Install Google Chrome on a Debian-based system.

google.chrome.install.sh

##/bin/bash
## Install Google Chrome on a Debian-based system.
## By Stephen D. Rogers <inbox.c7r@steve-rogers.com>, 2018-02.
##
## Typical uses:
##
##     google.chrome.install.sh
##     google.chrome.install.sh --stable # latest stable version
##     
##     google.chrome.install.sh --lkg    # last known good version
## 

set -e

umask 0002

##

function install_google_chrome__stable() {

	wget -q -O - https://dl-ssl.google.com/linux/linux_signing_key.pub | sudo apt-key add -

	echo "deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable main" |
	sudo cp /dev/stdin /etc/apt/sources.list.d/google-chrome.list

	sudo apt install google-chrome-stable
}

function install_google_chrome__lkg() {

	local lkg_id=20180103111537

	local google_chrome_deb_url="https://web.archive.org/web/${lkg_id}if_/" # LKG version for Ubuntu 14.04 (libnss 2:3.15.4-1ubuntu7).
	google_chrome_deb_url="${google_chrome_deb_url}https://dl.google.com/linux/direct/google-chrome-stable_current_amd64.deb"

	local google_chrome_deb_fpn="${HOME}/Downloads/${google_chrome_deb_url##*/}"
	google_chrome_deb_fpn="${google_chrome_deb_fpn%.deb}--${lkg_id}.deb"

	if ! [ -e "${google_chrome_deb_fpn:?}" ] ; then

		xx wget -q -O "${google_chrome_deb_fpn:?}" "${google_chrome_deb_url:?}"

		echo "${google_chrome_deb_url:?}" > "${google_chrome_deb_fpn:?}".url
	fi

	! false ||
	xx sudo apt install libnss3 # prerequisite for chrome

	xx sudo dpkg --install "${google_chrome_deb_fpn:?}"
}

function main() { # ...

	local variant

	case "$1" in
	--lkg)
		variant=lkg ; shift
		;;
	--stable|'')
		variant=stable ; shift
		;;
	*)
		echo 1>&2 "Unrecognized option: $1" ; exit 2
		;;
	esac

	install_google_chrome__${variant} "$@"
}

##

main "$@"