GiftCard Service — Requirements and Use Case Design

Overview

1. Functional Requirements

• User registration and authentication (JWT-based)
• User profile management (view, update, partial update)
• Browsing available gift card types
• Creating gift card orders (purchase)
• Viewing user orders
• Retrieving details of specific gift cards
• Redeeming gift cards securely
• Admin user management (CRUD on users)
• Admin management of gift card types
• Error handling and validation on all user inputs
• Role-based access control (users vs admins)

2. Non-Functional Requirements

• Scalability: System must support increasing users and orders without performance degradation
• High Availability: 99.9% uptime with fault tolerance and automatic failover mechanisms
• Security: JWT-based authentication, encrypted passwords, secure gift card codes
• Performance: API response times under 200ms for standard operations
• Data Privacy: GDPR compliance for user information and order history protection
• Validation: Comprehensive input validation with detailed error responses
• Documentation: Complete API documentation using Swagger/OpenAPI specification
• Monitoring: Comprehensive logging for security audits and system monitoring
• Data Integrity: ACID transactions for financial operations and gift card redemptions
• Backup & Recovery: Automated daily backups with point-in-time recovery capabilities

3. Use Cases

Use Case	Description	Actor
Register User	New user signs up with email, password, and profile info.	Customer
Login User	User logs in and receives JWT token for session management.	Customer
View/Edit Profile	User views or updates own profile information.	Customer
Browse Gift Card Types	User fetches list of available gift card types.	Customer
Place Order	User creates an order for one or multiple gift cards.	Customer
View User Orders	User views list and details of own gift card orders.	Customer
Redeem Gift Card	User redeems a gift card by unique identifier and updates balance/status.	Customer
Admin Manage Users	Admin views, updates, or deletes user accounts.	Admin
Admin Manage Card Types	Admin creates, updates, or deletes gift card types.	Admin
View Order Analytics	Admin views system-wide order statistics and analytics.	Admin

4. Objects, Classes, and Relationships

4.1 Core Business Objects

The system identifies the following core business objects:

User: Represents customers and administrators who interact with the system

• Attributes: ID, firstName, lastName, email, password, roles
• Responsibilities: Authentication, profile management, order placement

Role: Defines access permissions and user types

• Attributes: roleName, users
• Responsibilities: Authorization, access control

Order: Represents purchase transactions for gift cards

• Attributes: ID, user, giftCards, orderDate, status, totalPrice
• Responsibilities: Transaction management, order tracking

GiftCard: Individual gift card instances with unique codes

• Attributes: ID, code, balance, expirationDate, redeemed, creationDate, giftCardType, order
• Responsibilities: Balance tracking, redemption management, expiration handling

GiftCardType: Templates defining gift card categories

• Attributes: ID, name, currency
• Responsibilities: Card type definition, currency management

OrderStatus: Enumeration defining order states

• Values: PENDING, COMPLETED, FAILED
• Responsibilities: Order state management

4.2 Key Relationships

• User ↔ Role: Many-to-Many relationship (users can have multiple roles)
• User → Order: One-to-Many relationship (user can place multiple orders)
• Order → GiftCard: One-to-Many relationship (order can contain multiple gift cards)
• GiftCardType → GiftCard: One-to-Many relationship (one type can be used for multiple cards)
• Order → OrderStatus: Each order has one status from the enumeration

5. Class Diagram

6. CRC Cards Summary

Class	Responsibilities	Collaborators
User	Manage user authentication and profile data • Handle user registration and login • Maintain user roles and permissions	Order, GiftCard, Role
Role	Define user access levels • Manage authorization permissions • Control system access	User
Order	Process purchase transactions • Track order status and history • Calculate total prices • Manage order lifecycle	User, GiftCard, OrderStatus
GiftCard	Store individual gift card details • Handle redemption logic • Track balance and expiration • Generate unique codes	User, GiftCardType, Order
GiftCardType	Define gift card categories • Specify currency and naming • Template for gift card creation	GiftCard
OrderStatus	Define valid order states • Ensure proper state transitions • Provide status validation	Order

7. ER Diagram