entrypoints.rst

Entry points

.. todo::

   - Give an example of a custom entry point
     - Mention pluggy maybe for an example use-case?

Introduction

Entry points provide a mechanism to advertise components of an installed distribution to other code or users. There are three type of entry-points: those that provide commands to execute in a shell (project.scripts), commands to launch a GUI (project.gui-scripts), and discoverable (plugin style) entry-points (project.entry-points.<name>).

See the PyPA documentation on entry points.

Using entry points with meson-python

Entry points are defined in the pyproject.toml metadata specification. No further configuration is required when using meson-python.

Console entry point

To show the usage of console entry points we build a simple python script that simply prints the arguments it was called with:

 """
 Simple test application. Just prints the arguments.
 """


 import argparse


 def main():
     parser = argparse.ArgumentParser(prog='simpleapp', description=__doc__)
     parser.add_argument('doc', action='store_true')

     args = parser.parse_args()

     # Just print the arguments for now.
     print(args)


 if __name__ == "__main__":
     main()

This script will be part of a larger python package (called simpleapp). The meson build file is very simple and only installs the python sources.

 project('simpleapp', version:'0.0.1')


 py = import('python').find_installation('python3')
 py_dep = py.dependency()

 py.install_sources(
   ['src/simpleapp/__init__.py', 'src/simpleapp/console.py']
   , subdir: 'simpleapp'
 )

The entry points are then specified in the pyproject.toml metadata specification.

 [project]
 name = "simpleapp"
 description = "simple app"
 requires-python = ">=3.6"
 version = "0.0.1"

 [build-system]
 build-backend = 'mesonpy'
 requires = ["meson-python"]

 [project.scripts]
 simpleapp = "simpleapp.console:main"

PyInstaller Entry Point

To provide a PyInstaller entry point, add a pyinstaller hook directory containing at least a hook file:

 """
 This is a stub for a PyInstaller hook.
 """

 print("You discovered the PyInstaller plugin for simpleapp")

This sub-package must be added to the main package:

 ...
 py.install_sources(
   ['src/simpleapp/_pyinstaller/__init__.py', 'src/simpleapp/_pyinstaller/hook-simpleapp.py']
   , subdir: 'simpleapp/_pyinstaller'
 )

Then, the entry point can be defined in the project metadata: