LIVY-119. Move LivyConf to the server module.

The core module is small and, after some other adjustments to dependencies,
can probably be removed. LivyConf is only used in the server module (except
for a single static field, now moved to ClientConf), so move it there.

Closes #111

client-common/src/main/java/com/cloudera/livy/client/common/ClientConf.java

@@ -52,6 +52,8 @@ public abstract class ClientConf<T extends ClientConf>
 
   private static final Map<String, TimeUnit> TIME_SUFFIXES;
 
+  public static final boolean TEST_MODE = Boolean.parseBoolean(System.getenv("livy.test"));
+
   static {
     TIME_SUFFIXES = new HashMap<>();
     TIME_SUFFIXES.put("us", TimeUnit.MICROSECONDS);

core/src/main/scala/com/cloudera/livy/Utils.scala

@@ -46,17 +46,6 @@ object Utils {
     }
   }
 
-  def getLivyConfDir(env: Map[String, String] = sys.env): Option[File] = {
-    env.get("LIVY_CONF_DIR")
-      .orElse(env.get("LIVY_HOME").map(path => s"$path${File.separator}conf"))
-      .map(new File(_))
-      .filter(_.exists())
-  }
-
-  def getLivyConfigFile(name: String): Option[File] = {
-    getLivyConfDir().map(new File(_, name)).filter(_.exists())
-  }
-
   /**
    * Checks if event has occurred during some time period. This performs an exponential backoff
    * to limit the poll calls.

repl/src/main/scala/com/cloudera/livy/repl/python/PythonInterpreter.scala

@@ -32,7 +32,7 @@ import org.json4s.jackson.JsonMethods._
 import org.json4s.jackson.Serialization.write
 import py4j.GatewayServer
 
-import com.cloudera.livy.LivyConf
+import com.cloudera.livy.client.common.ClientConf
 import com.cloudera.livy.repl.Interpreter
 import com.cloudera.livy.repl.process.ProcessInterpreter
 
@@ -50,8 +50,8 @@ object PythonInterpreter extends Logging {
 
     val pythonPath = sys.env.getOrElse("PYTHONPATH", "")
       .split(File.pathSeparator)
-      .++(if (!LivyConf.TEST_MODE) findPySparkArchives() else Nil)
-      .++(if (!LivyConf.TEST_MODE) findPyFiles() else Nil)
+      .++(if (!ClientConf.TEST_MODE) findPySparkArchives() else Nil)
+      .++(if (!ClientConf.TEST_MODE) findPyFiles() else Nil)
 
     env.put("PYTHONPATH", pythonPath.mkString(File.pathSeparator))
     env.put("PYTHONUNBUFFERED", "YES")

repl/src/main/scala/com/cloudera/livy/repl/sparkr/SparkRInterpreter.scala

@@ -33,7 +33,7 @@ import org.apache.spark.util.{ChildFirstURLClassLoader, MutableURLClassLoader, U
 import org.json4s._
 import org.json4s.JsonDSL._
 
-import com.cloudera.livy.LivyConf
+import com.cloudera.livy.client.common.ClientConf
 import com.cloudera.livy.repl
 import com.cloudera.livy.repl.Interpreter
 import com.cloudera.livy.repl.process.ProcessInterpreter
@@ -98,7 +98,7 @@ object SparkRInterpreter {
         // local mode
         val rLibPath = new File(sys.env.getOrElse("SPARKR_PACKAGE_DIR",
           Seq(sys.env.getOrElse("SPARK_HOME", "."), "R", "lib").mkString(File.separator)))
-        if (!LivyConf.TEST_MODE) {
+        if (!ClientConf.TEST_MODE) {
           require(rLibPath.exists(), "Cannot find sparkr package directory.")
           packageDir = rLibPath.getAbsolutePath()
         }
@@ -139,7 +139,7 @@ class SparkRInterpreter(process: Process)
   final override protected def waitUntilReady(): Unit = {
     // Set the option to catch and ignore errors instead of halting.
     sendRequest("options(error = dump.frames)")
-    if (!LivyConf.TEST_MODE) {
+    if (!ClientConf.TEST_MODE) {
       sendRequest("library(SparkR)")
       sendRequest("sc <- sparkR.init()")
     }

core/src/main/scala/com/cloudera/livy/LivyConf.scala → server/src/main/scala/com/cloudera/livy/LivyConf.scala

@@ -35,7 +35,7 @@ object LivyConf {
     def apply(key: String, dflt: Long): Entry = Entry(key, dflt: JLong)
   }
 
-  val TEST_MODE = sys.env.get("livy.test").map(_.toBoolean).getOrElse(false)
+  val TEST_MODE = ClientConf.TEST_MODE
 
   val SESSION_FACTORY = Entry("livy.server.session.factory", "process")
   val SPARK_HOME = Entry("livy.server.spark-home", null)
@@ -68,7 +68,7 @@ class LivyConf(loadDefaults: Boolean) extends ClientConf[LivyConf](null) {
   }
 
   def loadFromFile(name: String): LivyConf = {
-    Utils.getLivyConfigFile(name)
+    getConfigFile(name)
       .map(Utils.getPropertiesFromFile)
       .foreach(loadFromMap)
     this
@@ -87,6 +87,17 @@ class LivyConf(loadDefaults: Boolean) extends ClientConf[LivyConf](null) {
   /** Return the list of superusers. */
   def superusers(): Seq[String] = _superusers
 
+  private val configDir: Option[File] = {
+    sys.env.get("LIVY_CONF_DIR")
+      .orElse(sys.env.get("LIVY_HOME").map(path => s"$path${File.separator}conf"))
+      .map(new File(_))
+      .filter(_.exists())
+  }
+
+  private def getConfigFile(name: String): Option[File] = {
+    configDir.map(new File(_, name)).filter(_.exists())
+  }
+
   private def loadFromMap(map: Iterable[(String, String)]): Unit = {
     map.foreach { case (k, v) =>
       if (k.startsWith("livy.")) {