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Sto scrivendo un'applicazione in Scala che utilizza Spark. Sto confezionando l'app utilizzando Maven e riscontra problemi durante la costruzione di un "uber" or "fat" jar.Confezione ed esecuzione di Scala Spark Project con Maven
Il problema che sto affrontando è che l'applicazione funziona bene all'interno di un IDE o se fornisco una versione non uber-jar delle dipendenze come il percorso di classe java, ma non funziona il jar uber come percorso classe, ovvero
java -Xmx2G -cp target/spark-example-0.1-SNAPSHOT-jar-with-dependencies.jar debug.spark_example.Example data.txt
non funziona. Ottengo il seguente messaggio di errore:
ERROR SparkContext: Error initializing SparkContext.
com.typesafe.config.ConfigException$Missing: No configuration setting found for key 'akka.version'
at com.typesafe.config.impl.SimpleConfig.findKey(SimpleConfig.java:124)
at com.typesafe.config.impl.SimpleConfig.find(SimpleConfig.java:145)
at com.typesafe.config.impl.SimpleConfig.find(SimpleConfig.java:151)
at com.typesafe.config.impl.SimpleConfig.find(SimpleConfig.java:159)
at com.typesafe.config.impl.SimpleConfig.find(SimpleConfig.java:164)
at com.typesafe.config.impl.SimpleConfig.getString(SimpleConfig.java:206)
at akka.actor.ActorSystem$Settings.<init>(ActorSystem.scala:168)
at akka.actor.ActorSystemImpl.<init>(ActorSystem.scala:504)
at akka.actor.ActorSystem$.apply(ActorSystem.scala:141)
at akka.actor.ActorSystem$.apply(ActorSystem.scala:118)
at org.apache.spark.util.AkkaUtils$.org$apache$spark$util$AkkaUtils$$doCreateActorSystem(AkkaUtils.scala:122)
at org.apache.spark.util.AkkaUtils$$anonfun$1.apply(AkkaUtils.scala:54)
at org.apache.spark.util.AkkaUtils$$anonfun$1.apply(AkkaUtils.scala:53)
at org.apache.spark.util.Utils$$anonfun$startServiceOnPort$1.apply$mcVI$sp(Utils.scala:1991)
at scala.collection.immutable.Range.foreach$mVc$sp(Range.scala:160)
at org.apache.spark.util.Utils$.startServiceOnPort(Utils.scala:1982)
at org.apache.spark.util.AkkaUtils$.createActorSystem(AkkaUtils.scala:56)
at org.apache.spark.rpc.akka.AkkaRpcEnvFactory.create(AkkaRpcEnv.scala:245)
at org.apache.spark.rpc.RpcEnv$.create(RpcEnv.scala:52)
at org.apache.spark.SparkEnv$.create(SparkEnv.scala:247)
at org.apache.spark.SparkEnv$.createDriverEnv(SparkEnv.scala:188)
at org.apache.spark.SparkContext.createSparkEnv(SparkContext.scala:267)
at org.apache.spark.SparkContext.<init>(SparkContext.scala:424)
at debug.spark_example.Example$.main(Example.scala:9)
at debug.spark_example.Example.main(Example.scala)
Vorrei davvero apprezzare aiuto per capire quello che ho bisogno di aggiungere al file pom.xml e perché ho bisogno di aggiungere per ottenere questo al lavoro.
Ho cercato on-line ed ha trovato le seguenti risorse, che ho provato (vedere nel POM), ma non sono riuscito a mettersi al lavoro:
1) Spark utente Mailing list: http://apache-spark-user-list.1001560.n3.nabble.com/Packaging-a-spark-job-using-maven-td5615.html
2) how to package spark scala application
ho un semplice esempio che illustra il problema, un semplice progetto di classe 1 (src/main/Scala/debug/spark_example/Example.scala):
package debug.spark_example
import org.apache.spark.{SparkConf, SparkContext}
object Example {
def main(args: Array[String]): Unit = {
val sc = new SparkContext(new SparkConf().setAppName("Test").setMaster("local[2]"))
val lines = sc.textFile(args(0))
val lineLengths = lines.map(s => s.length)
val totalLength = lineLengths.reduce((a, b) => a + b)
lineLengths.foreach(println)
println(totalLength)
}
}
Ecco il file pom.xml:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>debug.spark-example</groupId>
<artifactId>spark-example</artifactId>
<version>0.1-SNAPSHOT</version>
<inceptionYear>2015</inceptionYear>
<properties>
<scala.majorVersion>2.11</scala.majorVersion>
<scala.minorVersion>.2</scala.minorVersion>
<spark.version>1.4.1</spark.version>
</properties>
<repositories>
<repository>
<id>scala-tools.org</id>
<name>Scala-Tools Maven2 Repository</name>
<url>http://scala-tools.org/repo-releases</url>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>scala-tools.org</id>
<name>Scala-Tools Maven2 Repository</name>
<url>http://scala-tools.org/repo-releases</url>
</pluginRepository>
</pluginRepositories>
<dependencies>
<dependency>
<groupId>org.scala-lang</groupId>
<artifactId>scala-library</artifactId>
<version>${scala.majorVersion}${scala.minorVersion}</version>
</dependency>
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-core_${scala.majorVersion}</artifactId>
<version>${spark.version}</version>
</dependency>
</dependencies>
<build>
<sourceDirectory>src/main/scala</sourceDirectory>
<plugins>
<plugin>
<groupId>org.scala-tools</groupId>
<artifactId>maven-scala-plugin</artifactId>
<executions>
<execution>
<goals>
<goal>compile</goal>
<goal>testCompile</goal>
</goals>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-eclipse-plugin</artifactId>
<configuration>
<downloadSources>true</downloadSources>
<buildcommands>
<buildcommand>ch.epfl.lamp.sdt.core.scalabuilder</buildcommand>
</buildcommands>
<additionalProjectnatures>
<projectnature>ch.epfl.lamp.sdt.core.scalanature</projectnature>
</additionalProjectnatures>
<classpathContainers>
<classpathContainer>org.eclipse.jdt.launching.JRE_CONTAINER</classpathContainer>
<classpathContainer>ch.epfl.lamp.sdt.launching.SCALA_CONTAINER</classpathContainer>
</classpathContainers>
</configuration>
</plugin>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<version>2.4</version>
<executions>
<execution>
<id>make-assembly</id>
<phase>package</phase>
<goals>
<goal>attached</goal>
</goals>
</execution>
</executions>
<configuration>
<tarLongFileMode>gnu</tarLongFileMode>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>2.2</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<minimizeJar>false</minimizeJar>
<createDependencyReducedPom>false</createDependencyReducedPom>
<artifactSet>
<includes>
<!-- Include here the dependencies you want to be packed in your fat jar -->
<include>*:*</include>
</includes>
</artifactSet>
<filters>
<filter>
<artifact>*:*</artifact>
<excludes>
<exclude>META-INF/*.SF</exclude>
<exclude>META-INF/*.DSA</exclude>
<exclude>META-INF/*.RSA</exclude>
</excludes>
</filter>
</filters>
<transformers>
<transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
<resource>reference.conf</resource>
</transformer>
</transformers>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.7</version>
<configuration>
<skipTests>true</skipTests>
</configuration>
</plugin>
</plugins>
</build>
<reporting>
<plugins>
<plugin>
<groupId>org.scala-tools</groupId>
<artifactId>maven-scala-plugin</artifactId>
</plugin>
</plugins>
</reporting>
</project>
Molte grazie in anticipo per il vostro aiuto.
Puoi approfondire non funziona? – Holden
@Holden Ho aggiunto il messaggio di errore che sto ottenendo alla domanda. Grazie per l'attenzione! – br19
Hai esaminato le istruzioni per l'ombra di Akka: http://doc.akka.io/docs/akka/snapshot/general/configuration.html. – Edmon