Discover and load entry points from installed packages.
This package is in maintenance-only mode. New code should use the
importlib.metadata module <https://docs.python.org/3/library/importlib.metadata.html>
_
in the Python standard library to find and load entry points.
Entry points are a way for Python packages to advertise objects with some
common interface. The most common examples are console_scripts
entry points,
which define shell commands by identifying a Python function to run.
Groups of entry points, such as console_scripts
, point to objects with
similar interfaces. An application might use a group to find its plugins, or
multiple groups if it has different kinds of plugins.
The entrypoints module contains functions to find and load entry points.
You can install it from PyPI with pip install entrypoints
.
To advertise entry points when distributing a package, see
entry_points in the Python Packaging User Guide <https://packaging.python.org/guides/distributing-packages-using-setuptools/#entry-points>
_.
The pkg_resources
module distributed with setuptools
provides a way to
discover entrypoints as well, but it contains other functionality unrelated to
entrypoint discovery, and it does a lot of work at import time. Merely
importing pkg_resources
causes it to scan the files of all installed
packages. Thus, in environments where a large number of packages are installed,
importing pkg_resources
can be very slow (several seconds).
By contrast, entrypoints
is focused solely on entrypoint discovery and it
is faster. Importing entrypoints
does not scan anything, and getting a
given entrypoint group performs a more focused scan.
When there are multiple versions of the same distribution in different
directories on sys.path
, entrypoints
follows the rule that the first
one wins. In most cases, this follows the logic of imports. Similarly,
Entrypoints relies on pip
to ensure that only one .dist-info
or
.egg-info
directory exists for each installed package. There is no reliable
way to pick which of several .dist-info
folders accurately relates to the
importable modules.