Autorun Backup on mounted disk

autorun.sh

#!/usr/bin/env bash

DIRECTORIES="/etc /home /usr/local /opt"
EXCLUDES="/home/chris/.local/share/Cryptomator"
USER=chris
MOUNT_LABEL="BackupDisk"
ALLOWED_MACHINES="CENTAURI"
RSYNC_PARAMETERS="-avPEHh --delete --stats --dry-run"

# Ensure rsync is available
if ! command -v rsync > /dev/null 2>&1; then
    echo "rsync is not installed. Please install rsync and try again."
    exit 1
fi

# Ensure the script is run as root
if [ "$(id -u)" -ne 0 ]; then
    echo "This script must be run as root. Please run again with sudo or as root."
    exit 1
fi

# Create a PID file to prevent multiple instances of the script
PIDFILE="/var/run/autorun-$MOUNT_LABEL.pid"

if [ -e "$PIDFILE" ] && kill -0 "$(cat "$PIDFILE")" 2>/dev/null; then
    echo "The script is already running (PID: $(cat "$PIDFILE")). Exiting."
    exit 0
fi

# Write the current PID to the PID file
echo $$ > "$PIDFILE"

# Ensure the PID file is removed on script exit
trap 'rm -f "$PIDFILE"' EXIT SIGINT SIGTERM

# Check if the script is running on an allowed machine
CURRENT_MACHINE=$(hostname)
if ! echo "$ALLOWED_MACHINES" | tr ' ' '\n' | grep -Fxq "$CURRENT_MACHINE"; then
    echo "This script is not allowed to run on this machine ($CURRENT_MACHINE)."
    exit 1
fi

if pidof systemd > /dev/null; then
    SERVICE_NAME="autorun-$MOUNT_LABEL.service"
    if ! systemctl is-enabled --quiet "$SERVICE_NAME" 2>/dev/null; then
        read -p "No enabled systemd service found for $SERVICE_NAME. Do you want to create and enable the systemd service? (y/n): " response
        if [ "$response" = "y" ]; then
            echo "Creating and enabling the systemd service..."

            SERVICE_FILE="/etc/systemd/system/$SERVICE_NAME"
            sudo tee $SERVICE_FILE > /dev/null <<EOF
[Unit]
Description=Autorun Backup Script for /media/$USER/$MOUNT_LABEL/
After=media-$USER-$MOUNT_LABEL.mount
Requires=media-$USER-$MOUNT_LABEL.mount

[Service]
Type=oneshot
User=root
ExecStart=/bin/bash -c '[ -f /media/$USER/$MOUNT_LABEL/autorun.sh ] && /media/$USER/$MOUNT_LABEL/autorun.sh'

[Install]
WantedBy=media-$USER-$MOUNT_LABEL.mount
EOF

            sudo systemctl daemon-reload
            sudo systemctl enable $SERVICE_NAME

            echo "Systemd service created and started successfully."
        else
            echo "Systemd service creation skipped."
            echo Systemd service found $SERVICE_NAME
        fi
    fi
else
    echo "Systemd is not running. Skipping systemd service creation."
fi

# Define the backup destination
BACKUP_DIR="/media/$USER/$MOUNT_LABEL/backup"
LOGS_DIR="/media/$USER/$MOUNT_LABEL/logs"

mkdir -p $BACKUP_DIR
mkdir -p $LOGS_DIR

TIMESTAMP=$(date +"%Y%m%d_%H%M%S")
LOG_FILE="$LOGS_DIR/rsync.$TIMESTAMP.log"

sudo -u $USER touch $LOG_FILE

for DIR in $DIRECTORIES; do
    EXCLUDE_PARAMS=""
    for EXCLUDE in $EXCLUDES; do
        if [ "${EXCLUDE#"$DIR"}" != "$EXCLUDE" ]; then
            EXCLUDE_PARAMS="$EXCLUDE_PARAMS --exclude=$EXCLUDE"
        fi
    done
    sudo rsync $RSYNC_PARAMETERS $EXCLUDE_PARAMS $DIR $BACKUP_DIR | tee -a $LOG_FILE
done


# Print a message indicating the backup is complete
echo "Backup completed successfully. Backup files are located in $BACKUP_DIR"