Payment Processing Service

Comprehensive payment solution supporting subscriptions, one-time payments, and revenue management

Requirements Document

Comprehensive requirements for the Payment Processing Service microservice in the KnowledgeTracker Platform.

1. Functional Requirements

1.1 Payment Methods

  • Credit/Debit card payments (Visa, MasterCard, Amex)
  • Digital wallets (PayPal, Apple Pay, Google Pay)
  • Bank transfers and ACH payments
  • Cryptocurrency payments (optional)
  • Saved payment methods for returning customers

1.2 Subscription Management

  • Recurring billing (monthly, quarterly, annual)
  • Multiple subscription tiers and plans
  • Subscription upgrades, downgrades, and cancellations
  • Trial periods and promotional pricing
  • Automatic renewal and expiration handling
  • Proration for mid-cycle changes

1.3 One-Time Payments

  • Course purchase and enrollment fees
  • Certificate fees and exam payments
  • Bundle deals and package purchases
  • Shopping cart functionality for multiple items

1.4 Refunds & Chargebacks

  • Full and partial refund processing
  • Refund policy enforcement (time limits, conditions)
  • Chargeback dispute management and documentation
  • Automated refund approval workflows

1.5 Discounts & Coupons

  • Percentage and fixed-amount discount codes
  • Time-limited promotional campaigns
  • Single-use and multi-use coupon codes
  • Course-specific and platform-wide discounts
  • Student and bulk purchase discounts

1.6 Revenue Reporting

  • Transaction history and detailed payment logs
  • Revenue dashboards by course, instructor, and period
  • Tax calculation and reporting (VAT, sales tax)
  • Invoice generation and delivery
  • Financial reconciliation and accounting exports

1.7 Multi-Tenant Revenue Split

  • Revenue sharing between platform and organizations
  • Instructor payout management and scheduling
  • Configurable commission structures per organization

2. Non-Functional Requirements

2.1 Security

  • PCI DSS Level 1 compliance for card data handling
  • Tokenization of payment methods (no raw card storage)
  • 3D Secure (3DS) authentication for fraud prevention
  • Encrypted transmission of all payment data
  • Fraud detection and risk scoring

2.2 Reliability

  • 99.99% payment processing uptime
  • Idempotent payment processing (no duplicate charges)
  • Automatic retry for failed transactions with exponential backoff
  • Payment gateway failover to backup providers

2.3 Performance

  • Payment authorization response time < 3 seconds
  • Support for 1,000+ concurrent payment transactions
  • Webhook processing within 5 seconds of payment events

2.4 Compliance

  • GDPR compliance for customer payment data
  • SOC 2 Type II compliance for financial operations
  • Support for international tax regulations (VAT, GST)

3. Integration Requirements

3.1 Internal Microservices

  • User Management: User identification and billing details
  • Course Management: Course pricing and enrollment activation
  • Notification Service: Payment confirmations and receipt delivery
  • Analytics: Revenue tracking and payment metrics

3.2 External Services

  • Payment Gateways: Stripe, PayPal, Razorpay
  • Tax Services: TaxJar, Avalara for automated tax calculation
  • Accounting: QuickBooks, Xero integration for bookkeeping

Requirements Validation

Use this requirements document alongside the Database Design to validate:

  • All payment types and methods are properly tracked
  • Subscription lifecycle and billing cycles are modeled
  • Refund and chargeback processes have supporting data structures
  • Revenue reporting and tax compliance can be generated
  • Multi-tenant revenue split is properly implemented