Async fixtures (pytest-asyncio) - Framework Patterns

Framework Mode - Async fixtures (pytest-asyncio)

Folder Structure

tests/
├── __init__.py
├── test_async_feature.py
├── conftest.py  # async fixtures here
utilities/
├── async_helpers.py
pytest.ini  # pytest config
requirements.txt

Test Framework Layers

• Test Layer: Async test functions using async def with pytest.mark.asyncio or pytest-asyncio plugin.
• Fixture Layer: Async fixtures defined with async def in conftest.py to setup async resources (e.g., database connections, web servers).
• Utility Layer: Async helper functions or classes to support tests, e.g., async HTTP clients.
• Configuration Layer: pytest.ini or pyproject.toml to enable pytest-asyncio plugin and set options.

Configuration Patterns

• Enable pytest-asyncio plugin in pytest.ini:

  [pytest]
  addopts = -p pytest_asyncio
  

• Use environment variables or pytest command line options to select async backend or environment.
• Store async resource credentials securely and inject via fixtures.
• Use conftest.py for shared async fixtures to avoid duplication.

Test Reporting and CI/CD Integration

• Use pytest's built-in reporting with --tb=short for concise tracebacks.
• Integrate with CI tools (GitHub Actions, GitLab CI) to run async tests automatically.
• Generate JUnit XML reports with --junitxml=report.xml for CI dashboards.
• Use coverage tools compatible with async code (e.g., pytest-cov) to measure test coverage.

Best Practices

• Always declare async fixtures with async def and use await inside them.
• Use pytest-asyncio plugin to enable async test support seamlessly.
• Keep async fixtures scoped appropriately (function, module) to optimize resource usage.
• Isolate async resources per test to avoid side effects and flaky tests.
• Use explicit await in tests and fixtures to ensure proper async execution.

Self Check

Where would you add a new async fixture that provides a mock async database connection for multiple tests?

Key Result

Organize async tests and fixtures in tests/ and conftest.py using pytest-asyncio for clean async test automation.