Testing Strategy

Comprehensive testing is crucial.

Unit Tests

• Focus: Individual functions, modules, classes within each microservice.
• Tools: Jest (for Node.js/TypeScript).
• Coverage: Aim for high coverage (>80%) for business-critical logic.

Integration Tests

• Focus: Interactions between components within a single microservice (e.g., API endpoint to database) or between closely coupled services (mocking external dependencies).
• Tools: Jest + Supertest (for API endpoint testing), Prisma test utilities for DB interactions. For Cloud Functions/Run, test their triggers and responses.

End-to-End (E2E) Tests

• Focus: Test complete user flows through the UI and APIs.
• Tools: Playwright or Cypress for UI E2E tests. API E2E tests can be written with Jest/Supertest or a tool like Postman/Newman against a deployed test environment.
• Scope: Critical paths like agent registration, device setup, recharge notification flow, payout request.

Load Testing

• Focus: System performance and stability under expected and peak load, particularly for the Transaction Ingestion API and core processing services.
• Tools: k6, Artillery, or GCP Cloud Load Testing.
• Metrics: Response times, error rates, resource utilization (CPU, memory, DB connections) under load. Test against documented low concurrency initially (100 users) and identify bottlenecks.