A boilerplate script for retrieving and installing .deb files, using TeamViewer as an example. Easy to modify!

boilerplate.sh

#!/usr/bin/env bash
#
# boilerplate
# 
# A boilerplate script for retrieving and installing .deb files, using TeamViewer as an example. Easy to modify!
#
# Author: M. Krinitz
# Date: 2021.07.31
# License: MIT

PACKAGE_NAME="teamviewer"
URL="https://download.teamviewer.com/download/linux/teamviewer_amd64.deb"
DEB="teamviewer_amd64.deb"
DOWNLOAD_DESTINATION="$HOME/Downloads"

# If not Debian-based OS, exit.

check_OS () {
 printf "%s\\n" "Checking OS version..."
 
  if [[ ! -f "/etc/debian_version" ]]; then
     printf "%s\\n" "NOT a Debian-based OS. Exiting."
     exit 1

  else
    printf "%s\\n" "Debian-based OS detected. Continuing..." 
fi
}

# If package detected, exit.

check_package () {
  printf "%s\\n" "Checking for installed version of: $PACKAGE_NAME..."

  if dpkg-query --show --showformat='${Status}' "$PACKAGE_NAME" | grep "ok installed" &>/dev/null ; then
    printf "%s\\n" "Installed version of: $PACKAGE_NAME DETECTED. Exiting."
    exit 1

  else
    printf "%s\\n" "Installed version of: $PACKAGE_NAME NOT DETECTED. Continuing..."
fi
}

# Retrieve package, and place in logged in user's Downloads directory.

get_package () {
  printf "%s\\n" "Retrieving: $PACKAGE_NAME..."

  wget --progress=bar --tries=3 --wait=5 --continue "$URL" --output-document="$DOWNLOAD_DESTINATION"/"$DEB"

}

# Use apt to install the .deb file.

install_package () {
  printf "%s\\n" "Installing: $PACKAGE_NAME..."

  sudo apt --yes install ./"$DOWNLOAD_DESTINATION"/"$DEB"
}

# Get exit status.

exit_status () {
  if [[ $retVal -ne 0 ]]; then
    printf "%s\\n" "Something went wrong, homie..."

  else
    printf "%s\\n" "Done."
fi
}

main () {

printf "%s\\n" "Running $PACKAGE_NAME installer."

check_OS
check_package
get_package
install_package

}

main "$@"

retVal=$?
exit_status