I’ve been getting into server stuff lately. Having a NAS is great, especially when you can access it via the internet (I use WireGuard to access my home network.) No more flash drives!

One thing I did lately was create a script to backup the contents of each of my computers to a backup share on the NAS. Since I tend to copy a lot of files from the NAS to my local computers though I wanted a script that would be a bit more selective, that way I’m not copying tons of files that already exist elsewhere on the NAS. For those files I don’t want to backup I generally keep them in a directory called ~/not-backed-up/

To do that I just have to edit the script for each computer it’s on, just the destination and dirs variables at the top.

Then just make it an executable script:
$ chmod +x backup-laptop.sh
and run it:
$ ./backup-laptop.sh

#~/bin/bash

# MAKE SURE TO USE ABSOLUTE PATHS!!

# this is the backup destination, set it to whatever is needed
destination="/Volumes/BackupServer/macbook-m3"

# enter full paths of files/folders to backup. make sure 
# to omit the slash at the end so the folder itself 
# will be copied too instead of just the contents in it
dirs=(
    "/Users/me/Documents"
    "/Users/me/Desktop"
    "/Users/me/Pictures"
    "/Users/me/Movies"
    "/Users/me/Downloads"
    "/Users/me/DataGripProjects"
    "/Users/me/Documents"
    "/Users/me/programming"

    "/Users/me/.gitconfig"
    "/Users/me/.vimrc"

    "/etc/hosts"
)

function print_message() {
    # need to add or remove the -e flag depending on Mac OS or not
    local msg=$1
    if [[ "$OSTYPE" == "darwin"* ]]; then
        echo "$msg"
    else
        echo -e "\t$msg"
    fi
}



# check if the user said to auto-continue by passing the "-y" argument
confirm=false
if [[ "$1" == "-y" ]]; then
    confirm=true
fi

# tell user what we're backing up and to where
print_message "rsync destination:"
print_message "$destination"

print_message "local directories being backed up: "
for src in "${dirs[@]}"; do
    print_message "\t$src"
done

# if the user didn't pass the -y flag then we ask if they want to continue
if [[ "$confirm" == false ]]; then 
  print_message "\r\nPlease note the source directories cannot end in / if any do, fix the script and re-run. "

  # prompt the user to continue (if needed)
  while true; do
    read -p "Continue backup? (y/n): " response
    case "$response" in 
      [Yy]*) # just checks first letter is y for yes
        print_message "Continuing..."
        break;
        ;;
      [Nn]*) # first letter is n for no
        print_message "Exiting."
        exit 1
        ;;
      *)
        print_message "Invalid response. Please answer yes or no."
        # loop back to top of while and ask again
        ;;
    esac
  done
else
    print_message "\r\nDetected '-y' flag, skipping confirmation"
fi

# echo "Running rsync command..."
print_message "Running rsync command..."

# do the actual backup
rsync -rh --update --delete --stats --info=progress2 "${dirs[@]}" "$destination"

print_message "\r\nFinished backup."