Add comprehensive testing suite for S3 operations and error scenarios

[Asi0Flammeus]

Description

The codebase lacks comprehensive testing, especially for S3 operations, error scenarios, and security features implemented in PR #22.

Testing Gaps

• No tests for S3 file operations
• Missing error scenario testing (S3 failures, invalid inputs)
• No security testing for JWT implementation
• Lack of integration tests for end-to-end workflows
• No load testing for file upload endpoints

Required Test Categories

1. Unit Tests

• S3 utility functions
• Input validation functions
• JWT token generation/validation
• Rate limiting functionality
• Configuration migration logic

2. Integration Tests

• End-to-end S3 workflows
• API authentication flows
• File upload/download cycles
• Error propagation through system

3. Security Tests

• JWT token validation edge cases
• S3 path traversal attempts
• Rate limiting enforcement
• Input validation bypass attempts
• File size limit enforcement

4. Error Scenario Tests

• S3 service unavailable
• Invalid file formats
• Network timeouts
• Malformed requests
• Missing credentials

5. Load Tests

• File upload endpoint stress testing
• Concurrent request handling
• Rate limit behavior under load
• Memory usage during large uploads

Test Infrastructure

• Use pytest for unit/integration tests
• Add fixtures for S3 mocking (moto library)
• Create test data sets for different scenarios
• Add performance benchmarking tools
• Set up CI/CD test automation

Acceptance Criteria

• 80%+ code coverage for new S3 functionality
• All error scenarios have corresponding tests
• Security features tested against common attacks
• Load tests demonstrate system limits
• All tests pass in CI/CD pipeline

Related

• Testing recommendations from PR Create API endpoints for contribute app #22 review
• Supports quality assurance for new features

Priority

Low - Quality assurance and validation