Fast entry_points
=================
Using ``entry_points`` in your setup.py makes scripts that start really
slowly because it imports ``pkg_resources``, which is a horrible thing
to do if you want your trivial script to execute more or less instantly.
check it out: https://github.com/pypa/setuptools/issues/510
importing ``fastentrypoints`` in your setup.py file produces scripts
that look like this:
.. code:: python
# -*- coding: utf-8 -*-
import re
import sys
from package.module import entry_function
if __name__ == '__main__':
sys.argv[0] = re.sub(r'(-script\.pyw?|\.exe)?$', '', sys.argv[0])
sys.exit(entry_function())
This is ripped directly from the way wheels do it and is faster than
whatever the heck the normal console scripts do.
Note:
This bug in setuptools only affects packages built with the normal
setup.py method. Building wheels avoids the problem and has many other
benefits as well. ``fastentrypoints`` simply ensures that your user
scripts will not automatically import pkg_resources, no matter how
they are built.
Usage
-----
To use fastentrypoints, simply copy fastentrypoints.py into your project
folder in the same directory as setup.py, and ``import fastentrypoints``
in your setup.py file. This monkey-patches
``setuptools.command.easy_install.ScriptWriter.get_args()`` in the
background, which in turn produces simple entry scripts (like the one
above) when you install the package.
If you install fastentrypoints as a module, you have the ``fastep``
executable, which will copy fastentrypoints.py into the working
directory (or into a list of directories you give it as arguments) and
append ``include fastentrypoints.py`` to the MANIFEST.in file, and
add an import statement to setup.py. It is available from PyPI.
You can't really make it a proper dependency because setuptools has to
import it to work, so chicken-egg. right? Luckily, the script is trivial
and will not hurt you project much to copy this 60-line file into the
folder. Be sure to add it to MANIFEST.ini if you want to distributie it
on PyPI.
Alternatively, if you don't want to vendor the code, it is possible to
install it from pypi with easy_install in the setup script:
.. code:: python
try:
import fastentrypoints
except ImportError:
from setuptools.command import easy_install
import pkg_resources
easy_install.main(['fastentrypoints'])
pkg_resources.require('fastentrypoints')
import fastentrypoint
Let me know if there are places where this doesn't work well. I've
mostly tested it with ``console_scripts`` so far, since I don't write
the other thing.
