Bash script that automates upgrading brew packages in a non-admin/admin user setup.

update-brew.sh

#!/bin/bash

###########################################################################
# The following is a workaround for upgrading brew packages when you have
#  separate admin and non-admin users on a macOS device
###########################################################################
# Copyright (c) 2021 Radu Tudorie (rtud)
#
# MIT License
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
###########################################################################

# Edit the following variables with your standard & admin macOS usernames
STANDARD_USER="rtud"
ADMIN_USER="rtud-admin"

BREW_DIR="/usr/local"
TERM=xterm-256color

# Color Defs
F_RESET=$(tput sgr0)
F_BOLD=$(tput bold)
F_RED=$(tput setaf 1)
F_GREEN=$(tput setaf 2)
F_BLUE=$(tput setaf 4)
F_WHITE=$(tput setaf 7)

# Icon Definitions
I_GOOD="${F_BOLD}${F_GREEN}✔${F_RESET}"
I_BAD="${F_BOLD}${F_RED}✖${F_RESET}"
I_INFO="${F_BOLD}${F_BLUE}✻${F_RESET}"
I_TOOLS="${F_BOLD}${F_WHITE}⚒${F_RESET}"


###########################################################################

# To replicate the ASCII art:
#   - visit: http://patorjk.com/software/taag/#p=display&f=ANSI%20Shadow&t=vim
#   - select the "ANSI Shadow" font
echo -e " "
echo -e "${F_WHITE}${F_BOLD} ██████╗ ██████╗ ███████╗██╗    ██╗ ${F_RESET}"
echo -e "${F_WHITE}${F_BOLD} ██╔══██╗██╔══██╗██╔════╝██║    ██║ ${F_RESET}"
echo -e "${F_WHITE}${F_BOLD} ██████╔╝██████╔╝█████╗  ██║ █╗ ██║ ${F_RESET}"
echo -e "${F_WHITE}${F_BOLD} ██╔══██╗██╔══██╗██╔══╝  ██║███╗██║ ${F_RESET}"
echo -e "${F_WHITE}${F_BOLD} ██████╔╝██║  ██║███████╗╚███╔███╔╝ ${F_RESET}"
echo -e "${F_WHITE}${F_BOLD} ╚═════╝ ╚═╝  ╚═╝╚══════╝ ╚══╝╚══╝  ${F_RESET}\n"

if [ "$(whoami)" != "$ADMIN_USER" ]; then
  echo -e "\n${I_BAD}  ${F_WHITE}${F_BOLD}You must run this script as an admin.${F_RESET}"
  echo -e "${I_INFO}  Make sure you've edited the script and configured the ${F_BOLD}STANDARD_USER${F_RESET} and ${F_BOLD}ADMIN_USER${F_RESET} variables as per your macOS setup."
  echo -e "${I_INFO}  To gain access to an admin shell, type ${F_BOLD}su - $ADMIN_USER${F_RESET} in the terminal, then type in the admin password when prompted.\n"

else
  echo -e "${I_TOOLS}  ${F_WHITE}${F_BOLD}Updating the system's brew packages. Please wait...${F_RESET}"
  echo -e "${I_INFO}  The admin user's password might be required to perform the update.\n"

  if [ "$(stat -f "%A" "$BREW_DIR/bin")" != '755' ]; then
    echo -e "${F_WHITE}${F_BOLD}->${F_RESET} Removing group and others permissions on the ${F_BOLD}$BREW_DIR/*${F_RESET}...\n"
    sudo chmod -R g-w,o-w $BREW_DIR/*
  else
    echo -e "${F_WHITE}${F_BOLD}->${F_RESET} Permissions for ${F_BOLD}$BREW_DIR/*${F_RESET} are already setup accordingly.\n"
  fi

  if [ "$(stat -f "%Su" "$BREW_DIR/bin")" != "$ADMIN_USER" ]; then
    echo -e "${F_WHITE}${F_BOLD}->${F_RESET} Temporarily switching ownership for ${F_BOLD}$BREW_DIR/*${F_RESET} to the admin user..."
    sudo chown -R $ADMIN_USER:admin $BREW_DIR/*
  else
    echo -e "${F_WHITE}${F_BOLD}->${F_RESET} Ownweship of ${F_BOLD}$BREW_DIR/*${F_RESET} was already set to the admin user.\n"
  fi

  echo -e "\n${F_WHITE}${F_BOLD}->${F_RESET} Checking in with brew for any updated packages...\n"
  brew update

  echo -e "\n${F_WHITE}${F_BOLD}->${F_RESET} Upgrading the outdated brew pacakages...\n"
  brew upgrade
  
  echo -e "\n${F_WHITE}${F_BOLD}->${F_RESET} Upgrading the outdated brew cask pacakages...\n"
  brew upgrade --cask $(brew list --cask)

  echo -e "\n${F_WHITE}${F_BOLD}->${F_RESET} Switching back ownership for ${F_BOLD}$BREW_DIR/*${F_RESET} to the standard user...\n"
  sudo chown -R $STANDARD_USER:admin $BREW_DIR/*

  echo -e "\n${I_GOOD}  ${F_WHITE}${F_BOLD}Brew packages have been updated.${F_RESET}"
  echo -e "${I_INFO}  Please check the output of brew upgrade and see if there are any manual steps that need running after the update.\n"
fi