pep517 0.8.1

PEP 517 specifies a standard API for systems which build Python packages.

This package contains wrappers around the hooks specified by PEP 517. It provides:

• A mechanism to call the hooks in a subprocess, so they are isolated from the current process.

• Fallbacks for the optional hooks, so that frontends can call the hooks without checking which are defined.

• Higher-level functions which install the build dependencies into a temporary environment and build a wheel/sdist using them.

Run the tests with pytest or tox.

High level usage, with build requirements handled:

import os
from pep517.envbuild import build_wheel, build_sdist

src = 'path/to/source'  # Folder containing 'pyproject.toml'
destination = 'also/a/folder'
whl_filename = build_wheel(src, destination)
assert os.path.isfile(os.path.join(destination, whl_filename))

targz_filename = build_sdist(src, destination)
assert os.path.isfile(os.path.join(destination, targz_filename))

Lower level usage—you are responsible for ensuring build requirements are available:

import os
import toml
from pep517.wrappers import Pep517HookCaller

src = 'path/to/source'  # Folder containing 'pyproject.toml'
with open(os.path.join(src, 'pyproject.toml')) as f:
    build_sys = toml.load(f)['build-system']

print(build_sys['requires'])  # List of static requirements

hooks = Pep517HookCaller(
    src,
    build_backend=build_sys['build_backend'],
    backend_path=build_sys.get('backend-path'),
)

config_options = {}   # Optional parameters for backend
# List of dynamic requirements:
print(hooks.get_requires_for_build_wheel(config_options))

destination = 'also/a/folder'
whl_filename = hooks.build_wheel(destination, config_options)
assert os.path.isfile(os.path.join(destination, whl_filename))

To test the build backend for a project, run in a system shell:

python3 -m pep517.check path/to/source  # source dir containing pyproject.toml

To build a backend into source and/or binary distributions, run in a shell:

python -m pep517.build path/to/source  # source dir containing pyproject.toml

This ‘build’ module should be considered experimental while the PyPA decides on the best place for this functionality.