Manage a Local Node.js Development Server

#!/bin/bash

# Usage:
#   ./dev_server.sh start <command> (e.g., ./dev_server.sh start "npm run dev")
#   ./dev_server.sh stop
#   ./dev_server.sh status

PID_FILE=".server.pid"

start_server() {
    if [ -f "$PID_FILE" ]; then
        PID=$(cat "$PID_FILE")
        if ps -p "$PID" > /dev/null; then
            echo "Server is already running with PID $PID."
            exit 0
        else
            echo "Stale PID file found. Removing it."
            rm "$PID_FILE"
        fi
    fi

    if [ -z "$1" ]; then
        echo "Error: Start command is required. E.g., '$0 start \"npm run dev\"'"
        exit 1
    fi

    COMMAND="$@"
    echo "Starting server with command: $COMMAND"
    nohup bash -c "$COMMAND" > server.log 2>&1 & # Run in background, log output
    echo $! > "$PID_FILE"
    echo "Server started with PID $(cat "$PID_FILE"). Log available in server.log"
}

stop_server() {
    if [ -f "$PID_FILE" ]; then
        PID=$(cat "$PID_FILE")
        if ps -p "$PID" > /dev/null; then
            echo "Stopping server with PID $PID..."
            kill "$PID"
            rm "$PID_FILE"
            echo "Server stopped."
        else
            echo "No running server found with PID $PID. Removing stale PID file."
            rm "$PID_FILE"
        fi
    else
        echo "No PID file found. Server might not be running or wasn't started with this script."
    fi
}

server_status() {
    if [ -f "$PID_FILE" ]; then
        PID=$(cat "$PID_FILE")
        if ps -p "$PID" > /dev/null; then
            echo "Server is running with PID $PID."
            echo "Check server.log for output."
        else
            echo "Server PID $PID found in .pid file, but process is not running. Stale PID file?"
            echo "Consider running '$0 stop' to clean up."
        fi
    else
        echo "Server is not running (no PID file found)."
    fi
}

case "$1" in
    start)
        shift
        start_server "$@"
        ;;
    stop)
        stop_server
        ;;
    status)
        server_status
        ;;
    *)
        echo "Usage: $0 {start \"<command>\"|stop|status}"
        exit 1
        ;;
esac