#!/bin/sh
# ------------------------------------------------------------------------
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF 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.
# ------------------------------------------------------------------------
#
## diag.sh - a script to run diagnostic commands and save output to a log file
# 
# Author: Cal Lott <calvin.lott@ihg.com>
#
PATH=$PATH:$HOME/bin:/bin/:/usr/bin:/sbin:/usr/sbin

# Set a script name string for later use.
SCRIPT_NAME=`basename $0`
ORIGINAL_COMMAND_LINE="$0 $*"
LOCALHOST=`uname -n | awk -F. '{print $1}'`

# Declare some functions.

# Prints argument to stdout, prepended with "[YYYYMMDD-HH:MM:SS]".
dateprint() {
  echo "[`date +%Y%m%d-%H:%M:%S`] $*"
}

# Runs argument list as a single shell command.
BAR_SEPARATOR='------------------------------------------------'
run() {
  echo
  echo $BAR_SEPARATOR
  dateprint "START: $*"
  executable=`echo $* | awk '{print $1}'`
  dateprint "path to executable: `which $executable 2>/dev/null`" 
  $*
  last_exit_code=$?
  cumulative_exit_code=`expr $cumulative_exit_code + $last_exit_code`
  dateprint "exit $last_exit_code"
  dateprint "END: $*"
  echo $BAR_SEPARATOR
  echo
}

# Print usage information.
usage() {
  cat << EOF

$SCRIPT_NAME - run a set of standard diagnostic commands

Usage: $SCRIPT_NAME [-l logfile] [-jz] [-hv] <pid1> <pid2> ... <pidN>

This script runs several diagnostic commands on the local system and saves the
output to a gzipped log file. You may also specify an optional list of pids,
which will cause additional diagnostic commands (lsoft, jstat, etc.) to be run
against those specific processes only.

The default path for the datestamped log file is as follows:

  \$HOME/log/$SCRIPT_NAME.\$LOCALHOST.YYYYMMDD-HHMMSS.log

You can override the default file name with the -l option. (See below.)


Options:
-j            Also process any pids listed in output of "jps" command.
-l <logfile>  Use specified log file instead of default.
-z            Do not gzip log file.

Other Options:
-h            Print this message and exit.

EOF
}

# Print help information.
help() {
  usage
}

# Command line options processing.
while getopts "hjl:vz" OPTION
do
  case $OPTION in
    h)
      help
      exit 0
    ;;
    j)
      USE_JPS='TRUE'
    ;;
    l)
      LOGFILE=$OPTARG
    ;;
    z)
      COMPRESSION_OPTION='DISABLED'
    ;;
    ?)
      usage
      exit 1
    ;;
  esac
done
shift `expr $OPTIND - 1` # remove processed arguments from $*
PIDLIST=$*           # save list of remaining args as pidlist

# If requested, use jps to get an additional list of java pids.
if [ "$USE_JPS" = 'TRUE' ]
then
  # Save the current list of pids.
  arg_pids=$PIDLIST
  # Use jps to grab additional java pids, filtering the jps pid itself.
  jps_pids=`jps 2>/dev/null | awk '$2 !~ /^Jps/ {print $1}'`
  # Now obtain an unique sorted list of pids from both groups.
  PIDLIST=`echo $arg_pids $jps_pids | sort | uniq`
fi

# Use the default logfile if the user did not specify one.
if [ "$LOGFILE" = '' ]
then
  LOGFILE="$HOME/log/$SCRIPT_NAME.$LOCALHOST.`date +%Y%m%d-%H%M%S`.log"
fi
# Create log directory if it does not already exist
mkdir `dirname $LOGFILE` >/dev/null 2>&1

# Print start message to stdout.
dateprint "BEGIN - running diagnostics for host: `uname -n`"

# Complain and die if we cannot create the logfile.
touch $LOGFILE >/dev/null 2>&1
if [ $? -eq 0 ]
then
  dateprint "logfile created, running diagnostic commands . . ."
else
  dateprint "ERROR: cannot create $LOGFILE, exiting!"
  exit 1
fi

# Save stdout and stderr descriptors and redirect output to logfile.
exec 6>&1            # Link file descriptor 6 with stdout (saves stdout)
exec 7>&2            # Link file descriptor 7 with stderr (saves stderr)
exec >$LOGFILE 2>&1  # Redirect stdout and stdin to logfile

##
## Begin diagnostic output
##
dateprint "BEGIN DIAGNOSTIC OUTPUT"
dateprint "running on host: `uname -n`"
dateprint "unprocessed command line: \"$ORIGINAL_COMMAND_LINE\""
dateprint "after options processing: \"$0 $PIDLIST > $LOGFILE\""

# Each of the following shell commands will be run once.
for cmd in \
  "crontab -l" \
  "id" \
  "ifconfig -a" \
  "df -kl" \
  "env" \
  "iostat -x" \
  "jps -v" \
  "netstat -anp" \
  "netstat -r" \
  "ps -ef" \
  "sar -A" \
  "ulimit -a" \
  "uname -a" \
  "uptime" \
  "w" \
; do
  run $cmd
done

# As above, but these commands are customized for a specific flavor of Unix.
OS=`uname -s`
case $OS in
  Linux)
    for cmd in \
      "swapon -s" \
      "top -b -n1" \
    ; do
      run $cmd
    done
    ;;
  SunOS)
    for cmd in \
      "swap -s" \
      "top -b -d1" \
    ; do
      run $cmd
    done
  ;;
  *)
    dateprint "WARNING: OS \"$OS\" unknown - running no OS-specific commands"
  ;;
esac

# Each of these commands are run once per each pid argument
for pid in $PIDLIST
do
  for cmd in \
    "lsof -p $pid" \
    "jstat -gcutil $pid" \
    "jstack -l $pid" \
  ; do
    run $cmd
  done
done

dateprint "END DIAGNOSTIC OUTPUT"
dateprint "cumulative exit code: $cumulative_exit_code"

exec 1>&6 6>&-   # Restore stdout and close file descriptor 6.
exec 2>&7 7>&-   # Restore stderr and close file descriptor 7.
##
## End diagnostic output
##

# Compress the logfile if requested and end script execution
if [ "$COMPRESSION_OPTION" = 'DISABLED' ]
then
  dateprint "FINISH - output stored at: $LOGFILE"
else
  nohup gzip $LOGFILE >/dev/null 2>&1 &
  dateprint "FINISH - output stored at: $LOGFILE.gz"
fi

exit $cumulative_exit_code