SBT assembly falis - scala

Question

I am running a spark job through intellij. Job executes and gives me output. i need to take this job as jar file to server and run, but when i try to do sbt assembly it throws below error:
[error] Not a valid command: assembly
[error] Not a valid project ID: assembly
[error] Expected ':' (if selecting a configuration)
[error] Not a valid key: assembly
[error] assembly
my sbt version is 0.13.8
below is my build.sbt file:
import sbt._, Keys._
name := "mobilewalla"
version := "1.0"
scalaVersion := "2.11.7"
libraryDependencies ++= Seq("org.apache.spark" %% "spark-core" % "2.0.0",
"org.apache.spark" %% "spark-sql" % "2.0.0")
i added a file assembly.sbt under project dir. it contains:
addSbtPlugin("com.eed3si9n" % "sbt-assembly" % "0.14.3")
what am i missing here

Answer 1

Add these lines in your build.sbt
assemblyMergeStrategy in assembly := {
case PathList("META-INF", xs # _*) => MergeStrategy.discard
case x => MergeStrategy.first
}
mainClass in assembly := Some("com.SparkMain")
resolvers += "spray repo" at "http://repo.spray.io"
assemblyJarName in assembly := "streaming-api.jar"
and include these lines in your plugins.sbt file
addSbtPlugin("io.spray" % "sbt-revolver" % "0.7.2")
addSbtPlugin("com.eed3si9n" % "sbt-assembly" % "0.13.0")

Answer 2

To assemble the multiple jars to one u need add below plugin in plugins.sbt under project directory.
addSbtPlugin("com.eed3si9n" % "sbt-assembly" % "0.14.3")
If u need to customize the assembled jar to trigger specific MainClass take example assembly.sbt
import sbtassembly.Plugin.AssemblyKeys._
Project.inConfig(Compile)(baseAssemblySettings)
mainClass in (Compile, assembly) := Some("<main application name with package path>")
jarName in (Compile, assembly) := s"${name.value}-${version.value}-dist.jar"
//below is merge strategy to make what all file need to exclude or include
mergeStrategy in (Compile, assembly) <<= (mergeStrategy in (Compile, assembly)) {
(old) => {
case PathList(ps # _*) if ps.last endsWith ".html" =>MergeStrategy.first
case "META-INF/MANIFEST.MF" => MergeStrategy.discard
case x => old(x)
}
}