No project description provided
Project description
[![CircleCI](https://circleci.com/gh/AdamGleave/pytest-shard.svg?style=svg)](https://circleci.com/gh/AdamGleave/pytest-shard)
# pytest-shard
Shards tests based on a hash of their test name enabling easy parallelism across machines, suitable for a wide variety of continuous integration services. Tests are split at the finest level of granularity, individual test cases, enabling parallelism even if all of your tests are in a single file (or even single parameterized test method).
## Features
pytest-shard aims for simplicity. When installed, simply run:
` $ pytest --shard-id=I --num-shards=N `
where I is the index of this shard and N the total number of shards. For example, to split tests across two machines:
` # On machine 1: $ pytest --shard-id=0 --num-shards=2 # On machine 2: $ pytest --shard-id=1 --num-shards=2 `
The intended use case is for continuous integration services that allow you to run jobs in parallel. For CircleCI, enable [parallelism](https://circleci.com/docs/2.0/parallelism-faster-jobs/) and then use: ` pytest --shard-id=${CIRCLE_NODE_INDEX} --num-shards=${CIRCLE_NODE_TOTAL} `
On Travis, you must define the environment variables explicitly, but can use a [similar approach](https://docs.travis-ci.com/user/speeding-up-the-build/).
## Alternatives
[pytest-xdist](https://github.com/pytest-dev/pytest-xdist) allows you to parallelize tests across cores on a single machine, and can also schedule tests on a remote machine. I use pytest-shard to split tests across CI workers, and pytest-xdist to parallelize across CPU cores within each worker.
pytest-shard does not take into account the run time of tests, which can lead to suboptimal allocations. [pytest-circleci-parallelized](https://github.com/ryanwilsonperkin/pytest-circleci-parallelized) uses test run time, but can only split at the granularity of classes, and is specific to CircleCI.
Please open a PR if there are other promising alternatives that I have overlooked.
## Installation
You can install pytest-shard via pip:
` $ pip install pytest-shard `
## Contributions
Contributions are welcome. Test may be run using tox.
## License
This software is MIT licensed.
Project details
Release history Release notifications | RSS feed
Download files
Download the file for your platform. If you're not sure which to choose, learn more about installing packages.