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