#!/bin/bash


##################################################################################################
# log_search                                                                                     #
##################################################################################################
# This utility was made to make searching for logs much quicker on both a redbox (journal) & on  #
# the logserver (via messages files).                                                            #
#                                                                                                #
#                                                                                                #
#                                                                                                #
#                                                                                                #
##################################################################################################


# BEGIN: Variables

declare -A CONFIG
CONFIG[source]=""
CONFIG[mode]=""
CONFIG[regex]=""
CONFIG[service_search]=0
CONFIG[last_nth_days]=1
CONFIG[hostname]="N/A"
CONFIG[service_filter]="N/A"

declare -A SEARCH_MODES=(
  ['CLUSTER']='(crmd|stonith|pengine|lrmd|pacemakerd|corosync|drbd)\['
  ['ISSUES']='warn|crit|fail|err'
)

# END: Variables



# BEGIN: Helper Functions

usage () {
  cat <<EOF
$( basename $0 ) [-s|--source <source>] [-m|--mode <mode>] [--services] [-l|--last-nth-days <int>] [-H|--hostname <hostname>]

Sources:
  log                      : When used on the log-server for a customer environment (references the hosts messages file /var/log/hosts/<hostname>/YYYY/MM/DD/messages*)
  journal                  : When used on a node (referenced a nodes journal for finding errors)

Search Modes
  cluster                  : Searching for errors that are cluster related (matches regex: ${SEARCH_MODES[CLUSTER]})
  issues                   : General issues that report a warning, failure, error,  critical, etc (matches regex: ${SEARCH_MODES[ISSUES]})

Flags:
  Universal:
    --services               : Get all the service names that return from the search
    --filter-regex <regex>    : Will be used to filter only the services you want to 
  Log Source:
    -l|--last-nth-days <int> : (only used with log source) Search for logs in the last nth days.
    -H|--hostname <hostname> : Hostname to search against
EOF
}

# END: Helper Functions


# BEGIN: Handle CLI Args

if [[ $# -eq 0 ]]; then
	usage
	exit
fi

while [[ $# -ne 0 ]]; do
  case $1 in
	  -s | --source )
		  if [[ "$2" != "" ]] && [[ "${2,,}" =~ ^(log|journal)$ ]]; then
			  case ${2,,} in
				  log) CONFIG[source]="log";;
				  journal) CONFIG[source]='journal';;
			  esac
			  shift
			  continue
		  else
			  echo "$2 is not a valid option for $1"
			  usage
			  exit
		  fi
	  ;;

	  -m | --mode)
		  if [[ "$2" != "" ]] && [[ "${2,,}" =~ ^(issues|cluster)$ ]]; then
		    case ${2,,} in
		      issues) 
			      CONFIG[mode]="issues"
			      CONFIG[regex]=${SEARCH_MODES[ISSUES]}
			      ;;
		      cluster) 
			      CONFIG[mode]='cluster'
			      CONFIG[regex]=${SEARCH_MODES[CLUSTER]}
			      ;;
	  	    esac
			shift
			continue
		  else
			  echo "$2 is not a valid option for $1"
			  usage
			  exit
		  fi
	  ;;

	  --services)
		  CONFIG[service_search]=1
	  ;;

	  -H | --hostname )
		  if [[ "$2" != "" ]] ; then
			  LOG_PATH=/var/log/hosts/$2
			  if [[ -d $LOG_PATH ]]; then
				  CONFIG[hostname]=$2
			  else
				  echo "$LOG_PATH does not exist. Either the host doesn't exist or hasn't logged to this server"
				  usage
				  exit
			  fi
		  fi
	  ;;

  esac
  shift
done

# END: Handle CLI Args



# BEGIN: Pre-Work Checks

for KEY in ${!CONFIG[@]}; do
	if [[ "${CONFIG[$KEY]}" == "" ]]; then
		echo "$KEY was not set"
		exit
	fi
done

case ${CONFIG[mode]} in
	log)
		if [[ ${CONFIG[hostname]} == "N/A" ]]; then
			echo "A hostname was not provieded (via -H|--hostname), and it is required to do a log search"
			usage
			exit
		fi
		;;
esac

# END: Pre-Work Checks




# BEGIN: Work Functions

gather_logs_from_journal () {
	local -n OUTPUT_VAR=${1:?"$FUNCNAME: Output Variable not provided"}
	OUTPUT_VAR=$( sudo journalctl --no-pager | grep -E ${CONFIG[regex]} )
}

gather_logs_from_files () {
	shopt -s globstar
	local -a FILES=( $( ls -1r /var/log/hosts/${CONIFG[hostname]}/**/messages* ) )
	local -n OUTPUT_VAR=${1:?"$FUNCNAME: Output Variable not provided"}
	local OUTPUT BUFFER

	local FILE
	for FILE in ${FILES[@]:0:${CONFIG[last_nth_days]}}; do 
		BUFFER=$( zgrep -E "${CONFIG[regex]}" $FILE )
		OUTPUT="$OUTPUT\n$BUFFER"
	done
	OUTPUT_VAR=$( echo -e "$OUTPUT" ) 
}

# END: Work Functions


# BEGIN: Work

OUTPUT=""

case ${CONFIG[source]} in
	log) gather_logs_from_files OUTPUT;;
	journal) gather_logs_from_journal OUTPUT;;
esac

if [[ ${CONFIG[service_search]} -eq 1 ]]; then
	echo "$OUTPUT" | awk '{ print $5 }' | cut -d '[' -f 1 | sort -u
elif [[ ${CONFIG[service_filter]} != "N/A" ]]; then
	echo "$OUTPUT" | grep -E "${CONFIG[service_filter]}"
else
	echo "$OUTPUT"
fi

# END: Work