timing - script to prefix stdout with the executing time

timing

#!/usr/bin/env bash

# Usage:
# $ command | timing
#
# Example:
# $ rails server | timing
#   00:00:00 | rails server -b 0.0.0.0
#   00:00:04 | => Booting Puma
#   00:00:04 | => Rails 5.1.3 application starting in development on http://0.0.0.0:3000
#   00:00:04 | => Run `rails server -h` for more startup options
#   00:00:04 | [11606] Puma starting in cluster mode...
#   00:00:04 | [11606] * Version 3.10.0 (ruby 2.4.2-p198), codename: Russell's Teapot
#   00:00:04 | [11606] * Min threads: 2, max threads: 4
#   00:00:04 | [11606] * Environment: development
#   00:00:04 | [11606] * Process workers: 3
#   00:00:04 | [11606] * Preloading application
#   00:00:05 | [11606] * Listening on tcp://0.0.0.0:3000

while read -r output; do
  hours=$(($SECONDS / 3600 ))
  minutes=$((($SECONDS % 3600) / 60))
  seconds=$(($SECONDS % 60))

  printf "\033[1;32m%02d:%02d:%02d |\033[00m %s\n" $hours $minutes $seconds "$output"
done