From 02235262de230481af3d193ef8a26a3808ceb3f3 Mon Sep 17 00:00:00 2001
From: Kyrill Poole <kyrill@pancentric.com>
Date: Tue, 5 May 2015 09:39:21 +0100
Subject: [PATCH] replaced Logstash initscript with one tailored for
 Logstash-forwarder

---
 .../etc/init.d/logstashforwarder.Debian.erb   | 316 ++++++++----------
 1 file changed, 136 insertions(+), 180 deletions(-)

diff --git a/templates/etc/init.d/logstashforwarder.Debian.erb b/templates/etc/init.d/logstashforwarder.Debian.erb
index 210d761..22c9a31 100644
--- a/templates/etc/init.d/logstashforwarder.Debian.erb
+++ b/templates/etc/init.d/logstashforwarder.Debian.erb
@@ -1,203 +1,159 @@
-#!/bin/bash
-#
-# /etc/init.d/logstash -- startup script for LogStash.
+#!/bin/sh
+# Init script for logstash-forwarder
+# Maintained by @poolski
+# Generated by pleaserun.
+# Implemented based on LSB Core 3.1:
+#   * Sections: 20.2, 20.3
 #
 ### BEGIN INIT INFO
-# Provides:          logstash
-# Required-Start:    $all
-# Required-Stop:     $all
+# Provides:          logstash-forwarder
+# Required-Start:    $remote_fs $syslog
+# Required-Stop:     $remote_fs $syslog
 # Default-Start:     2 3 4 5
 # Default-Stop:      0 1 6
-# Short-Description: Starts logstash
-# Description:       Starts logstash using start-stop-daemon
+# Short-Description: 
+# Description:       Logstash event forwarder
 ### END INIT INFO
 
-set -e
-
-PATH=/bin:/usr/bin:/sbin:/usr/sbin
-NAME=logstash
-DESC="Logstash Daemon"
-DEFAULT=/etc/default/$NAME
-
-if [ `id -u` -ne 0 ]; then
-   echo "You need root privileges to run this script"
-   exit 1
-fi
-
-. /lib/lsb/init-functions
-
-if [ -r /etc/default/rcS ]; then
-   . /etc/default/rcS
-fi
-
-# The following variables can be overwritten in $DEFAULT
-
-# Run logstash as this user ID and group ID
-LS_USER=logstash
-LS_GROUP=logstash
-
-JAVA=/usr/bin/java
-
-# Directory where the logstash all in one jar lives
-LS_HOME=/var/lib/logstash
-
-# Additional Java OPTS
-LS_JAVA_OPTS=" -Djava.io.tmpdir=/var/logstash/"
-
-# logstash log directory
-LOG_DIR=/var/log/logstash
+PATH=/sbin:/usr/sbin:/bin:/usr/bin
+export PATH
+
+name=logstash-forwarder
+program=/opt/logstash-forwarder/bin/logstash-forwarder
+# Runtime arguments
+# Tune -spool-size to get optimum performance. Beware of setting it too high
+# or your nodes will overwhelm your indexer/relay with events as they'll send
+# N events per batch, where N is -spool-size.
+args='-config /etc/logstash-forwarder.conf -log-to-syslog -spool-size 100'
+pidfile="/var/run/$name.pid"
+
+# Load environment variables
+user="root"
+group="root"
+chroot="/"
+chdir="/"
+nice=""
+
+trace() {
+  logger -t "/etc/init.d/logstash-forwarder" "$@"
+}
 
-# logstash configuration directory
-CONF_DIR=/etc/logstash/conf.d
+emit() {
+  trace "$@"
+  echo "$@"
+}
 
-# logstash log file
-LOG_FILE=$LOG_DIR/$NAME.log
+start() {
 
-# Open File limit
-OPEN_FILES=2048
 
-# LogStash options
-LS_OPTS="--log ${LOG_DIR}/${NAME}.log"
+  # Setup any environmental stuff beforehand
+  
 
-# Nice level
-NICE=19
+  # Run the program!
+  
+  chroot --userspec "$user":"$group" "$chroot" sh -c "
+    
+    cd \"$chdir\"
+    exec \"$program\" $args
+  " > /var/log/$name.log 2> /var/log/$name.err &
 
-# End of variables that can be overwritten in $DEFAULT
+  # Generate the pidfile from here. If we instead made the forked process
+  # generate it there will be a race condition between the pidfile writing
+  # and a process possibly asking for status.
+  echo $! > $pidfile
 
-# overwrite settings from default file
-if [ -f "$DEFAULT" ]; then
-   . "$DEFAULT"
-fi
+  emit "$name started"
+  return 0
+}
 
-# Define other required variables
-PID_FILE=/var/run/$NAME.pid
-DAEMON=$LS_JAR
-DAEMON_OPTS="agent -f ${CONF_DIR} ${LS_OPTS}"
+stop() {
+  # Try a few times to kill TERM the program
+  if status ; then
+    pid=$(cat "$pidfile")
+    trace "Killing $name (pid $pid) with SIGTERM"
+    kill -TERM $pid
+    # Wait for it to exit.
+    for i in 1 2 3 4 5 ; do
+      trace "Waiting $name (pid $pid) to die..."
+      status || break
+      sleep 1
+    done
+    if status ; then
+      emit "$name stop failed; still running."
+    else
+      emit "$name stopped."
+    fi
+  fi
+}
 
-is_true() {
-    if [ "x$1" = "xtrue" -o "x$1" = "xyes" -o "x$1" = "x1" ] ; then
-        return 0
+status() {
+  if [ -f "$pidfile" ] ; then
+    pid=$(cat "$pidfile")
+    if ps -p $pid > /dev/null 2> /dev/null ; then
+      # process by this pid is running.
+      # It may not be our pid, but that's what you get with just pidfiles.
+      # TODO(sissel): Check if this process seems to be the same as the one we
+      # expect. It'd be nice to use flock here, but flock uses fork, not exec,
+      # so it makes it quite awkward to use in this case.
+      return 0
     else
-        return 1
+      return 2 # program is dead but pid file exists
     fi
+  else
+    return 3 # program is not running
+  fi
+}
+
+force_stop() {
+  if status ; then
+    stop
+    status && kill -KILL $(cat "$pidfile")
+  fi
 }
 
-# Check DAEMON exists
-if ! test -e $DAEMON; then
-   log_failure_msg "Daemon $DAEMON doesn't exist"
-   exit 1
-fi
 
 case "$1" in
-   start)
-      if ! is_true "$START" ; then
-         echo "logstash not configured to start, please edit /etc/default/logstash to enable"
-         exit 0
-      fi
-
-      if [ -z "$JAVA" ]; then
-         log_failure_msg "no JDK found - $JAVA"
-         exit 1
-      fi
-
-      # Check if a config file exists
-      if [ ! "$(ls -A $CONF_DIR/*.conf 2> /dev/null)" ]; then
-         log_failure_msg "There aren't any configuration files in $CONF_DIR"
-         exit 1
-      fi
-
-      log_daemon_msg "Starting $DESC"
-
-      if start-stop-daemon --test --start --pidfile "$PID_FILE" \
-         --user "$LS_USER" --exec "$JAVA" \
-      >/dev/null; then
-         # Prepare environment
-         ulimit -n $OPEN_FILES
-
-         # Start Daemon
-         start-stop-daemon --start -b --user "$LS_USER" -c "$LS_USER":"$LS_GROUP" \
-           -d "$LS_HOME" --pidfile "$PID_FILE" --make-pidfile \
-           -N $NICE \
-           --exec "$JAVA" -- $LS_JAVA_OPTS -jar $DAEMON $DAEMON_OPTS
-
-         sleep 1
-
-         if start-stop-daemon --test --start --pidfile "$PID_FILE" \
-            --user "$LS_USER" --exec "$JAVA" \
-         >/dev/null; then
-
-            if [ -f "$PID_FILE" ]; then
-               rm -f "$PID_FILE"
-            fi
-
-            log_end_msg 1
-         else
-            log_end_msg 0
-         fi
-      else
-         log_progress_msg "(already running)"
-         log_end_msg 0
-      fi
-   ;;
-   stop)
-      log_daemon_msg "Stopping $DESC"
-
-      set +e
-
-      if [ -f "$PID_FILE" ]; then
-         start-stop-daemon --stop --pidfile "$PID_FILE" \
-            --user "$LS_USER" \
-            --retry=TERM/20/KILL/5 >/dev/null
-
-         if [ $? -eq 1 ]; then
-            log_progress_msg "$DESC is not running but pid file exists, cleaning up"
-         elif [ $? -eq 3 ]; then
-            PID="`cat $PID_FILE`"
-            log_failure_msg "Failed to stop $DESC (pid $PID)"
-            exit 1
-         fi
-
-         rm -f "$PID_FILE"
-      else
-         log_progress_msg "(not running)"
-      fi
-
-      log_end_msg 0
-      set -e
-   ;;
-   status)
-      set +e
-
-      start-stop-daemon --test --start --pidfile "$PID_FILE" \
-         --user "$LS_USER" --exec "$JAVA" \
-      >/dev/null 2>&1
-
-      if [ "$?" = "0" ]; then
-         if [ -f "$PID_FILE" ]; then
-            log_success_msg "$DESC is not running, but pid file exists."
-            exit 1
-         else
-            log_success_msg "$DESC is not running."
-            exit 3
-         fi
-      else
-         log_success_msg "$DESC is running with pid `cat $PID_FILE`"
-      fi
-
-      set -e
-   ;;
-   restart|force-reload)
-      if [ -f "$PID_FILE" ]; then
-         $0 stop
-         sleep 1
-      fi
-
-      $0 start
-   ;;
-   *)
-      log_success_msg "Usage: $0 {start|stop|restart|force-reload|status}"
-      exit 1
-   ;;
+  force-start|start|stop|force-stop|restart)
+    trace "Attempting '$1' on logstash-forwarder"
+    ;;
+esac
+
+case "$1" in
+  force-start)
+    PRESTART=no
+    exec "$0" start
+    ;;
+  start)
+    status
+    code=$?
+    if [ $code -eq 0 ]; then
+      emit "$name is already running"
+      exit $code
+    else
+      start
+      exit $?
+    fi
+    ;;
+  stop) stop ;;
+  force-stop) force_stop ;;
+  status) 
+    status
+    code=$?
+    if [ $code -eq 0 ] ; then
+      emit "$name is running"
+    else
+      emit "$name is not running"
+    fi
+    exit $code
+    ;;
+  restart) 
+    
+    stop && start 
+    ;;
+  *)
+    echo "Usage: $SCRIPTNAME {start|force-start|stop|force-start|force-stop|status|restart}" >&2
+    exit 3
+  ;;
 esac
 
-exit 0
+exit $?