bug#73425: 31.0.50; Support images in HTML versions of ELPA package manuals

[Philip Kaludercic <philipk@posteo.net>]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Philip Kaludercic <philipk@posteo.net>
>> Cc: Eshel Yaron <me@eshelyaron.com>,  73425@debbugs.gnu.org
>> Date: Sun, 22 Sep 2024 18:03:26 +0000
>> 
>> Eli Zaretskii <eliz@gnu.org> writes:
>> 
>> >> Cc: Philip Kaludercic <philipk@posteo.net>
>> >> Date: Sun, 22 Sep 2024 18:06:16 +0200
>> >> From:  Eshel Yaron via "Bug reports for GNU Emacs,
>> >>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
>> >> 
>> >> I'm opening this feature request following a discussion with Philip
>> >> elsewhere: Texinfo manual can include images, but AFAIK (and please
>> >> correct me if I'm wrong here) there's currently no way for ELPA packages
>> >> to include images in their manuals and have these images appear also in
>> >> the HTML version of the manual that the ELPA server builds and serves.
>> >
>> > Why "no way"?  If the image files are present at their filenames as
>> > mentioned by the HTML version of the documentation, they will be shown
>> > by the browser.
>> 
>> The issue is that when generating the HTML documentation for
>> elpa.gnu.org, we don't copy out any files, but just generate the HTML
>> version of the manual.
>> 
>> What we need is some kind of an indication in the package specification,
>> what files should be copied out for the manual to access, as otherwise
>> the images would only be hidden in the package tarball, that a web
>> browser cannot access (AFAIK).
>
> "Copied" where and why?  Aren't the HTML docs generated in the
> package's tree, like the Info docs?

No, these are the files we generate for a package under
https://elpa.gnu.org/packages:

  -rw-r--r--  1 phi phi 368640 Mar 22  2024 compat-29.1.4.5.tar
  -rw-r--r--  1 phi phi  11183 Mar 22  2024 compat.html
  -rw-r--r--  1 phi phi    997 Mar 22  2024 compat-readme.txt
  -rw-r--r--  1 phi phi   1230 Mar 22  2024 compat.svg
  lrwxrwxrwx  1 phi phi     19 Mar 22  2024 compat.tar -> compat-29.1.4.5.tar
  -rw-r--r--  1 phi phi   1016 Mar 22  2024 compat.xml

plus the manual under https://elpa.gnu.org/packages/doc/[package name]

  -rw-r--r--  1 phi phi 46640 Mar 21  2024 corfu.html

(there is another symlink to this file but that is not important now).
Other than that, no files are copied out.

>> >> - Include images in the package repository, somehow indicate in the
>> >>   package specification that the manual refers to these images, and have
>> >>   the ELPA server keep the images around in a predictable location, so I
>> >>   can link to it from the manual.
>> >
>> > I don't understand why this would be needed.  Simply include the image
>> > files with the package, and the rest should "just work", AFAIU.
>> 
>> Do you know if TeXinfo has an option to inline images?  If the
>> "makeinfo" command could somehow generate data: urls when exporting
>> images, then this could be very easily solved.
>
> This is already supported, for a long time, both in Info and HTML
> formats (and in other formats as well; see the node "Image Syntax" in
> the Texinfo manual.

I did take a look at that node, but I couldn't find anything that would
help me.

-- 
	Philip Kaludercic on siskin