utils.sh

#!/bin/bash

# Sometime it is better to explicitly define an UNSET value for variables
UNSET="UNSET"


###################################################################################################
# COLOR DEFINITION
###################################################################################################

# Reset color
RCol='\e[0m'

# Regular           Bold                Underline           High Intensity      BoldHigh Intens     Background          High Intensity Backgrounds
Bla='\e[0;30m';     BBla='\e[1;30m';    UBla='\e[4;30m';    IBla='\e[0;90m';    BIBla='\e[1;90m';   On_Bla='\e[40m';    On_IBla='\e[0;100m';
Red='\e[0;31m';     BRed='\e[1;31m';    URed='\e[4;31m';    IRed='\e[0;91m';    BIRed='\e[1;91m';   On_Red='\e[41m';    On_IRed='\e[0;101m';
Gre='\e[0;32m';     BGre='\e[1;32m';    UGre='\e[4;32m';    IGre='\e[0;92m';    BIGre='\e[1;92m';   On_Gre='\e[42m';    On_IGre='\e[0;102m';
Yel='\e[0;33m';     BYel='\e[1;33m';    UYel='\e[4;33m';    IYel='\e[0;93m';    BIYel='\e[1;93m';   On_Yel='\e[43m';    On_IYel='\e[0;103m';
Blu='\e[0;34m';     BBlu='\e[1;34m';    UBlu='\e[4;34m';    IBlu='\e[0;94m';    BIBlu='\e[1;94m';   On_Blu='\e[44m';    On_IBlu='\e[0;104m';
Pur='\e[0;35m';     BPur='\e[1;35m';    UPur='\e[4;35m';    IPur='\e[0;95m';    BIPur='\e[1;95m';   On_Pur='\e[45m';    On_IPur='\e[0;105m';
Cya='\e[0;36m';     BCya='\e[1;36m';    UCya='\e[4;36m';    ICya='\e[0;96m';    BICya='\e[1;96m';   On_Cya='\e[46m';    On_ICya='\e[0;106m';
Whi='\e[0;37m';     BWhi='\e[1;37m';    UWhi='\e[4;37m';    IWhi='\e[0;97m';    BIWhi='\e[1;97m';   On_Whi='\e[47m';    On_IWhi='\e[0;107m';


###################################################################################################
# NICE UNICODE CHARACTER (WITH COLOR)
###################################################################################################
check="${BGre}\U1d00c${RCol} "
cross="${BRed}\Ud7${RCol} "
star="${Cya}\U2605${RCol} "
warn="${BYel}\U26a0${RCol} "


###################################################################################################
# GENERIC ECHO FUNCTIONS
###################################################################################################

# Display usage it no argument
usageIfNoArgument() {
  if [[ ${#} -eq 0 ]]; then
    usage
  fi
}

# Exit script with the given code, do nothing if no argument
exitIfCodeNotEmpty() {
  local exitCode=${1}

  if [[ "${exitCode}" != "" ]]; then
     exit ${exitCode}
  fi
}

# Display an error message (on STDERR) and exit the script if an exitCode has been given
error() {
  local exitMessage=${1}
  local exitCode=${2}

  >&2 echo -e ${Red}${exitMessage}${RCol}
  exitIfCodeNotEmpty ${exitCode}
}

# Echo starting with a green check
check() {
  echo -e " ${check} ${1}"
}

# Echo starting with a red cross
fail() {
  echo -e " ${cross} ${1}"
}

# Echo starting with a warn yellow icon
warn() {
  echo -e " ${warn} ${1}"
}

# Colored echo message
info() {
  echo -e "${Cya}${1}${RCol}"
}

# Advanced echo with a type in argument (check, warn, etc)
xecho() {
  local message=${1}
  local echoType=${2}

  case ${echoType} in
    check)
      check ${message};;
    fail)
      fail ${message};;
    warn)
      warn ${message};;
    info)
      info ${message};;
    *)
      echo ${message};;
  esac
}


# Colored Echo starting with a star
command() {
  echo -e " ${star} ${BWhi}COMMAND: ${1}${RCol}"
}


###################################################################################################
# GENERIC SCRIPT FUNCTIONS
###################################################################################################

# Return the absolute path of this script (manage symbolic links)
getScriptDirectory() {
  local source="${BASH_SOURCE[0]}"
  local dir
  # resolve source until the file is no longer a symlink
  while [ -h "${source}" ]; do
    dir="$( cd -P "$( dirname "${source}" )" && pwd )"
    source="$(readlink "${source}")"
    # if source was a relative symlink, we need to resolve it relative to the path where the symlink file was located
    [[ ${source} != /* ]] && source="${dir}/${source}"
  done
  dir="$( cd -P "$( dirname "${source}" )" && pwd )"
  echo "${dir}"
}

# Return 0 and write a check echo if the directory exists. If not, echo a fail or warn message depending the
# second argument and, if an exit code is set, exit, return 1 otherwise.
verifyDirectoryExists() {
  local path=${1}
  local echoFailType=${2}
  local exitCode=${3}
  local returnCode=0

  if [ -d "${path}" ]; then
    check "Directory '${path}' exists"
  else
    xecho "Directory '${path}' doesn't exist" ${echoFailType}
    returnCode=1
  fi
  exitIfCodeNotEmpty ${exitCode}
  return returnCode
}

# Return 0 and write a check echo if the file exists. If not, echo a fail or warn message depending the
# second argument and, if an exit code is set, exit, return 1 otherwise.
verifyFileExists() {
  local path=${1}
  local echoFailType=${2}
  local exitCode=${3}
  local returnCode=0

  if [ -f "${path}" ]; then
    check "File '${path}' exists"
  else
    xecho "File '${path}' doesn't exist" ${echoFailType}
    returnCode=1
  fi
  exitIfCodeNotEmpty ${exitCode}
  return returnCode
}

# Return 0 and write a check echo if the user exists. If not, echo a fail or warn message depending the
# second argument and, if an exit code is set, exit, return 1 otherwise.
verifyUserExists() {
  local user=${1}
  local echoFailType=${2}
  local exitCode=${3}
  local returnCode=0

  id -u ${user} > /dev/null 2>&1
  if [[ ${?} -eq 0 ]]; then
    check "User '${user}' exists (UID=$(id -u ${user}), GID=$(id -u ${user}))"
  else
    xecho "User '${user}' doesn't exist on this system" ${echoFailType}
    returnCode=1
  fi
  exitIfCodeNotEmpty ${exitCode}
  return returnCode
}

# Return 0 and write a check echo if the image exists. If not, echo a fail or warn message depending the
# second argument and, if an exit code is set, exit, return 1 otherwise.
verifyDockerImageExists() {
  local image=${1}
  local echoFailType=${2}
  local exitCode=${3}
  local returnCode=0

  docker images | grep ${image} > /dev/null 2>&1
  if [[ ${?} -eq 0 ]]; then
    check "Docker image '${image}' exists"
  else
    xecho "Docker image '${image}' doesn't exist" ${echoFailType}
    returnCode=1
  fi
  exitIfCodeNotEmpty ${exitCode}
  return returnCode
}