Move scripts to Synapse package and expose as `entry_point`s; add suffices to scripts-dev

[DMRobertson]

black and flake8 will ignore such files by default. flake8 has a filename config option, but I haven't been able to use this to have flake8 run over the scripts it would otherwise script.

mypy does not have this problem: one can specify an explicit list of files to example or ignore. isort doesn't have such configuration, but does look for shebang lines to detect python scripts without a .py suffix.

Given a magic wand, I would like to:

• rename all scripts to end in .py
• change the documentation to include the new .py suffix
• change the debian package build so that the new scripts are available by the old, suffixless filename

Bullet three here is the hard one.

This would allow me to run black . and flake8 . both locally and in CI without thinking.

[DMRobertson]

• change the debian package build so that the new scripts are available by the old, suffixless filename

Bullet three here is the hard one.

Aha! This is done in matrix-synapse-py3.links.

[richvdh]

I am not enthusiastic about naming commands according to the language they happen to be written in. It feels a bit like Hungarian notation. Linux prefers #! lines over file extensions for a reason.

However, Setuptools allows an entry point to be defined in a file named *.py and still get installed into the virtualenv with its regular name - see https://setuptools.pypa.io/en/latest/userguide/entry_point.html.

It looks like poetry's scripts do much the same thing.

[DMRobertson]

An alternative would be to keep passing around the list of explicit targets to lint, both in CI and in lint.sh. That's fine and is probably easier---but it would mean maintaining duplicate lists, which is the kind of thing I'm trying to move us away from with poetry.

On entry_points and scripts: I'm glad you brought that up. When I looked at register_new_matrix_user I thought "this could just be an entry point".

synapse/scripts/register_new_matrix_user

Lines 16 to 19 in 4b965c8

	from synapse._scripts.register_new_matrix_user import main
	if __name__ == "__main__":
	main()

I think this script was moved to within Synapse (#4085) in order to be tested here:

synapse/tests/scripts/test_new_matrix_user.py

Line 17 in 4b965c8

from synapse._scripts.register_new_matrix_user import request_registration

How would you feel about migrating the scripts' source code to synapse._scripts and exposing them as entry_points? It'd be useful for #11537, because I don't think poetry's config will offer me a way to glob within the scripts directory like we have at present:

synapse/setup.py

Line 169 in e6acd3c

scripts=["synctl"] + glob.glob("scripts/*"),

[richvdh]

How would you feel about migrating the scripts' source code to synapse._scripts and exposing them as entry_points?

sgtm

[DMRobertson]

In addition to #12118 I need to do this for synctl.

I'd also like to add the .py suffix within scripts-dev. I sympathise with "things to be executed shouldn't have a suffix", but

• we're not distributing those scripts with installations
• most of them have a suffix anyway
• it will let me prune a lot of boring CI config

[richvdh]

yeah I'm less fussed about scripts-dev. It's a hodgepodge of "expert" stuff anyway.

[richvdh]

@DMRobertson can we call this done?

[DMRobertson]

Yes. I think it just didn't get closed because the PR was targetted at a release branch.