如何在AWS EMR上使用sbt程序集在scala中创建单个jar？运行到不重复状态:在以下中找到不同的文件内容：

Question

我在AWS EMR集群中，我刚刚站了起来，编译了scala文件，并希望将其构建为程序集。但是，当我发出sbt程序集时，会遇到去重复错误。

根据https://medium.com/@tedherman/compile-scala-on-emr-cb77610559f0，我最初有一个符号链接，将我的库链接到usr火花罐；

ln -s /usr/lib/spark/jars lib

虽然我已经注意到我的代码通过了一个sbt编译，不管有没有这样。但是，我不明白为什么/如何解决sbt程序集欺骗错误。我还将注意到，按照本文的规定，我在引导操作中安装了sbt。

具有中的符号链接

有些判断似乎是明确的、精确的欺骗；例如：

[error] deduplicate: different file contents found in the following:
[error] /home/hadoop/.ivy2/cache/org.apache.parquet/parquet-jackson/jars/parquet-jackson-1.10.1.jar:shaded/parquet/org/codehaus/jackson/util/CharTypes.class
[error] /usr/lib/spark/jars/parquet-jackson-1.10.1-spark-amzn-1.jar:shaded/parquet/org/codehaus/jackson/util/CharTypes.class

其他的似乎是相互竞争的版本；

[error] deduplicate: different file contents found in the following:
[error] /home/hadoop/.ivy2/cache/org.apache.spark/spark-core_2.11/jars/spark-core_2.11-2.4.3.jar:org/spark_project/jetty/util/MultiPartOutputStream.class
[error] /usr/lib/spark/jars/spark-core_2.11-2.4.5-amzn-0.jar:org/spark_project/jetty/util/MultiPartOutputStream.class

我不明白为什么会有相互竞争的版本；或者是默认的版本，或者是我做了什么来介绍它们。

没有符号链接的

我想，如果我去掉这个，我会有更少的问题，虽然我仍然有欺骗(只是较少)；

[error] deduplicate: different file contents found in the following:
[error] /home/hadoop/.ivy2/cache/org.apache.hadoop/hadoop-yarn-api/jars/hadoop-yarn-api-2.6.5.jar:org/apache/hadoop/yarn/factory/providers/package-info.class
[error] /home/hadoop/.ivy2/cache/org.apache.hadoop/hadoop-yarn-common/jars/hadoop-yarn-common-2.6.5.jar:org/apache/hadoop/yarn/factory/providers/package-info.class

我不明白上面为什么是一个陷阱，考虑到一个是hadoop纱线-api-2.6.5.jar，另一个是hadoop-纱线-公共-2.6.5.jar。不同的名字，为什么被骗？

其他似乎是版本；

[error] deduplicate: different file contents found in the following:
[error] /home/hadoop/.ivy2/cache/javax.inject/javax.inject/jars/javax.inject-1.jar:javax/inject/Named.class
[error] /home/hadoop/.ivy2/cache/org.glassfish.hk2.external/javax.inject/jars/javax.inject-2.4.0-b34.jar:javax/inject/Named.class

有些有相同的文件名，但路径/罐子不同.

[error] deduplicate: different file contents found in the following:
[error] /home/hadoop/.ivy2/cache/org.apache.arrow/arrow-format/jars/arrow-format-0.10.0.jar:git.properties
[error] /home/hadoop/.ivy2/cache/org.apache.arrow/arrow-memory/jars/arrow-memory-0.10.0.jar:git.properties
[error] /home/hadoop/.ivy2/cache/org.apache.arrow/arrow-vector/jars/arrow-vector-0.10.0.jar:git.properties

这些也一样..。

[error] deduplicate: different file contents found in the following:
[error] /home/hadoop/.ivy2/cache/org.apache.spark/spark-catalyst_2.11/jars/spark-catalyst_2.11-2.4.3.jar:org/apache/spark/unused/UnusedStubClass.class
[error] /home/hadoop/.ivy2/cache/org.apache.spark/spark-core_2.11/jars/spark-core_2.11-2.4.3.jar:org/apache/spark/unused/UnusedStubClass.class
[error] /home/hadoop/.ivy2/cache/org.apache.spark/spark-graphx_2.11/jars/spark-graphx_2.11-2.4.3.jar:org/apache/spark/unused/UnusedStubClass.class

作为参考，其他一些信息

导入我的scala对象

import org.apache.spark.sql.SparkSession
import java.time.LocalDateTime
import com.amazonaws.regions.Regions
import com.amazonaws.services.secretsmanager.AWSSecretsManagerClientBuilder
import com.amazonaws.services.secretsmanager.model.GetSecretValueRequest
import org.json4s.{DefaultFormats, MappingException}
import org.json4s.jackson.JsonMethods._
import com.datarobot.prediction.spark.Predictors.{getPredictorFromServer, getPredictor}

我的build.sbt

libraryDependencies ++= Seq(
  "net.snowflake" % "snowflake-jdbc" % "3.12.5",
  "net.snowflake" % "spark-snowflake_2.11" % "2.7.1-spark_2.4",
  "com.datarobot" % "scoring-code-spark-api_2.4.3" % "0.0.19",
  "com.datarobot" % "datarobot-prediction" % "2.1.4",
  "com.amazonaws" % "aws-java-sdk-secretsmanager" % "1.11.789",
  "software.amazon.awssdk" % "regions" % "2.13.23"
) 

有什么想法？请给我建议。

Answer 1

您将需要一个mergeStrategy设置(文档)。

“随机示例：”

assemblyMergeStrategy in assembly := {
  case PathList("META-INF", _)       => MergeStrategy.discard
  case PathList("git.properties", _) => MergeStrategy.discard
  case "application.conf"            => MergeStrategy.concat
  case "reference.conf"              => MergeStrategy.concat
  case _                             => MergeStrategy.first
}