#!/bin/bash
#
# health-report2.sh [-tdm email] [-c] [-r YYYY-MM-DD email]
#  - Simple reporting tool to email top, df and memory reports
#  - Supports collect only mode for aggregation
#
# Changelog:
#  * 2014-05-22 - Nathan Isburgh <nathan@edgecloud.com>
#               - Initial version of script
#

# Debug flag - 1 for verbose debugging
DEBUG=1

#
# NO EDITS BELOW THIS LINE
#

#
# succeed()
#  - gracefully exit from program successfully
#
succeed() {
  cleanup
  exit 0
}

#
# fail( code, msg )
#  - gracefully exit from program in failure state
#
fail() {
  cleanup
  if [ -n "$2" ]
  then
    echo "$2" > /dev/stderr
  fi
  exit ${1:-1}
}

#
# cleanup()
#  - clean up log/lock files, etc
#
cleanup() {
  rm -f $TEMPFILE
  return
}

#
# debug( msg )
#  - Prints standard debug message to stderr
#  - Only print if debugging is enabled
#
debug() {
  if [ "$DEBUG" -ne 1 ]
  then
    return
  fi
  echo $(date +%T) " $@" > /dev/stderr
}

#
# usage()
#  - Print a basic usage statement for user to understand program use
#
usage() {
  cat << eof
Usage:
    $0 [-tdm email] [-c] [-r YYYY-MM-DD email]
   Sends requested reports to the given email address
 -t        Send a top report
 -d        Send a df report
 -m        Send a memory report
 -c        Collect only mode, logging to /tmp
 -r        Report mode, email requested log to supplied address
 email     Email recipient for the generated reports
eof
}

#
# topreport()
#  - Sends an email of the top command output to $EMAIL
#
topreport() {
  reportheader "Top Report"
  top -bn 1
}

#
# dfreport()
#  - Sends an email of the df command output to $EMAIL
#
dfreport() {
  reportheader "df Report"
  df -h
}

#
# memreport()
#  - Sends an email of memory usage to $EMAIL
#
memreport() {
  reportheader "Memory Report"
  ps -Ao comm= -o %mem= | sort -nrk 2
}

#
# reportheader(header)
#  - spit out a basic report header
#
reportheader() {
  printf '******************************************************\n'
  printf '* %-12s %-37s *\n' $(date +%T) "$1"
  printf '******************************************************\n'
}

# Main code body
# ...

TOPREPORT=0
DFREPORT=0
MEMREPORT=0
COLLECT=0
REPORT=0

while getopts ":tdmcr:" opt; do
  case $opt in
    t)
      debug "top report requested"
      TOPREPORT=1
      ;;
    d)
      debug "df report requested"
      DFREPORT=1
      ;;
    m)
      debug "mem report requested"
      MEMREPORT=1
      ;;
    c)
      debug "collect mode requested"
      COLLECT=1
      ;;
    r)
      debug "report mode requested"
      REPORT=1
      REPORTDATE=$(date -d "$OPTARG" +%F 2>&1)
      if [ $? -ne 0 ]
      then
        usage
        fail 10 "$REPORTDATE"
      fi
      ;;
    \?)
      usage
      fail 1 "Invalid option: -$OPTARG"
      ;;
    :)
      usage
      fail 2 "Option -$OPTARG requires an argument."
      ;;
  esac
done

eval EMAIL=\${$OPTIND}
 # After processing the above command line, the resulting command
 # line becomes:
 #  eval EMAIL=${8}
debug "\$#: $# \$OPTIND: $OPTIND \$EMAIL: '$EMAIL'"

# Make sure the user supplied an email address ( not in collect mode )
if [ "$COLLECT" -eq 0 -a -z "$EMAIL" ]
then
  usage
  fail 3 "Please supply an email address for the reports"
fi

TEMPFILE=$(mktemp)

# This code block actually runs/aggregates all of the reports
# in to the TEMPFILE
(
  if [ "$TOPREPORT" -eq 1 ]
  then
    topreport
  fi
  if [ "$DFREPORT" -eq 1 ]
  then
    dfreport
  fi
  if [ "$MEMREPORT" -eq 1 ]
  then
    memreport
  fi
) > $TEMPFILE

if [ "$COLLECT" -eq 1 ]
then
  cat $TEMPFILE >> /tmp/health-report.$(date +%F)
else
  if [ "$REPORT" -eq 1 ]
  then
    if [ -e /tmp/health-report.$REPORTDATE ]
    then
      mailx -s "Health reports for $REPORTDATE" $EMAIL < /tmp/health-report.$REPORTDATE
    else
      usage
      fail 20 "No information available for requested date ( $REPORTDATE )"
    fi
  else
    mailx -s "Health reports" $EMAIL < $TEMPFILE
  fi
fi

succeed