Design Restaurant Management System
Design a Restaurant Management System that handles table reservations, order placement, billing, and menu management using object-oriented design.
A Restaurant Management System is software that helps manage the day-to-day operations of a restaurant, including table reservations, order taking, kitchen coordination, billing, menu updates, and staff management.
It streamlines workflows, improves customer service, and increases overall efficiency.
In this chapter, we will explore the low-level design of a restaurant management system in detail.
Lets start by clarifying the requirements:
1. Clarifying Requirements
Before starting the design, it's important to ask thoughtful questions to uncover hidden assumptions and better define the scope of the system.
Here is an example of how a conversation between the candidate and the interviewer might unfold:
Candidate: Should customers be able to place orders directly, or will orders only be placed by staff (e.g., waiters or cashiers)?
Interviewer: Assume that staff will place the orders using the system. Customers will interact only through staff for now.
Candidate: Do we need to support table management—assigning customers to tables, merging or splitting tables, etc.?
Interviewer: Yes, table management is an important part. We should support assigning tables and tracking which table placed which order.
Candidate: Should the kitchen receive real-time updates for new orders and status changes?
Interviewer: Yes, the kitchen should be able to see all incoming orders in real-time and update the status (e.g., preparing, ready).
Candidate: Do we need to track payments, or is this out of scope?
Interviewer: Yes, basic payment tracking should be included—order total, payment status (paid/unpaid), and payment mode (cash, card).
Candidate: Generate receipt after payment?
Interviewer: Yes
After gathering the details, we can summarize the key system requirements.
1.1 Functional Requirements
- Allow staff to create, and cancel dine-in orders
- Support menu browsing and item selection
- Support assigning and managing tables for dine-in customers
- Maintain real-time order status (placed, preparing, ready, completed)
- Display all new and pending orders to kitchen staff in real-time
- Allow updating item availability in the menu
- Track order totals and payment status (paid/unpaid)
- Support basic payment details including amount and payment mode
- Maintain a history of orders by date, table, and order ID
1.2 Non-Functional Requirements
- Modularity: The system should be organized into separate components like MenuService, OrderService, TableService, and PaymentService
- Scalability: The system should support multiple concurrent orders and real-time updates across staff and kitchen terminals
- Extensibility: The design should allow future enhancements like delivery support, digital receipts, loyalty points, and customer feedback
- Responsiveness: Order placements, updates, and kitchen dashboards should reflect changes in real-time
- Maintainability: Code should follow object-oriented principles and be easy to test and extend
- Reliability: The system should prevent order duplication or data loss in the event of system restarts
- Security: Sensitive operations like payment processing should be access-controlled