Migration sections to categories: how to create index pages?

[DietmarSchwertberger]

I' migrating the wxPython site from Nikola 7 to 8 (triggered by the accessibilty problem, see other discussion).
The sections 'news' and 'blog' are now categories and their pages per entry are the same as before.

I'm missing the index[...].html pages, though.
This screenshot is from the old version:

How can I get these files again? I would guess that in 7 the relevant config option was POSTS_SECTIONS = True, but I can't test this as I could not get 7 to run. In 8 I can't see any option that looks similar.

I have tried CATEGORY_PAGES_ARE_INDEXES = True, which will create the required pages, but only in output/categories/cat_news, not in output/news.

[DietmarSchwertberger]

Some relevant(?) snippets:

From conf.py:

CATEGORY_DESCRIPTIONS = {
    DEFAULT_LANG: {
        'news': 'wxPython News',
        'blog': "wxForty-Two, a.k.a Robin's Ramblings"
    },
}

An example header from a news post "posts/news/2018-06-25-wxpython-4.0.3-release.md"

<!--
.. title: wxPython 4.0.3 Released
.. slug: wxpython-4.0.3-release
.. date: 2018-06-25 20:00:00 UTC-07:00
.. tags: Development, Release, Phoenix
.. category: News
.. link: 
.. description: 
.. type: text
-->

[DietmarSchwertberger]

No idea anyone?

[Kwpolska]

I have tried CATEGORY_PAGES_ARE_INDEXES = True, which will create the required pages, but only in output/categories/cat_news, not in output/news.

You should also adjust the two settings that are responsible for those paths (set both to ""):

CATEGORY_PATH = "categories"
CATEGORY_PREFIX = "cat_"

[DietmarSchwertberger]

Thanks, but that does not seem to work.
All these settings

CATEGORY_PATH = ""
CATEGORY_PREFIX = ""

CATEGORY_PATH = ""
CATEGORY_PREFIX = "cat_"

CATEGORY_PATH = "."
CATEGORY_PREFIX = ""

result in:

ERROR: Two different tasks can't have a common target.'output\index.html' is a target for render_taxonomies:output\index.html and render_pages:output\index.html.

It seems that with an empty path also the prefix and category are ignored.

[Kwpolska]

Try setting CATEGORIES_INDEX_PATH = "categories.html" to resolve the conflict.

[DietmarSchwertberger]

Thanks. That did work.
I had to stick to the bootstrap3 theme as base, as with bootstrap4 the navigation popups were not correct:

vs.

The only remaining difference is e.g. "1 Comments" vs. "Comments", but I think we can live with that.
Thanks a lot. A migration assistant would be helpful for the next major version change.