Script to run only in the specified minute range

clock

#!/usr/bin/env bash

# Created by Benjamin Fleischer 2019
# Distributed under the MIT license
# 
# Usage:
#  MINUTE_RANGES="0...10 30...40" ./clock echo 'we done it'
#  DEBUG=true MINUTE_RANGES="0...10 30...40" ./clock echo 'we done it'
main() {
  local ranges
  if [ ${#MINUTE_RANGES[@]} -eq 0 ]; then
    echo "MINUTE_RANGES not set. See USAGE. Not Executing: $@" >&2
    exit 1
  else
    ranges=( $MINUTE_RANGES )
  fi
  local range_number
  range_number=0
  local number_of_ranges
  number_of_ranges=${#ranges[@]}
  local current_min="$(date +"%M")"
  local ruby_condition
  ruby_condition="min = '${current_min}'.to_i; exit ("
  for range in ${ranges[*]} ; do
    range_number=$(( range_number+1 ))
    ruby_condition="${ruby_condition} (${range}).cover?(min)"
    if [ $range_number -lt $number_of_ranges ]; then
      ruby_condition="${ruby_condition} || "
    fi
  done
  ruby_condition="${ruby_condition} )"
  if [ ! -z "${DEBUG:-}" ]; then
    echo "ruby_condition: ${ruby_condition}"
  fi
  if ruby -e "${ruby_condition}"; then
    echo "ranges=[${ranges[*]}] current_min=${current_min} Executing: $@"
    exec $@
  else
    echo "ranges=[${ranges[*]}] current_min=${current_min} NOT Executing: $@"
    true
  fi
}

main $@