pytest-xdist-load-testing

A pytest-xdist scheduler for continuous load testing with weighted test selection

Features

• Continuous Test Execution: Runs tests repeatedly until manually interrupted
• Weighted Test Selection: Control test execution frequency using the @weight decorator
• Random Selection: Tests are selected randomly based on their weights using random.choices
• Graceful Interruption: Tests and fixtures can stop the scheduler programmatically
• pytest-xdist Integration: Seamlessly integrates with pytest-xdist's distributed testing

Requirements

• Python 3.9+
• pytest >= 8.4.2
• pytest-xdist >= 3.8.0

Installation

pip install pytest-xdist-load-testing

Examples

See the examples/ folder for working examples.

Basic Load Testing

Run your tests with pytest-xdist to enable the load testing scheduler:

pytest --load-test -n 4 path/to/test_module.py  # Run with 4 workers

The scheduler will continuously supply tests to workers until interrupted (Ctrl+C).

Important: Load testing requires specifying a single test module. Running multiple modules will result in an error:

pytest --load-test -n 4 tests/  # ERROR: Multiple modules detected
pytest --load-test -n 4 test_a.py test_b.py  # ERROR: Multiple modules

This restriction ensures proper fixture handling and test isolation during continuous execution.

Stopping the Scheduler

Tests can stop the scheduler programmatically using the stop_load_testing function:

from pytest_xdist_load_testing import stop_load_testing

def test_with_stop_condition():
    result = check_system_health()
    if result.critical_failure:
        stop_load_testing("Critical failure detected")

Load Test with Weighted Distribution

from pytest_xdist_load_testing import weight

@weight(70)
def test_read_heavy():
    """70% of requests"""
    assert api.get("/data").status_code == 200

@weight(20)
def test_write_operations():
    """20% of requests"""
    assert api.post("/data", json={}).status_code == 201

@weight(10)
def test_admin_operations():
    """10% of requests"""
    assert api.delete("/data/old").status_code == 204

Command Line Options

The plugin adds the following command line option:

--load-test    Enable load testing mode with continuous test execution

Rate Limiting and Shared State

For rate limiting and shared state management across pytest-xdist workers, see the companion package pytest-xdist-rate-limit.

Documentation

📚 Full Documentation

• API Reference - Complete API documentation

License

Distributed under the terms of the MIT license, "pytest-xdist-load-testing" is free and open source software

Issues

If you encounter any problems, please file an issue along with a detailed description.

This pytest plugin was generated with Cookiecutter along with @hackebrot's cookiecutter-pytest-plugin template.