Recommended installation approach broken on Alpine 3.19

[jnoordsij]

First of all, thanks for this amazingly useful piece of software!

In the documentation, the installation for Alpine without a virtualenv (see https://doc.courtbouillon.org/weasyprint/stable/first_steps.html#alpine-3-12) is no longer working with Alpine 3.19, as Python’s package directory is now marked as externally managed; see also https://www.alpinelinux.org/posts/Alpine-3.19.0-released.html.

$ docker container run --rm alpine:3.19 /bin/sh -c "apk --no-cache add py3-pip py3-pillow py3-cffi py3-brotli gcc musl-dev python3-dev pango && pip3 --no-cache-dir install weasyprint"
...
error: externally-managed-environment

× This environment is externally managed
╰─>
    The system-wide python installation should be maintained using the system
    package manager (apk) only.

    If the package in question is not packaged already (and hence installable via
    "apk add py3-somepackage"), please consider installing it inside a virtual
    environment, e.g.:

    python3 -m venv /path/to/venv
    . /path/to/venv/bin/activate
    pip install mypackage

    To exit the virtual environment, run:

    deactivate

    The virtual environment is not deleted, and can be re-entered by re-sourcing
    the activate file.

    To automatically manage virtual environments, consider using pipx (from the
    pipx package).

note: If you believe this is a mistake, please contact your Python installation or OS distribution provider. You can override this, at the risk of breaking your Python installation or OS, by passing --break-system-packages.
hint: See PEP 668 for the detailed specification.

Possible solutions to fix the documentation:

• point towards the version available through apk
• update the installation suggestion to use pipx
• note that for Alpine >= 3.19 installation without virtualenv is not supported

[liZe]

Hi!

First of all, thanks for this amazingly useful piece of software!

You’re welcome!

In the documentation, the installation for Alpine without a virtualenv […] is no longer working with Alpine 3.19

Maybe we should remove the sections to install WeasyPrint with no virtualenv for all the distributions.

There’s a paragraph above, in the documentation, asking users to use the distribution’s package if possible, and to use a virtualenv otherwise. But you’re right, it’s not obvious when you reach directly a section for a given distribution.

What we should do is:

1. remove the "install with no virtualenv" section for all distirbutions,
2. replace it by a "To install WeasyPrint using your distribution’s package" with the related command line.

What do you think of that? Interested in opening a PR? 😄

[jnoordsij]

That sounds like a very reasonable approach. I'll see if I can manage to create a PR somewhere in the next few weeks!