Self Updating Github Gist Shellscript

autoupdate.sh

#!/usr/bin/env bash
# -*- coding: utf-8 -*-

set -euo pipefail

# Version 2024/01/28 - Changelog: https://gist.github.com/AriRexouium/4a1277a9e8405a5b357778f6ff0764ba
# This script checks for updates to a GitHub Gist and automatically updates if a new version is available.
#
# Usage: ./autoupdate.sh
#
# License:
#   This script is licensed under the GNU General Public License v3.0 or later.
#   For more information, see https://www.gnu.org/licenses/gpl-3.0.html
#   Copyright (C) 2023 Jarrett Aiken <jarret.aiken@achl.fr> (https://achl.fr)

GITHUB_USERNAME="AriRexouium"; GITHUB_GIST="4a1277a9e8405a5b357778f6ff0764ba"

UPDATE_TIME_FILE="${0}.update"
if [ -f "${UPDATE_TIME_FILE}" ]; then
  UPDATE_TIME=$(cat "${UPDATE_TIME_FILE}")
else
  UPDATE_TIME=0
fi

CURRENT_TIME=$(date +%s); COOLDOWN_TIME=86400
if [ $((CURRENT_TIME - UPDATE_TIME)) -ge ${COOLDOWN_TIME} ]; then
  CURRENT_VERSION=$(cat "${0}"); LATEST_VERSION=$(curl -s https://gist.githubusercontent.com/${GITHUB_USERNAME}/${GITHUB_GIST}/raw)
  if [ "${CURRENT_VERSION}" != "${LATEST_VERSION}" ]; then
    echo "${LATEST_VERSION}" > "${0}"
    chmod +x "${0}"
    echo "${CURRENT_TIME}" > "${UPDATE_TIME_FILE}"
    exec "./${0}" "${@}"
  fi
fi