scala - unable to run web-app developed using scalatra scala

Question

I have developed a web app using scalatra 2.6.3 and scala 2.11.8 for the first time and it is not getting executed using jar. Below are my dependencies in build.sbt

scalaVersion := "2.11.8"
val scalatraVersion = "2.6.3"

dependencyOverrides += "com.fasterxml.jackson.core" % "jackson-core" % "2.9.4"
dependencyOverrides += "com.fasterxml.jackson.core" % "jackson-databind" % "2.9.4"
dependencyOverrides += "com.fasterxml.jackson.module" %% "jackson-module-scala" % "2.9.4"


libraryDependencies ++= Seq(
  "com.microsoft.sqlserver" % "mssql-jdbc" % "6.4.0.jre8", //Microsoft JDBC Driver For SQL Server
  "com.typesafe.play" %% "play-json" % "2.5.10",
  "com.typesafe" % "config" % "1.2.1", //Configuration
  "org.scalaj" %% "scalaj-http" % "2.3.0" % "compile",
  "org.apache.spark" %% "spark-core" % "2.2.0",
  "org.apache.spark" %% "spark-sql" % "2.2.0",
  "org.scala-lang" % "scala-library" % "${scala.version}",
  "org.apache.lucene" % "lucene-queryparser" % "7.2.1",
  "org.apache.lucene" % "lucene-queries" % "7.2.1",
  "org.apache.lucene" % "lucene-analyzers-common" % "7.2.1",
  "org.apache.lucene" % "lucene-codecs" % "7.2.1" ,
  "com.microsoft.azure" % "azure-storage" % "3.1.0",
  "com.microsoft.azure" % "azure-eventhubs" % "0.6.6",
  "org.apache.hadoop" % "hadoop-azure" % "2.7.0",
  "com.github.scala-incubator.io" %% "scala-io-file" % "0.4.3-1",
  "com.amazonaws" % "aws-java-sdk-logs" % "1.10.40",

  //Logging
  "org.slf4j" % "slf4j-api" % "1.7.25",
  "ch.qos.logback" % "logback-classic" % "1.2.3",

  "org.scalatra" %% "scalatra" % scalatraVersion,
  "org.scalatra" %% "scalatra-scalatest" % scalatraVersion % "test",
  "org.eclipse.jetty" % "jetty-webapp" % "9.4.10.RC1",
  "javax.servlet" % "javax.servlet-api" % "3.1.0" % "provided",
  "org.scalatra" %% "scalatra-scalate" % scalatraVersion
)

unmanagedResourceDirectories in Compile += { baseDirectory.value / "src/main/webapp" }
enablePlugins(ScalatraPlugin)

assemblyMergeStrategy in assembly := {

  case PathList("META-INF", xs @ _*) =>
    (xs map {_.toLowerCase}) match {
       case "services" :: xs =>
        MergeStrategy.first
      case _ => MergeStrategy.discard
    }
   case x => MergeStrategy.first
}

I know scalatra internally uses jetty to run App, I have setup webapp directory (src/main/webapp/) in project and I am able to run App in local using intellij but when I run it from jar file (created using sbt assembly) then it fails to find web app folder. Below is the code of Main app.

val server = {
  val listenPort = if (System.getenv.containsKey("PORT")) System.getenv.get("PORT").toShort else ConfigFactory.load.getString("api.port_num").toShort;
  logger.info("Listen Port: " + listenPort)
  new Server(listenPort)
}

val context: WebAppContext = new WebAppContext();
val webappDirLocation = "src/main/webapp/"
context.setServer(server)
context.setContextPath("/");
context.setDescriptor(webappDirLocation + "/WEB-INF/web.xml")
context.setResourceBase(webappDirLocation)
server.setHandler(context);

try {
  server.start()
  server.join()
} catch {
  case e: Exception => logger.error(s"Error occurred while starting App : $e")
    throw new RuntimeException(s"Unable to start App : $e")
}

Please suggest how to resolve this error, I am completely stuck at this. Tried below steps to resolve it, but no luck: -set war location using context.setWar method. -getting absolute path of src/main/webapp before setting in context

Thanks in advance!

标签： scalajettyembedded-jettyscalatrascalatra-sbt

Answer 1

如果您的程序集 jar 文件包含/WEB-INF/web.xml，您可以WebAppContext进行如下设置：

val context: WebAppContext = new WebAppContext()
val webXml = getClass.getResource("/WEB-INF/web.xml")

val webappDirLocation = if(webXml != null){
  // running the assembly jar
  webXml.toString.replaceFirst("/WEB-INF/web.xml$", "/")
} else {
  // running on the source tree
  "src/main/webapp/"
}

context.setResourceBase(webappDirLocation)
context.setDescriptor(webappDirLocation + "WEB-INF/web.xml")

在上面的示例中，配置被切换，因为它需要不同的配置来运行源代码树和运行程序集 jar。

此外，请注意，您需要添加以下行以通过 sbt-assembly-pluginbuild.sbt包含到您的程序集 jar 文件中：webapp/*

unmanagedResourceDirectories in Compile += { baseDirectory.value / "src/main/webapp" }