LIVY-97. Improve livy launch script

using command "livy-server start" to start livy server and "livy-server stop" to stop livy server.
LIVY_LOG_DIR is for log directory location and LIVY_PID_DIR is for pid location.

Closes #95

bin/livy-server

@@ -18,37 +18,151 @@
 #
 # Runs Livy server.
 
-set -e
 
-export LIVY_HOME=$(cd $(dirname $0)/.. && pwd)
-cd $LIVY_HOME
+usage="Usage: livy-server (start|stop)"
 
-LIBDIR="$LIVY_HOME/jars"
-if [ ! -d "$LIBDIR" ]; then
-  LIBDIR="$LIVY_HOME/server/target/jars"
-fi
-if [ ! -d "$LIBDIR" ]; then
-  echo "Could not find Livy jars directory." 1>&2
+# Find the java binary
+if [ -n "${JAVA_HOME}" ]; then
+  RUNNER="${JAVA_HOME}/bin/java"
+elif [ `command -v java` ]; then
+  RUNNER="java"
+else
+  echo "JAVA_HOME is not set" >&2
   exit 1
 fi
 
-if [ -z "$LIVY_CONF_DIR" ]; then
-  LIVY_CONF_DIR="$LIVY_HOME/conf"
+export LIVY_HOME=$(cd $(dirname $0)/.. && pwd)
+LIVY_CONF_DIR=${LIVY_CONF_DIR:-"$LIVY_HOME/conf"}
+
+if [ -f "${LIVY_CONF_DIR}/livy-env.sh" ]; then
+  # Promote all variable declarations to environment (exported) variables
+  set -a
+  . "${LIVY_CONF_DIR}/livy-env.sh"
+  set +a
 fi
 
-LIVY_CLASSPATH="$LIBDIR/*:$LIVY_CONF_DIR"
+LIVY_IDENT_STRING=${LIVY_IDENT_STRING:-"$USER"}
+LIVY_PID_DIR=${LIVY_PID_DIR:-"/tmp"}
+pid="$LIVY_PID_DIR/livy-$LIVY_IDENT_STRING-server.pid"
 
-if [ -n "$SPARK_CONF_DIR" ]; then
-  LIVY_CLASSPATH="$LIVY_CLASSPATH:$SPARK_CONF_DIR"
-fi
-if [ -n "$HADOOP_CONF_DIR" ]; then
-  LIVY_CLASSPATH="$LIVY_CLASSPATH:$HADOOP_CONF_DIR"
-fi
-if [ -n "$YARN_CONF_DIR" ]; then
-  LIVY_CLASSPATH="$LIVY_CLASSPATH:$YARN_CONF_DIR"
-fi
+livy_rotate_log () {
+  log=$1
+  num=${2:-5}
+  if [ -f "$log" ]; then # rotate logs
+	while [ $num -gt 1 ]; do
+	  prev=`expr $num - 1`
+	  [ -f "$log.$prev" ] && mv "$log.$prev" "$log.$num"
+	  num=$prev
+	done
+    mv "$log" "$log.$num"
+  fi
+}
+
+create_dir() {
+  dir_name=$1
+  dir_variable=$2
+  mkdir -p $dir_name
+  touch $dir_name/.test > /dev/null 2>&1
+  TEST_DIR=$?
+  if [ "${TEST_DIR}" = "0" ]; then
+    rm -f "$dir_name"/.test
+  else
+    echo "$USER doesn't have permission to write to directory: $dir_name which is $dir_variable"
+    exit 1
+  fi
+}
+
+start_livy_server() {
+
+  LIBDIR="$LIVY_HOME/jars"
+  if [ ! -d "$LIBDIR" ]; then
+    LIBDIR="$LIVY_HOME/server/target/jars"
+  fi
+  if [ ! -d "$LIBDIR" ]; then
+    echo "Could not find Livy jars directory." 1>&2
+    exit 1
+  fi
+
+  LIVY_CLASSPATH="$LIBDIR/*:$LIVY_CONF_DIR"
+
+  if [ -n "$SPARK_CONF_DIR" ]; then
+    LIVY_CLASSPATH="$LIVY_CLASSPATH:$SPARK_CONF_DIR"
+  fi
+  if [ -n "$HADOOP_CONF_DIR" ]; then
+    LIVY_CLASSPATH="$LIVY_CLASSPATH:$HADOOP_CONF_DIR"
+  fi
+  if [ -n "$YARN_CONF_DIR" ]; then
+    LIVY_CLASSPATH="$LIVY_CLASSPATH:$YARN_CONF_DIR"
+  fi
+
+  command="$RUNNER $LIVY_SERVER_JAVA_OPTS -cp $LIVY_CLASSPATH:$CLASSPATH com.cloudera.livy.server.LivyServer"
+
+  if [ $1 = "old" ]; then
+    exec $command
+  else
+    # get log directory
+    LIVY_LOG_DIR=${LIVY_LOG_DIR:-${LIVY_HOME}/logs}
+    create_dir $LIVY_LOG_DIR "LIVY_LOG_DIR"
+    create_dir $LIVY_PID_DIR "LIVY_PID_DIR"
+    log="$LIVY_LOG_DIR/livy-$LIVY_IDENT_STRING-server.out"
+    # Set default scheduling priority
+    LIVY_NICENESS=${LIVY_NICENESS:-0}
+    if [ -f "$pid" ]; then
+      TARGET_ID="$(cat "$pid")"
+      if [[ $(ps -p "$TARGET_ID" -o comm=) =~ "java" ]]; then
+        echo "livy_server running as process $TARGET_ID.  Stop it first."
+        exit 1
+      fi
+    fi
+
+    livy_rotate_log "$log"
+    echo "starting $command, logging to $log"
+    nohup nice -n "$LIVY_NICENESS" $command >> "$log" 2>&1 < /dev/null &
+    newpid="$!"
+    echo "$newpid" > "$pid"
+    sleep 2
+    # Check if the process has died; in that case we'll tail the log so the user can see
+    if [[ ! $(ps -p "$newpid" -o comm=) =~ "java" ]]; then
+      echo "failed to launch $command:"
+      tail -2 "$log" | sed 's/^/  /'
+      echo "full log in $log"
+      rm -rf "$pid"
+    fi
+  fi
+}
+
+option=$1
+
+case $option in
+
+  (start)
+    start_livy_server "new"
+    ;;
+
+  ("")
+    # make it compatible with previous version of livy-server
+    start_livy_server "old"
+    ;;
+
+  (stop)
+
+    if [ -f $pid ]; then
+      TARGET_ID="$(cat "$pid")"
+      if [[ $(ps -p "$TARGET_ID" -o comm=) =~ "java" ]]; then
+        echo "stopping livy_server"
+        kill "$TARGET_ID" && rm -f "$pid"
+      else
+        echo "no livy_server to stop"
+      fi
+    else
+      echo "no livy_server to stop"
+    fi
+    ;;
+
+  (*)
+    echo $usage
+    exit 1
+    ;;
+
+esac
 
-exec java \
-	$LIVY_SERVER_JAVA_OPTS \
-	-cp "$LIVY_CLASSPATH:$CLASSPATH" \
-	com.cloudera.livy.server.LivyServer

conf/livy-env.sh

@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+#
+# Licensed to Cloudera, Inc. under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  Cloudera, Inc. licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# LIVY ENVIRONMENT VARIABLE
+#
+# - SPARK_HOME      Spark which you would like to use in livy
+# - LIVY_LOG_DIR    Where log files are stored.  (Default: ${LIVY_HOME}/logs)
+# - LIVY_PID_DIR    Where the pid file is stored. (Default: /tmp)
+# - LIVY_SERVER_JAVA_OPTS  Java Opts for running livy server (You can set jvm related setting here, like jvm memory/gc algorithm and etc.)