Logging helpers for shell

logging.sh

##### Logging Setup #####
# NOTE this code piece taken from: https://gist.github.com/goodmami/6556701
exec 3>&2 # logging stream (file descriptor 3) defaults to STDERR

_trc_lvl=0
_crt_lvl=1
_err_lvl=2
_wrn_lvl=3
_inf_lvl=4
_dbg_lvl=5
_lvl_str_list=(TRACE CRITICAL ERROR WARNING INFO DEBUG)
LOGGING_VERBOSITY=$_dbg_lvl

function _log_it() {
  local log_lvl
  log_lvl=$1

  if [ "$LOGGING_VERBOSITY" -ge "$log_lvl" ]; then
    local date_string
    local level_str
    date_string=$(date +'%Y-%m-%d %H:%M:%S')
    level_str="${_lvl_str_list[$log_lvl]}"
    echo -e "[$date_string] [$level_str] - $2" >&3
  fi
}

function log_critical() {
  _log_it "$_crt_lvl" "$1"
}

function log_error() {
  _log_it "$_err_lvl" "$1"
}

function log_warning() {
  _log_it "$_wrn_lvl" "$1"
}

function log_info() {
  _log_it "$_inf_lvl" "$1"
}

function log_debug() {
  _log_it "$_dbg_lvl" "$1"
}

function log_trace() {
  _log_it "$_trc_lvl" "$1"
}
##### Logging Setup #####