Functional Requirements

User Management

• Allow users to register and create an account.
• Allow users to log in and securely access their profile.
• Allow users to view and manage their reservations.

Parking Reservation

• Allow users to search for available parking spots.
• Show real-time parking spot availability.
• Allow users to book a parking spot for a selected date and time.
• Assign the reserved parking spot automatically to the user.
• Allow users to modify or cancel reservations.

Payment Management

• Process reservation payments securely.
• Support multiple payment methods (credit card, debit card, digital wallets).
• Generate payment confirmation and transaction receipts.

Access Control

• Generate a digital ticket or QR code for parking access.
• Allow user check-in upon arrival.
• Allow user check-out when leaving the parking facility.
• Control vehicle entry and exit through automated gates.

Reservation Monitoring

• Detect no-show reservations after a defined grace period.
• Automatically release unused parking spots back into availability.
• Update parking spot status in real time.

Notification System

• Send booking confirmations.
• Send payment confirmations.
• Send reminders before reservation time.
• Notify users about reservation expiration or cancellation.

Non-Functional Requirements

Performance

• The system must respond to user requests within a few seconds.
• Real-time parking availability updates must occur instantly or with minimal delay.

Reliability

• The system must operate continuously and stably without failures.
• Reservation and payment processes must be completed accurately.

Security

• User personal data must be protected.
• Payment information must be encrypted and processed securely.
• Authentication and authorization mechanisms must prevent unauthorized access.

Scalability

• The system must support multiple concurrent users.
• The system must handle increased demand during peak usage periods.

Availability

• The service must be accessible 24/7.
• Downtime must be minimized through fault-tolerant infrastructure.

Data Consistency

• Parking spot availability information must always be accurate and synchronized.
• Reservation data must remain consistent across all system components.

Maintainability

• The system should be easy to update and maintain.
• New features should be added without major architectural changes.

API Design

Define the APIs expected from the system. This is your chance to analyze and define the read and write paths so that you can come up with the high-level design...

High-Level Design

1. User Application (Web/Mobile)

Interface used by customers to:

• Register and log in
• Search available parking spots
• Make reservations
• Complete payments
• Receive QR codes or tickets
• Check reservation status

2. Parking Management System

Core system responsible for:

• Managing parking spot availability
• Handling reservations
• Assigning parking spaces
• Managing check-in/check-out
• Releasing no-show reservations

3. Payment System

Responsible for:

• Processing payments securely
• Verifying transactions
• Generating invoices and receipts

4. Gate Control System

Responsible for:

• Scanning QR codes or tickets
• Opening and closing entry/exit gates
• Validating active reservations
• Recording vehicle entry and exit

5. Parking Spot Monitoring System

Responsible for:

• Detecting occupied and free parking spots using sensors
• Sending real-time updates to the management system
• Monitoring parking utilization

6. Database

Stores:

• User accounts
• Reservations
• Parking spot information
• Payment records
• Entry/exit logs

7. Notification Service

Responsible for:

• Sending emails, SMS, or app notifications
• Booking confirmations
• Payment confirmations
• Reservation reminders

Detailed Component Design

Parking Management System

Main Responsibilities

• Handle reservation requests
• Check parking spot availability
• Assign available spots
• Update reservation status
• Manage cancellations and no-shows

Internal Modules

• Reservation Manager
• Availability Checker
• Spot Assignment Engine
• Check-in/Check-out Manager

Payment System

Main Responsibilities

• Validate payment information
• Process transactions
• Confirm successful payments
• Handle failed transactions and refunds

Internal Modules

• Payment Gateway Integration
• Transaction Validator
• Receipt Generator

Gate Control System

Main Responsibilities

• Validate QR codes or digital tickets
• Control physical gate access
• Log vehicle entry and exit

Internal Modules

• QR Code Scanner
• Access Validator
• Gate Controller
• Entry/Exit Logger