Check for required extension module "ssl" in python3 build and spkg-configure

[mkoeppe]

Follow up from #27705.

As openssl has been a standard package since Sage 9.3, there is no more point in accepting system python3 without ssl support or ignoring errors in building the ssl module when building the python3 spkg.

As SSL issues are no longer a likely diagnosis for failures with launching the notebook, we change the corresponding code in src/bin/sage-notebook. (Prompted by ​https://groups.google.com/g/sage-devel/c/IXypXTbVkDM/m/CsWl8HbZAwAJ)

[gh-Shlokatadistance]

Can this also work with certifi package? I had issues previously with some other packages on Mac, and certifi seemed to fix it

[mkoeppe]

pushing these forward to 9.2

[mkoeppe]

Setting new milestone based on a cursory review of ticket status, priority, and last modification date.

[mkoeppe]

New commits:

​b6c27a7

build/pkgs/python3/{spkg-configure.m4,spkg-build.in}: Ensure ssl module is present

[git]

Branch pushed to git repo; I updated commit sha1. New commits:

​fa75b3e

src/bin/sage-notebook: On failures to import notebook/jupyterlab modules, point to instructions; do not offer a guessed diagnosis

[slelievre]

In build/pkgs/python3/spkg-build.in, line 32, the (preexisting) typo explicitely -> explicitly could be fixed since we're editing that file.

Any suggestions on how to review this ticket?

[jhpalmieri]

Replying to slelievre:

In build/pkgs/python3/spkg-build.in, line 32, the (preexisting) typo explicitely -> explicitly could be fixed since we're editing that file.

Any suggestions on how to review this ticket?

I guess if we can't find systems without the Python module ssl already installed, maybe we should just merge it and move on?

[mkoeppe]

Right, I'm not aware of a distribution whose python would be missing the ssl module. The new configuration tests here on the ticket protect against broken pythons compiled by users. The most likely scenario could be that a user configures the source from within the sage -sh of some old installation of Sage. Probably not useful to replicate something like this in order to review the ticket.

[jhpalmieri]

Why not just remove PREREQUISITE_ERROR completely?

[git]

Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:

​1fc8732	build/pkgs/python3/{spkg-configure.m4,spkg-build.in}: Ensure ssl module is present
​42489c1	src/bin/sage-notebook: On failures to import notebook/jupyterlab modules, point to instructions; do not offer a guessed diagnosis
​789c960	src/bin/sage-notebook: Remove PREREQUISITE_ERROR completely

[jhpalmieri]

This works for me, but my Python isn't broken (nor do I want to build a broken one), so I can't test the error messages. The code all makes sense, though.