Add torrent to remote Transmission instance from browser

transmission_add_magnet_torrent.sh

#!/usr/bin/env bash

# Use your browser to add a torrent to a remote Transmission instance. 
# Works for magnet links only. 
# Requires "transmission-remote".
# For desktop popups "kdialog" (for KDE) or "zenity" (for Gnome) required. 

# USAGE:
  # Put this script on your local host, make it executable (chmod +x <script name>).
  # Update the port and hostname settings below, lines 23 and 25. 
  # In your browser settings set this script as the application to handle magnet links. 
  # Assumes HTTPS, remove "--ssl" on line 48 if not.

# Script exits successfully (0) if we're able to add the torrent. 
# Exits with error (1) if we can't.

set -Eeuo pipefail
trap cleanup SIGINT SIGTERM ERR EXIT

link="$1"

# Port number for Transmission
port=""
# Hostname for Transmission
hostname=""

cleanup(){
  trap - SIGINT SIGTERM ERR EXIT
  if [ ! -z "${success_msg+x}" ]; then
  	if [[ $DESKTOP_SESSION == "plasma" ]]; then
  		kdialog --title "Magnet Manager" --passivepopup "$success_msg" 10
  	elif [[ $DESKTOP_SESSION == "gnome" ]]; then
  		zenity --info --title "Magnet Manager" --text "$success_msg"
  	fi
  	echo "$success_msg"
  fi
  if [ ! -z "${error_msg+x}" ]; then
  	if [[ $DESKTOP_SESSION == "plasma" ]]; then
  	kdialog --title "Magnet Manager" --error "Failed to add torrent; $error_msg" 10
  	elif [[ $DESKTOP_SESSION == "gnome" ]]; then
  		zenity --error --title "Magnet Manager" --text "$error_msg"
  	fi
  	echo "$exit_msg"
  fi
}

add_magnet(){
	add_torrent=$(transmission-remote "$hostname":"$port" "--ssl" "-a" $link || true)
	if [[ $add_torrent == *"success"* ]]; then
		success_msg="Torrent added to Transmission."
		exit 0
	else
		error_msg="$add_torrent"
		exit 1
	fi
}

add_magnet