Bash-script-framework

#!/bin/bash
#===============================================================================
#
#          FILE:  FILENAME.sh
# 
#         USAGE:  ./FILENAME.sh < options >
# 
#  REQUIREMENTS:  ifconfig snmptrap tr sed awk
#        AUTHOR:  Christopher S. Hubbard (), chubbard@iwillfearnoevil.com
#       COMPANY:  I Will Fear No Evil DOT com
#       VERSION:  2.0.1
#       CREATED:  02/18/2011 06:49:51 PM PST
#      REVISION:  Mary
#===============================================================================

Details

Revision starts at the letter A and goes through M

Version starts at 0.0.1 and increments when major changes happen

Requirements are what should be validated before running the script

Use function

usage (){
cat << EOF
Usage: $0 options

Options:
-h  show this help screen
-x  enable debug mode

example:

EOF
}

Verify dependencies

verify_deps() {
# needed="xmllint curl w3m snmptrap cut egrep expr"
needed="snmp_drop_oid.sh grep awk sed"
for i in `echo $needed`
do
  type $i >/dev/null 2>&1
  if [ $? -eq 1 ]; then
    echo "Status WARNING - I am missing mandatory component: $i"; exit 1
  fi
done
}

Logging framework

logger() { if [ ! -e ${canonicaldirname}/logs ];then

 mkdir ${canonicaldirname}/logs

fi

local MESSAGE=${1}

1. "Message" "ERR, or UOW" "Context id"

  if [ -z ${2} ];then
     # If there is no var 2, then this is NOT an error or UOW of some kind.
     local LOGGING="INFO"
     local CONTEXT1=${RANDOM}
  else
     local LOGGING="${2}"
     if [ -z ${3} ];then
        local CONTEXT1=${RANDOM}
     else
        local CONTEXT1="${3}"
     fi
  fi

LOGFILE="${canonicaldirname}/logs/$(date +%F)_someFile.log" touch ${LOGFILE} chmod 664 ${LOGFILE}

local APP_NAME=`echo $0 | awk -F'/' '{print $NF}'`

1. echo "[[\"$(date -u +%FT%H:%M:%S)\", \"Event\", \"\", \"${LOGGING}\", \"`hostname`\", \"${APP_NAME}\", \"$$\", \"0\", \"${CONTEXT1}\", ,\"OPS\", \"${APP_NAME}\"], {\"Event\":\"${MESSAGE}\"}]" >> ${LOGFILE}

echo "\"$(date -u +%FT%H:%M:%S.%3N)\": [[ \"${LOGGING}\", \"$(hostname)\", \"${APP_NAME}\", \"$$\", \"${CONTEXT1}\"], {\"Event\":\"${MESSAGE}\"}]," >> ${LOGFILE} }

1. Begin the log file so JSON is valid

beginlog() { if [ ! -e ${canonicaldirname}/logs ];then

 mkdir ${canonicaldirname}/logs

fi

LOGFILE="${canonicaldirname}/logs/$(date +%F)_someLog.log" touch ${LOGFILE} chmod 664 ${LOGFILE} local DATA=$(tail -1 ${LOGFILE} | wc -m)

1. character count is 2 due to carriage return in output

if [[ ${DATA} -gt 2 ]] ;then

 echo '}' >> ${LOGFILE}

fi } endlog() { if [ ! -e ${canonicaldirname}/logs ];then

 mkdir ${canonicaldirname}/logs

fi

LOGFILE="${canonicaldirname}/logs/$(date +%F)_someLog.log" touch ${LOGFILE} chmod 664 ${LOGFILE} local MESSAGE=${1}

1. "Message" "ERR, or UOW" "Context id"

 if [ -z ${2} ];then
    # If there is no var 2, then this is NOT an error or UOW of some kind.
    local LOGGING="INFO"
    local CONTEXT1=${RANDOM}
 else
    local LOGGING="${2}"
    if [ -z ${3} ];then
       local CONTEXT1=${RANDOM}
    else
       local CONTEXT1="${3}"
    fi
 fi
 echo "\"$(date -u +%FT%H:%M:%S.%3N)\": [[\"${LOGGING}\", \"$(hostname)\", \"${APP_NAME}\", \"$$\", \"${CONTEXT1}\"], {\"Event\":\"${MESSAGE}\"}]" >> ${LOGFILE}
 echo '}' >> ${LOGFILE}

}

Getopts framework

while getopts "hx" OPTION; do
  case ${OPTION} in
    h) usage; exit 0 ;;
    x) export PS4='+(${BASH_SOURCE}:${LINENO}): ${FUNCNAME[0]:+${FUNCNAME[0]}(): }'; set -v ;set -x ;;
    *) echo "Status FATAL - Unexpected arguments given.  Try -h.  Used $@"; exit 2 ;;
  esac
done