org-publish: Best practice to generate a html header on a per-file basis ?

[Sander Boer <sanboer@gmail.com>]

Hi all,

I've been investigating a viable way to generate for every exported html file in an org-publish project a list of links to all the other html files in the directory-tree and I'm stuck.
I want this list to be inserted as a header, nicely css-ed into a navigation bar.

The idea is to graft a function that is either passed to :html-preamble or is added as a hook to org-export-html-final-hook.
Incidently, it took a long time to figure out that one cannot pass mere functions to html-preamble like this:
:html-preamble 'my-cool-function-that-returns-a-string
nor like this:
:html-preamble 'my-cool-function-that-*inserts*-a-string

instead it needs to be:
:html-preamble (lambda(x) (insert (my-cool-function-that-returns-a-string x)))
or,
:html-preamble (lambda(x) (my-cool-function-that-inserts-a-string x))


Anyway, with that out of the way, now I am left with the challenge of figuring out how to determine the position of this file with regard to the other files in the project, file-relative-name really comes in handy here. The issue for me is that the html-preamble and the ....-final-hook are called in the html buffer. It is easier to graft a link list based on the original org-tree than on the exported html-tree, as path-changes would cause issues.
So the idea is now to find the path to the original org-file and construct a link list based on the original org-publish tree (cunningly renaming .org into .html)
Alternatively, how about extending the sitemap generator to generate a link-list for every file like so:
file.org-> file.inc file.html
file.inc would only consist of:
<div id="linklist">
<a href=../projects/randomproject.html>cool project</a>
<a href=../contact/about.html>all me</a>
<a href=../../index.html>home</a>
</div>
(hmm bad example, it also needs some form of ul/li grouping based on subdirectory, but you get the idea)

Any and all tips and pointers are appreciated.

sndr