Convert webp automation for systemd/openrc

webp-daemon.rc

#!/sbin/openrc-run
# /etc/init.d/webp-daemon

name="WebP Conversion Daemon"
description="Monitors and converts WebP files in home directory"
supervisor="supervise-daemon"
command="/usr/local/bin/webp-daemon.sh"
command_user="${RC_SVCNAME##*.}"
: ${command_user:=nobody}

# Set umask
umask 027

# Log file and pid path
output_log="/var/log/webp-daemon/webp-daemon.log"
error_log="/var/log/webp-daemon/error.log"
pidfile="/var/run/webp-daemon.pid"

# Dependency information
depend() {
    need localmount
    use logger
    after bootmisc
}

# Service-specific settings
start_pre() {
    checkpath -f -m 0644 -o "$command_user" "$output_log" "$error_log"
    checkpath -d -m 0755 -o "$command_user" "$(dirname "$output_log")"
}

# Change limits if needed
#rc_ulimit="-n 4096"

# Respawn settings for supervise-daemon
respawn_delay=5
respawn_max=10

webp-daemon.service

[Unit]
Description=WebP Conversion Daemon
After=network.target

[Service]
Type=simple
User=%i
ExecStart=/usr/local/bin/webp-daemon.sh
Restart=on-failure
RestartSec=5s

# Drop all capabilities and only retain what's needed
CapabilityBoundingSet=
# No capabilities needed for basic file operations in home directory
# when running as the user

# Additional security hardening
NoNewPrivileges=true
ProtectSystem=strict
ProtectHome=read-only
ReadWritePaths=%h
PrivateTmp=true
PrivateDevices=true
ProtectKernelTunables=true
ProtectControlGroups=true
RestrictAddressFamilies=AF_UNIX
RestrictNamespaces=true
LockPersonality=true
MemoryDenyWriteExecute=true
RestrictRealtime=true

[Install]
WantedBy=multi-user.target

webp-daemon.sh

#!/bin/bash
# webp-daemon.sh - A daemon that monitors for WebP files and converts them
# Required dependencies: inotify-tools, imagemagick

# Configuration
WATCH_DIR="$HOME"
LOG_FILE="/var/log/webp-daemon.log"
CONVERSION_FORMAT="png"  # Target format
PID_FILE="/var/run/webp-daemon.pid"

# Function to log messages
log() {
    echo "$(date '+%Y-%m-%d %H:%M:%S') - $1" >> "$LOG_FILE"
}

# Check for dependencies
if ! command -v inotifywait >/dev/null 2>&1; then
    echo "Error: inotifywait is required. Install inotify-tools package."
    exit 1
fi

if ! command -v magick >/dev/null 2>&1; then
    echo "Error: magick is required. Install ImageMagick package."
    exit 1
fi

# Create PID file
echo $$ > "$PID_FILE"

# Signal handling
cleanup() {
    log "Daemon stopping..."
    rm -f "$PID_FILE"
    exit 0
}

trap cleanup SIGINT SIGTERM

# Initialize
log "Starting WebP conversion daemon, monitoring: $WATCH_DIR"
log "Converting WebP to $CONVERSION_FORMAT"

# Main loop
inotifywait -m -r -e close_write --format '%w%f' "$WATCH_DIR" | while read -r FILE
do
    # Check if it's a WebP file
    if [[ "$FILE" == *.webp ]]; then
        log "Detected new WebP file: $FILE"
        
        # Get file information
        DIRNAME=$(dirname "$FILE")
        BASENAME=$(basename "$FILE" .webp)
        
        # Determine target filename with collision avoidance
        TARGET="$DIRNAME/$BASENAME.$CONVERSION_FORMAT"
        COUNTER=1
        while [ -f "$TARGET" ]; do
            TARGET="$DIRNAME/$BASENAME-$COUNTER.$CONVERSION_FORMAT"
            COUNTER=$((COUNTER + 1))
        done
        
        # Convert the file
        log "Converting to $TARGET"
        if magick "$FILE" "$TARGET"; then
            log "Conversion successful"
            
            # Remove original WebP file
            rm "$FILE"
            log "Removed original WebP file: $FILE"
        else
            log "Error: Conversion failed for $FILE"
        fi
    fi
done