they're no longer necessary for us and will almost definitely start to
rot now (like commonmark and asciidoc outputs did previously). most
existing users seem to take the docbook output and run it through pandoc
to generate html, those can easily migrate to use commonmark instead.
other users will hopefully pipe up when they notice that things they rely
on are going away.
optionsUsedDocbook has only been around for one release and only exposed
to allow other places to generate warnings, so that does not deserve
such precautions.
it's been long in the making, and with 23.05 out we can finally disable
docbook option docs and default to markdown instead. this brings a
massive speed boost in manual and manpage builds, so much so that we may
consider enabling user module documentation by default.
we don't remove the docbook support code entirely yet because it's a lot
all over, and probably better removed in multiple separate changes.
epub manuals are holding back the transition away from docbook, and
cursory research does not suggest that they are used very much. it's
still very early in the 23.11 release cycle, so if we're going to find
out just how many people do use the epub manuals it should be now.
this need not be the end of epub manuals. nixos-render-docs could be
extended to also export epubs, but that has not been done yet since it's
going to be some effort with unknown real-world usefulness.
The nixos/caddy module is somewhat old by now
and has undergone quite some refactors.
This specific module option (originally named
`ca`) used to make a bit more sense when
Caddy did not have multiple ACME CAs as
fallback (LE & ZeroSSL) by configured by
default yet (ZeroSSL came with v2.3.0).
I also rephrased the description slightly,
to mention Caddy's automatic issuer fallback
and a note which this option maps to in the
Caddyfile, to provide a bit more context and
a more up-to-date recommendation.
Specifically that "fine-grained configuration"
section comes from a time when this module did
some custom tls/issuer config json merging
with the templated Caddyfile using `jq`.
The "The URL to the ACME CA's directory"
section is a word-for-word copy from the
official Caddy docs, which also include a link
to LE's docs to the referenced staging
endpoint. So I added that as well.
