feat: Set up comprehensive Python testing infrastructure

[llbbl]

Set up comprehensive Python testing infrastructure

Summary

This PR establishes a complete testing infrastructure for the AWS ElastiCache examples repository, providing a unified testing environment across all Python projects in the repository.

Changes Made

Package Management & Dependencies

• Poetry Configuration: Created pyproject.toml with Poetry setup as the package manager
• Development Dependencies: Added comprehensive testing stack:
  • pytest (main testing framework)
  • pytest-cov (coverage reporting)
  • pytest-mock (mocking utilities)
  • pytest-asyncio (async testing support)
• Production Dependencies: Included common libraries used across examples:
  • boto3, redis, valkey-glide (core AWS/cache libraries)
  • flask, streamlit (web frameworks)
  • pandas, numpy (data processing)
  • pydantic, python-dotenv (utilities)

Testing Configuration

• pytest Configuration:
  • Custom markers: unit, integration, slow
  • Coverage threshold: 80%
  • Multiple report formats: HTML, XML, terminal
  • Strict options for better test quality
• Coverage Configuration:
  • Source paths covering all Python example directories
  • Comprehensive exclusion patterns
  • HTML and XML report generation

Directory Structure

tests/
├── __init__.py
├── conftest.py           # Shared fixtures
├── test_setup_validation.py  # Infrastructure validation
├── unit/
│   └── __init__.py
└── integration/
    └── __init__.py

Shared Test Fixtures

Created comprehensive fixtures in conftest.py:

• Environment: temp_dir, mock_env_vars, sample_data_dir
• AWS Mocking: mock_boto3_client, mock_aws_credentials
• Cache Mocking: mock_redis_client, mock_valkey_client
• Database: mock_database_connection, sample_config
• Utilities: mock_logger, sample_cache_data

Code Quality Tools

• Black: Code formatting (line length: 88)
• isort: Import sorting with Black profile
• Flake8: Linting
• mypy: Type checking with strict configuration

Running Tests

Install Dependencies

poetry install

Run Tests

# Run all tests
poetry run pytest

# Run with coverage
poetry run pytest --cov

# Run specific test categories
poetry run pytest -m unit
poetry run pytest -m integration
poetry run pytest -m slow

# Run with verbose output
poetry run pytest -v

View Coverage Reports

• Terminal: Coverage summary displayed after test run
• HTML: Open htmlcov/index.html in browser
• XML: coverage.xml for CI/CD integration

Configuration Details

Coverage Settings

• Threshold: 80% minimum coverage required
• Source Directories: All Python example directories included
• Exclusions: Test files, virtual environments, build artifacts
• Reports: HTML (htmlcov/), XML (coverage.xml), and terminal output

Testing Standards

• Python Version: 3.11+ required
• Test Discovery: Automatic discovery of test_*.py and *_test.py
• Markers: Use @pytest.mark.unit, @pytest.mark.integration, @pytest.mark.slow
• Fixtures: Extensive shared fixtures available for all tests

Next Steps

With this infrastructure in place, developers can now:

1. Write Unit Tests: Add tests in tests/unit/ for individual components
2. Write Integration Tests: Add tests in tests/integration/ for multi-component workflows
3. Use Shared Fixtures: Leverage pre-configured mocks and test data
4. Monitor Coverage: Ensure code quality with automated coverage reporting
5. Run Quality Checks: Use Black, isort, flake8, and mypy for code quality

Validation

The setup includes validation tests (test_setup_validation.py) that verify:

• ✅ pytest configuration and custom markers
• ✅ Shared fixtures functionality
• ✅ Mock clients (Redis, AWS, Database)
• ✅ Environment variable mocking
• ✅ Directory structure integrity
• ✅ Package imports and Python version compatibility

🤖 Generated with Claude Code