Video Streaming Subscription Service API

A production-quality REST API for a video streaming subscription platform. The application allows users to register for a free trial account and process subscription payments through secure backend endpoints.

Features

• User registration system
• Validation for usernames, passwords, emails, dates of birth, and credit card numbers
• Age restriction enforcement (18+ only)
• Duplicate username detection
• Payment processing endpoint
• User filtering based on credit card registration
• HTTP status-based error handling
• Unit testing support
• No database required

User Validations

• Username must be alphanumeric with no spaces
• Password must:
  • be at least 8 characters long
  • contain at least one uppercase letter
  • contain at least one number
• Email must be valid
• Date of Birth must follow ISO 8601 format
• Credit card number is optional but must contain 16 digits if provided
• Users must be at least 18 years old

Payment Validations

• Credit card number must contain 16 digits
• Amount must be a valid 3-digit number
• Credit card must belong to a registered user

Prerequisites: Java 17 or later