tail 显示INFO ERROR WARN DEBUG 的颜色

保存成 ctail , 使用 命令 ctail -f xxx.log

#!/usr/bin/env bash

###############################################################################
# Author: Radu Cotescu <radu@cotescu.com>                                     #
#                                                                             #
# ctail is a small configurable Bash script which can colour log entries      #
# outputted through tail. It actually wraps tail, piping its output through   #
# an awk script that colorizes the output according to log severity levels.   #
###############################################################################

if ! TAIL="$(which tail)"; then
echo -e "Cannot find tail executable.\n"
exit 1
fi

if ! AWK="$(which awk)"; then
echo -e "Cannot find awk executable.\n"
exit 1
fi

awk_opts=()
# detect if awk is mawk (which is common on debian based distros)
case "$(realpath "$AWK")" in
*/mawk)
awk_opts+=(-W interactive)
;;
esac

declare -A log
log["INFO"]="BWhite"
log["信息"]="BWhite"
log["ERROR"]="BRed"
log["严重"]="BRed"
log["WARN"]="BYellow"
log["警告"]="BYellow"
log["DEBUG"]="BGreen"

# log["INFO"]="BWhite"
# log["ERROR"]="BRed"
# log["WARN"]="BYellow"
# log["DEBUG"]="BGreen"

# keep original behaviour; hide lines that does not match any of the pattern
: "${print_lines_not_matched:=1}"

# keeping the original behaviour; load config from the ctail script's directory
CWD="$(dirname "$0")"
if [[ -f "$CWD/ctail.config" ]]; then
# shellcheck disable=SC1090
source "$CWD/ctail.config"
fi

# if there is a config in $HOME, load that
if [[ -f "$HOME/ctail.config" ]]; then
# shellcheck disable=SC1090
source "$HOME/ctail.config"
fi

# if there is a config in current directory, load that too
if [[ -f "./ctail.config" ]]; then
source "./ctail.config"
fi

declare -A colours
# Regular
colours["Black"]="\033[0;30m"
colours["Red"]="\033[0;31m"
colours["Green"]="\033[0;32m"
colours["Yellow"]="\033[0;33m"
colours["Blue"]="\033[0;34m"
colours["Purple"]="\033[0;35m"
colours["Cyan"]="\033[0;36m"
colours["White"]="\033[0;37m"
#Bold
colours["BBlack"]="\033[1;30m"
colours["BRed"]="\033[1;31m"
colours["BGreen"]="\033[1;32m"
colours["BYellow"]="\033[1;33m"
colours["BBlue"]="\033[1;34m"
colours["BPurple"]="\033[1;35m"
colours["BCyan"]="\033[1;36m"
colours["BWhite"]="\033[1;37m"
# High Intensity
colours["IBlack"]="\033[0;90m"
colours["IRed"]="\033[0;91m"
colours["IGreen"]="\033[0;92m"
colours["IYellow"]="\033[0;93m"
colours["IBlue"]="\033[0;94m"
colours["IPurple"]="\033[0;95m"
colours["ICyan"]="\033[0;96m"
colours["IWhite"]="\033[0;97m"
# Bold High Intensity
colours["BIBlack"]="\033[1;90m"
colours["BIRed"]="\033[1;91m"
colours["BIGreen"]="\033[1;92m"
colours["BIYellow"]="\033[1;93m"
colours["BIBlue"]="\033[1;94m"
colours["BIPurple"]="\033[1;95m"
colours["BICyan"]="\033[1;96m"
colours["BIWhite"]="\033[1;97m"

awk_script() {
for i in "${!log[@]}"; do
echo "/$i/ {print \"${colours[${log[$i]}]}\" \$0 \"\033[39m\"; next;}"
done

if [[ "$print_lines_not_matched" == "1" ]]; then
# let us not miss anything that did not match any of the above colourisation rules
# shellcheck disable=SC2016
echo "{print \"${colours["Yellow"]}\" \$0 \"\033[39m\"}"
# echo '{print $0}'
fi
}

if [ -t 0 ]; then
$AWK "${awk_opts[@]}" -f <(awk_script) < <($TAIL "$@")
else
$AWK "${awk_opts[@]}" -f <(awk_script)
fi