Tags ==== .. currentmodule:: packaging.tags Wheels encode the Python interpreter, ABI, and platform that they support in their filenames using `platform compatibility tags`_. This module provides support for both parsing these tags as well as discovering what tags the running Python interpreter supports. Usage ----- .. doctest:: >>> from packaging.tags import Tag, sys_tags >>> import sys >>> looking_for = Tag("py{major}".format(major=sys.version_info.major), "none", "any") >>> supported_tags = list(sys_tags()) >>> looking_for in supported_tags True >>> really_old = Tag("py1", "none", "any") >>> wheels = {really_old, looking_for} >>> best_wheel = None >>> for supported_tag in supported_tags: ... for wheel_tag in wheels: ... if supported_tag == wheel_tag: ... best_wheel = wheel_tag ... break >>> best_wheel == looking_for True Reference --------- High Level Interface '''''''''''''''''''' The following functions are the main interface to the library, and are typically the only items that applications should need to reference, in order to parse and check tags. .. class:: Tag(interpreter, abi, platform) A representation of the tag triple for a wheel. Instances are considered immutable and thus are hashable. Equality checking is also supported. :param str interpreter: The interpreter name, e.g. ``"py"`` (see :attr:`INTERPRETER_SHORT_NAMES` for mapping well-known interpreter names to their short names). :param str abi: The ABI that a wheel supports, e.g. ``"cp37m"``. :param str platform: The OS/platform the wheel supports, e.g. ``"win_amd64"``. .. attribute:: interpreter The interpreter name. .. attribute:: abi The supported ABI. .. attribute:: platform The OS/platform. .. function:: parse_tag(tag) Parses the provided ``tag`` into a set of :class:`Tag` instances. Returning a set is required due to the possibility that the tag is a `compressed tag set`_, e.g. ``"py2.py3-none-any"`` which supports both Python 2 and Python 3. :param str tag: The tag to parse, e.g. ``"py3-none-any"``. .. function:: sys_tags(*, warn=False) Yields the tags that the running interpreter supports. The iterable is ordered so that the best-matching tag is first in the sequence. The exact preferential order to tags is interpreter-specific, but in general the tag importance is in the order of: 1. Interpreter 2. Platform 3. ABI This order is due to the fact that an ABI is inherently tied to the platform, but platform-specific code is not necessarily tied to the ABI. The interpreter is the most important tag as it dictates basic support for any wheel. The function returns an iterable in order to allow for the possible short-circuiting of tag generation if the entire sequence is not necessary and tag calculation happens to be expensive. :param bool warn: Whether warnings should be logged. Defaults to ``False``. .. versionchanged:: 21.3 Added the `pp3-none-any` tag (:issue:`311`). Low Level Interface ''''''''''''''''''' The following functions are low-level implementation details. They should typically not be needed in application code, unless the application has specialised requirements (for example, constructing sets of supported tags for environments other than the running interpreter). These functions capture the precise details of which environments support which tags. That information is not defined in the compatibility tag standards but is noted as being up to the implementation to provide. .. attribute:: INTERPRETER_SHORT_NAMES A dictionary mapping interpreter names to their `abbreviation codes`_ (e.g. ``"cpython"`` is ``"cp"``). All interpreter names are lower-case. .. function:: interpreter_name() Returns the running interpreter's name. This typically acts as the prefix to the :attr:`~Tag.interpreter` tag. .. function:: interpreter_version(*, warn=False) Returns the running interpreter's version. This typically acts as the suffix to the :attr:`~Tag.interpreter` tag. .. function:: mac_platforms(version=None, arch=None) Yields the :attr:`~Tag.platform` tags for macOS. :param tuple version: A two-item tuple presenting the version of macOS. Defaults to the current system's version. :param str arch: The CPU architecture. Defaults to the architecture of the current system, e.g. ``"x86_64"``. .. note:: Equivalent support for the other major platforms is purposefully not provided: - On Windows, platform compatibility is statically specified - On Linux, code must be run on the system itself to determine compatibility .. function:: platform_tags(version=None, arch=None) Yields the :attr:`~Tag.platform` tags for the running interpreter. .. function:: compatible_tags(python_version=None, interpreter=None, platforms=None) Yields the tags for an interpreter compatible with the Python version specified by ``python_version``. The specific tags generated are: - ``py*-none-`` - ``-none-any`` if ``interpreter`` is provided - ``py*-none-any`` :param Sequence python_version: A one- or two-item sequence representing the compatible version of Python. Defaults to ``sys.version_info[:2]``. :param str interpreter: The name of the interpreter (if known), e.g. ``"cp38"``. Defaults to the current interpreter. :param Iterable platforms: Iterable of compatible platforms. Defaults to the platforms compatible with the current system. .. function:: cpython_tags(python_version=None, abis=None, platforms=None, *, warn=False) Yields the tags for the CPython interpreter. The specific tags generated are: - ``cp--`` - ``cp-abi3-`` - ``cp-none-`` - ``cp-abi3-`` where "older version" is all older minor versions down to Python 3.2 (when ``abi3`` was introduced) If ``python_version`` only provides a major-only version then only user-provided ABIs via ``abis`` and the ``none`` ABI will be used. :param Sequence python_version: A one- or two-item sequence representing the targeted Python version. Defaults to ``sys.version_info[:2]``. :param Iterable abis: Iterable of compatible ABIs. Defaults to the ABIs compatible with the current system. :param Iterable platforms: Iterable of compatible platforms. Defaults to the platforms compatible with the current system. :param bool warn: Whether warnings should be logged. Defaults to ``False``. .. function:: generic_tags(interpreter=None, abis=None, platforms=None, *, warn=False) Yields the tags for an interpreter which requires no specialization. This function should be used if one of the other interpreter-specific functions provided by this module is not appropriate (i.e. not calculating tags for a CPython interpreter). The specific tags generated are: - ``--`` The ``"none"`` ABI will be added if it was not explicitly provided. :param str interpreter: The name of the interpreter. Defaults to being calculated. :param Iterable abis: Iterable of compatible ABIs. Defaults to the ABIs compatible with the current system. :param Iterable platforms: Iterable of compatible platforms. Defaults to the platforms compatible with the current system. :param bool warn: Whether warnings should be logged. Defaults to ``False``. .. _`abbreviation codes`: https://www.python.org/dev/peps/pep-0425/#python-tag .. _`compressed tag set`: https://www.python.org/dev/peps/pep-0425/#compressed-tag-sets .. _`platform compatibility tags`: https://packaging.python.org/specifications/platform-compatibility-tags/