update-qbittorrent-port.sh

#!/bin/bash

# CONFIGURATION
GLUETUN_PORT_FILE="/container_path/gluetun/forwarded_port"
QBIT_HOST="http://localhost:8080"
QBIT_USER="[redacted]"
QBIT_PASS="[redacted]"
QBIT_CONTAINER_NAME="qbittorrent"
COOKIE_JAR="/tmp/qbit_cookies.txt"

# Check port file exists
if [[ ! -f "$GLUETUN_PORT_FILE" ]]; then
    echo "[!] Port file not found: $GLUETUN_PORT_FILE"
    exit 1
fi

# Read forwarded port from Gluetun
FORWARDED_PORT=$(cat "$GLUETUN_PORT_FILE" | tr -cd '[:digit:]')
if [[ -z "$FORWARDED_PORT" ]]; then
    echo "[!] Forwarded port is empty or invalid."
    exit 1
fi

# Login to qBittorrent API
curl -s --cookie-jar "$COOKIE_JAR" \
     -d "username=$QBIT_USER&password=$QBIT_PASS" \
     "$QBIT_HOST/api/v2/auth/login" > /dev/null

# Get current qBittorrent port
CURRENT_PORT=$(curl -s --cookie "$COOKIE_JAR" \
     "$QBIT_HOST/api/v2/app/preferences" | jq .listen_port)

# Fallback if port couldn't be read
if ! [[ "$CURRENT_PORT" =~ ^[0-9]+$ ]]; then
    echo "[!] Failed to read current qBittorrent port. Got: $CURRENT_PORT"
    exit 1
fi

# Compare and update if needed
if [[ "$CURRENT_PORT" -ne "$FORWARDED_PORT" ]]; then
    echo "[*] Updating qBittorrent port to $FORWARDED_PORT"

    curl -s --cookie "$COOKIE_JAR" \
         -d "json={\"listen_port\":$FORWARDED_PORT}" \
         "$QBIT_HOST/api/v2/app/setPreferences" > /dev/null

    # Restart qBittorrent container to apply changes (if needed)
    sudo /usr/bin/docker restart "$QBIT_CONTAINER_NAME" >/dev/null 2>&1
else
    # Optional: silent success
    :
fi

# Cleanup
rm -f "$COOKIE_JAR"