Lock Files

Parse and validate pylock.toml files.

Usage

import tomllib
from pathlib import Path

from packaging.pylock import Package, PackageWheel, Pylock
from packaging.utils import NormalizedName
from packaging.version import Version

# validate a pylock file name
assert is_valid_pylock_path(Path("pylock.example.toml"))

# parse and validate pylock file
toml_dict = tomllib.loads(Path("pylock.toml").read_text(encoding="utf-8"))
pylock = Pylock.from_dict(toml_dict)
# the resulting pylock object is validated against the specification,
# else a PylockValidationError is raised

# generate a pylock file
pylock = Pylock(
    lock_version=Version("1.0"),
    created_by="some_tool",
    packages=[
        Package(
            name=NormalizedName("example-package"),
            version=Version("1.0.0"),
            wheels=[
                PackageWheel(
                    url="https://example.com/example_package-1.0.0-py3-none-any.whl",
                    hashes={"sha256": "0fd.."},
                )
            ],
        )
    ],
)
toml_dict = pylock.to_dict()
# use a third-party library to serialize to TOML

# you can validate a manually constructed Pylock class
pylock.validate()

# select packages to install for the current environment
for package, artifact in pylock.select():
    print(f"Install {package.name} from {artifact}")

Reference

The following frozen keyword-only dataclasses are used to represent the structure of a pylock file. The attributes correspond to the fields in the pylock file specification.

class packaging.pylock.Package

class packaging.pylock.PackageWheel

class packaging.pylock.PackageSdist

class packaging.pylock.PackageArchive

class packaging.pylock.PackageVcs

class packaging.pylock.PackageDirectory

The following exceptions may be raised by this module: