKey(Tuple2<String, Integer> value) throws Exception {
            return value.f0;
        }
    }


        DataStream<Tuple3<String, String, Integer>> counts4 = source

                .keyBy(new TupleKeySelector())
View Code

上面首先定义了一个TupleKeySelector,返回Key类型为String,然后keyby的参数设置为对应的new TupleKeySelector(),表示keyStream根据一个String类型的Key分区

2  WindowFunction第三个Key泛型由String改为Tuple

 

参考问题:https://stackoverflow.com/questions/36917586/cant-apply-custom-functions-to-a-windowedstream-on-flink

 

2 flink-connector-elasticsearch5 接入问题

flink 版本:1.3.2

问题1:

java.lang.UnsupportedClassVersionError: org/elasticsearch/action/bulk/BulkProcessor$Listener : Unsupported major.minor version 52.0
	at java.lang.ClassLoader.defineClass1(Native Method)
	at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
	at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
	at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)

解决方案:这个问题是由于es5以后的版本要求最低的jdk版本是1.8,如果job的默认运行环境jdk低于1.8的话,需要手动指定java版本。

问题1.1:

设置env.java.home: /opt/jdk1.8.0_121 后上述错误依旧存在

目前看来env.java.home这个环境变量在使用yarn-cluster模式提交的情况下对container的JAVA_HOME是不起作用的

解决方案 :提交作业脚本增加-yD yarn.taskmanager.env.JAVA_HOME=/opt/jdk1.8.0_121 参数

参考文档为:https://ci.apache.org/projects/flink/flink-docs-release-1.1/setup/config.html#full-reference ,就是说这个参数在1.1的文档里提过,到了1.3反而没有了。。

 

问题2 :WebUI 500错误,yarn 日志报错

 ERROR org.apache.flink.runtime.webmonitor.files.StaticFileServerHandler  - Caught exception
java.lang.AbstractMethodError
at io.netty.util.ReferenceCountUtil.touch(ReferenceCountUtil.java:73)
at io.netty.channel.DefaultChannelPipeline.touch(DefaultChannelPipeline.java:107)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:356)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:351)
at io.netty.handler.codec.http.router.Handler.routed(Handler.java:62)
at io.netty.handler.codec.http.router.DualAbstractHandler.channelRead0(DualAbstractHandler.java:57)
at io.netty.handler.codec.http.router.DualAbstractHandler.channelRead0(DualAbstractHandler.java:20)
at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:105)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:373)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:359)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:351)
at org.apache.flink.runtime.webmonitor.HttpRequestHandler.channelRead0(HttpRequestHandler.java:105)
at org.apache.flink.runtime.webmonitor.HttpRequestHandler.channelRead0(HttpRequestHandler.java:65)
at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:105)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:373)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:359)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:351)
at io.netty.channel.ChannelInboundHandlerAdapter.channelRead(ChannelInboundHandlerAdapter.java:86)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:373)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:359)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:351)
at io.netty.channel.CombinedChannelDuplexHandler$DelegatingChannelHandlerContext.fireChannelRead(CombinedChannelDuplexHandler.java:435)
at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:293)
at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:267)
at io.netty.channel.CombinedChannelDuplexHandler.channelRead(CombinedChannelDuplexHandler.java:250)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:373)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:359)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:351)
at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1334)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:373)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:359)
at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:926)
at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:129)
at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:651)
at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:574)
at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:488)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:450)
at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:873)
at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:144)
at java.lang.Thread.run(Thread.java:745)

任务能够正常运行,但是点击ApplicationMaster进入webui的时候报500错误打不开,yarn错误日志如上。

这个问题是flink-connector-elasticsearch5包依赖了一个netty-commom的jar,这个包里面有一个io.netty.util.ReferenceCountUtil类和flink自带的netty-all同名类产生了冲突。

解决方案:netty-commom无法exclude,不然es运行时会缺其他的类,暂时的解决方案是把flink-streaming-java_2.10的<scope>provide</scope>给关掉,把flink原有的ReferenceCountUtil打进fat jar里面,覆盖掉上述错误的class。

        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-streaming-java_2.10</artifactId>
            <version>${flink.version}</version>
            <!-- <scope>provided</scope> -->
        </dependency>

        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-connector-elasticsearch5_2.10</artifactId>
            <version>${flink.version}</version>
        </dependency

 

3Flink 1.4.1支持yarn node-lable特性

1 手动合并https://github.com/apache/flink/pull/5593这个pr

2 pom文件里的hadoop.version升级到支持node-lable的yarn版本  <hadoop.version>2.8.2</hadoop.version>

 

4 Caused by: java.lang.ClassNotFoundException: javax.ws.rs.ext.MessageBodyReader

flink 版本 1.5.0

java.lang.NoClassDefFoundError: javax/ws/rs/ext/MessageBodyReader
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:763)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
at java.net.URLClassLoader$1.run(URLClassLoader.java:368)
at java.net.URLClassLoader$1.run(URLClassLoader.java:362)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:361)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:763)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
at java.net.URLClassLoader$1.run(URLClassLoader.java:368)
at java.net.URLClassLoader$1.run(URLClassLoader.java:362)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:361)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:763)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
at java.net.URLClassLoader$1.run(URLClassLoader.java:368)
at java.net.URLClassLoader$1.run(URLClassLoader.java:362)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:361)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at org.apache.hadoop.yarn.util.timeline.TimelineUtils.<clinit>(TimelineUtils.java:50)
at org.apache.hadoop.yarn.client.api.impl.YarnClientImpl.serviceInit(YarnClientImpl.java:179)
at org.apache.hadoop.service.AbstractService.init(AbstractService.java:163)
at org.apache.flink.yarn.cli.FlinkYarnSessionCli.getClusterDescriptor(FlinkYarnSessionCli.java:966)
at org.apache.flink.yarn.cli.FlinkYarnSessionCli.createDescriptor(FlinkYarnSessionCli.java:269)
at org.apache.flink.yarn.cli.FlinkYarnSessionCli.createClusterDescriptor(FlinkYarnSessionCli.java:444)
at org.apache.flink.yarn.cli.FlinkYarnSessionCli.createClusterDescriptor(FlinkYarnSessionCli.java:92)
at org.apache.flink.client.cli.CliFrontend.runProgram(CliFrontend.java:221)
at org.apache.flink.client.cli.CliFrontend.run(CliFrontend.java:210)
at org.apache.flink.client.cli.CliFrontend.parseParameters(CliFrontend.java:1020)
at org.apache.flink.client.cli.CliFrontend.lambda$main$14(CliFrontend.java:1096)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1836)
at org.apache.flink.runtime.security.HadoopSecurityContext.runSecured(HadoopSecurityContext.java:41)
at org.apache.flink.client.cli.CliFrontend.main(CliFrontend.java:1096)
Caused by: java.lang.ClassNotFoundException: javax.ws.rs.ext.MessageBodyReader
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 52 more

 

 打包启动后发现上述错误,解决办法是把flink-shade-hadoop2 pom文件里hadoop-yarn-common 这个依赖对于jersey-core的exclusion取消

<!--<exclusion>-->
<!--<groupId>com.sun.jersey</groupId>-->
<!--<artifactId>jersey-core</artifactId>-->
<!--</exclusion>-->

  

5 could not find implicit value for evidence parameter 

参考解释:https://www.iteblog.com/archives/2047.html

解决办法: import org.apache.flink.streaming.api.scala._

 

 

 

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