Update (or install) the latest Firefox

firefox-update.sh

#!/usr/bin/env bash
# Update (or install) the latest Firefox
# Optimized for Debian + GNOME
# ffflorian 2017

set -e
SCRIPT_NAME="${0##*/}"

INSTALL_DIR="/opt/firefox"
EXEC_BIN="${INSTALL_DIR}/firefox"
TEMP_DIR="$(mktemp -d)"
ARCHIVE_DIR="${TEMP_DIR}/linux-x86_64/en-US"
SHASUMS_FILE="${TEMP_DIR}/SHA256SUMS"
ICON_FILE="${INSTALL_DIR}/browser/chrome/icons/default/default128.png"
DESKTOP_FILE="/usr/share/applications/firefox.desktop"
ARCHIVE_URL="https://download.mozilla.org/?product=firefox-latest&os=linux64&lang=en-US"
USE_CURL="yes"
FORCE="no"

_cleanup() {
  rm -rf "${TEMP_DIR}"
}

trap _cleanup EXIT

_compare_version() {
  printf "%03d%03d%03d%03d" $(echo "${1}" | tr '.' ' ')
}

_print_usage() {
cat <<EOF
Usage: ${SCRIPT_NAME} [option]

Options:
 --force (-f)       Reinstall Firefox if it is already installed.

Commands:
 --help (-h)        Display this help message
EOF
}

while :
do
  case "${1}" in
    -f|--force )
        FORCE="force"
        shift
        ;;
    -h|--help )
        _print_usage
        exit 0
        ;;
    * )
        break
        ;;
  esac
done

mkdir -p "${ARCHIVE_DIR}"

if [ -d "${INSTALL_DIR}" ]; then
  if [ -r "${EXEC_BIN}" ]; then
    CURRENT_VERSION="$("${EXEC_BIN}" --version | sed -n 's/Mozilla Firefox \(.*\)$/\1/p')"
  else
    read -r -p "The current Firefox installation seems to be broken. Would you like to reinstall the latest version? [y/N] " RESPONSE

    case "${RESPONSE}" in
      [nN][oO]|[nN]|"" ) exit 0 ;;
    esac
    FORCE="force"
  fi
else
  read -r -p "Firefox is not installed yet. Would you like to install it? [y/N] " RESPONSE

  case "${RESPONSE}" in
    [nN][oO]|[nN]|"" ) exit 0 ;;
  esac
  FORCE="force"
fi

if ! command -v "curl" > /dev/null; then
  echo "This script needs curl to run."
  exit 1

  # read -r -p "Info: could not find curl. wget can be used instead but the \
  # Firefox installer hashsum won't be checked then. Would you like to continue? [y/N] " RESPONSE
  # case "${RESPONSE}" in
  #  [nN][oO]|[nN]|"" ) exit 0 ;;
  # esac

  # USE_CURL="no"

  # if ! command -v "wget" > /dev/null; then
  #  echo "Error: could not find curl or wget."
  #  exit 1
  # fi
fi

if [ "${USE_CURL}" = "yes" ]; then
  REDIRECT_URL="$(curl -w "%{url_effective}\\n" -I -L -s -S "${ARCHIVE_URL}" -o /dev/null)"
  ARCHIVE_FILENAME="$(sed -n 's/.*\/en-US\/\(.*\)$/\1/p' <<< "${REDIRECT_URL}")"
  ARCHIVE_FILE="${ARCHIVE_DIR}/${ARCHIVE_FILENAME}"
  BASE_URL="$(sed -n 's/^\(.*\/releases\/[^\/]*\)\/.*/\1/p' <<< "${REDIRECT_URL}")"
  SHASUMS_URL="${BASE_URL}/SHA256SUMS"
  LATEST_VERSION="$(sed -n 's/^.*\/releases\/\([^\/]*\)/\1/p' <<< "${BASE_URL}")"

  if [ "${FORCE}" != "force" ]; then
    if [ "$(_compare_version "${LATEST_VERSION}")" -le "$(_compare_version "${CURRENT_VERSION}")" ]; then
      echo "No update needed, ${CURRENT_VERSION} is the latest Firefox version available."
      echo "Run this script with --force to reinstall this Firefox version."
      exit 0
    fi
  fi

  echo "Downloading Firefox ${LATEST_VERSION} from ${REDIRECT_URL} ... "
  curl -L "${ARCHIVE_URL}" -o "${ARCHIVE_FILE}"
  curl -L "${SHASUMS_URL}" -o "${SHASUMS_FILE}"

  (
    echo "Checking SHA256 hashsum ..."
    cd "${TEMP_DIR}" || exit 1

    sha256sum --quiet --ignore-missing -c "${SHASUMS_FILE}"
  )
else
  echo "This script needs curl to run."
  exit 1
  #echo "Downloading Firefox from ${ARCHIVE_URL} ... "
  #wget -O "${ARCHIVE_FILE}" "${ARCHIVE_URL}"
fi

printf "OK\\n\\n"

if [ ! -r "${ARCHIVE_FILE}" ]; then
  echo "Error: could not find downloaded file \"${ARCHIVE_FILE}\"".
  exit 1
fi

echo "Asking for sudo rights to prepare extraction ... "
sudo mkdir -p "${INSTALL_DIR}"
printf "Extracting Firefox %s to %s ... " "${LATEST_VERSION}" "${INSTALL_DIR}"
sudo tar -xjf "${ARCHIVE_FILE}" --strip-components 1 -C "${INSTALL_DIR}"
printf "OK\\n\\n"

printf "Creating soft link at /usr/bin ... "
sudo ln -fs "${EXEC_BIN}" "/usr/bin/"

printf "OK\\n\\n"

printf "Setting start menu entry ... "

sudo tee "${DESKTOP_FILE}" > /dev/null <<EOF
[Desktop Entry]
Name=Firefox
Comment=Browse the World Wide Web
GenericName=Web Browser
X-GNOME-FullName=Firefox Web Browser
Exec=${EXEC_BIN} %u
Terminal=false
X-MultipleArgs=false
Type=Application
Icon=${ICON_FILE}
Categories=Network;WebBrowser;
MimeType=text/html;text/xml;application/xhtml+xml;application/xml;application/vnd.mozilla.xul+xml;application/rss+xml;application/rdf+xml;image/gif;image/jpeg;image/png;x-scheme-handler/http;x-scheme-handler/https;
StartupWMClass=Firefox
StartupNotify=true
EOF

if [ -r "${ICON_FILE}" ]; then
  printf "OK\\n\\n"
else
  printf "\\Warning: could not find application icon \"%s\".\\n\\n" "${ICON_FILE}"
fi

echo "All done!"