Stabilize pip index

[sigma67]

What's the problem this feature will solve?

pip index has been marked experimental for two years now. It would be great if the interface could be stabilized for usage by external tools.

Describe the solution you'd like

Stabilize the command. I'm willing to help with any outstanding issues.

Alternative Solutions

not relevant

Additional context

I haven't managed to find any tickets regarding stabilization or a path forward for this feature, so I created this one. Feel free to point me there if there are any.

Related issues I found:

• Improve 'pip index versions' output to explain why it does not some versions visible on PyPI #10052
• programmatically convenient output of pip index versions #10983

Code of Conduct

• I agree to follow the PSF Code of Conduct.

[wimglenn]

The subcommand will also need to be documented, it's missing from https://pip.pypa.io/en/stable/cli/
It was added 2021-07-24 so docs are well overdue, even if it's documented as "experimental"

[sigma67]

@wimglenn could you create a tracking issue for the documentation? I will add it to the issue

[sigma67]

Albeit the linked issues are not dealt with, I will close this, as pip index was marked as not experimental without fixing those.

[notatallshaw]

Thanks for notiucing @sigma67, also there is now a json output to index: #13194. I've gone ahead and closed that issue.