Utilities

A set of small, helper utilities for dealing with Python packages.

Reference

class packaging.utils.NormalizedName

A typing.NewType of str, representing a normalized name.

packaging.utils.canonicalize_name(name, validate=False)

This function takes a valid Python package or extra name, and returns the normalized form of it.

The return type is typed as NormalizedName. This allows type checkers to help require that a string has passed through this function before use.

If validate is true, then the function will check if name is a valid distribution name before normalizing.

Parameters:

• name (str) – The name to normalize.

• validate (bool) – Check whether the name is a valid distribution name.

Raises:

InvalidName – If validate is true and the name is not an acceptable distribution name.

>>> from packaging.utils import canonicalize_name
>>> canonicalize_name("Django")
'django'
>>> canonicalize_name("oslo.concurrency")
'oslo-concurrency'
>>> canonicalize_name("requests")
'requests'

packaging.utils.is_normalized_name(name)

Check if a name is already normalized (i.e. canonicalize_name() would roundtrip to the same value).

Parameters:

name (str) – The name to check.

>>> from packaging.utils import is_normalized_name
>>> is_normalized_name("requests")
True
>>> is_normalized_name("Django")
False

packaging.utils.canonicalize_version(version, strip_trailing_zero=True)

This function takes a string representing a package version (or a Version instance), and returns the normalized form of it. By default, it strips trailing zeros from the release segment.

Parameters:

version (str) – The version to normalize.

>>> from packaging.utils import canonicalize_version
>>> canonicalize_version('1.4.0.0.0')
'1.4'

packaging.utils.parse_wheel_filename(filename)

This function takes the filename of a wheel file, and parses it, returning a tuple of name, version, build number, and tags.

The name part of the tuple is normalized and typed as NormalizedName. The version portion is an instance of Version. The build number is () if there is no build number in the wheel filename, otherwise a two-item tuple of an integer for the leading digits and a string for the rest of the build number. The tags portion is an instance of Tag.

Parameters:

filename (str) – The name of the wheel file.

Raises:

InvalidWheelFilename – If the filename in question does not follow the wheel specification.

>>> from packaging.utils import parse_wheel_filename
>>> from packaging.tags import Tag
>>> from packaging.version import Version
>>> name, ver, build, tags = parse_wheel_filename("foo-1.0-py3-none-any.whl")
>>> name
'foo'
>>> ver == Version('1.0')
True
>>> tags == {Tag("py3", "none", "any")}
True
>>> not build
True

packaging.utils.parse_sdist_filename(filename)

This function takes the filename of a sdist file (as specified in the Source distribution format documentation), and parses it, returning a tuple of the normalized name and version as represented by an instance of Version.

Parameters:

filename (str) – The name of the sdist file.

Raises:

InvalidSdistFilename – If the filename does not end with an sdist extension (.zip or .tar.gz), or if it does not contain a dash separating the name and the version of the distribution.

>>> from packaging.utils import parse_sdist_filename
>>> from packaging.version import Version
>>> name, ver = parse_sdist_filename("foo-1.0.tar.gz")
>>> name
'foo'
>>> ver == Version('1.0')
True

exception packaging.utils.InvalidName

Raised when a distribution name is invalid.

exception packaging.utils.InvalidWheelFilename

Raised when a file name for a wheel is invalid.

exception packaging.utils.InvalidSdistFilename

Raised when a source distribution file name is considered invalid.