Gets ProductVersion and BuildVersion from an OS X/macOS Installer App

installer_vers

#!/bin/bash
APP="${1}"

if [ -z "${APP}" ]; then
  echo "Usage: $(basename ${0}) INSTALL_APP"
  exit 1
fi

tmp_dir=$(/usr/bin/mktemp -d)
ESD_DIR="${tmp_dir}/esd"
BASE_DIR="${tmp_dir}/base"
PLIST="${BASE_DIR}/System/Library/CoreServices/SystemVersion.plist"

cleanup() {
  /usr/bin/hdiutil eject -quiet "${BASE_DIR}"
  /usr/bin/hdiutil eject -quiet "${ESD_DIR}"
  rm -rf "${tmp_dir}"
}

trap cleanup EXIT

die () {
  echo "${1}"
  exit 1
}

mkdir "${ESD_DIR}"
mkdir "${BASE_DIR}"

if [ -f "${APP}/Contents/SharedSupport/InstallESD.dmg" ]; then
  /usr/bin/hdiutil attach "${APP}/Contents/SharedSupport/InstallESD.dmg" -quiet -mountpoint "${ESD_DIR}" -nobrowse -noverify || die "Problem getting version. Maybe InstallESD.dmg is already mounted?"
  /usr/bin/hdiutil attach "${ESD_DIR}/BaseSystem.dmg" -quiet -mountpoint "${BASE_DIR}" -nobrowse -noverify || die "Problem getting version. Maybe BaseSystem.dmg is already mounted?"

  version=$(defaults read "${PLIST}" ProductVersion)
  build=$(defaults read "${PLIST}" ProductBuildVersion)

  printf "ProductVersion:\t%s\nBuildVersion:\t%s\n" "${version}" "${build}"
else
  die "${APP} does not appear to be a macOS Installer App"
fi