Answering my own questions for googler's posterity, based on some initial experimentation and googling, corrections welcome.
> Is it possible to (manually or automatically) trigger a full rebuild of the 'relation' 'references'
These backlink structures are re-constructed automatically as individual pages are browsed, so you could use a spidering tool to bulk rebuild them, and it looks to me like running bin/indexer.php
from the CLI does the job, so presumably http://www.dokuwiki.org/plugin:searchindex
does as well.
All other data written to the /meta
folders, both by core and plugins, all seem to be similarly rebuilt from other sources,
> assuming this http://www.dokuwiki.org/devel:metadata
so at least as far as I'm concerned, there's nothing important lost by wiping it. Same goes for the index, presumably /tmp[/m] and for my use case, (warning - long! http://forum.dokuwiki.org/thread/7677), I personally don't care about revision history stored in [m]/attic
Therefore when I need to refactor my text files outside of DW - rename pages, rename/split/merge namespace/directories etc, it seems that from the /data
directory, I can just
sudo rm -rf attic/*
sudo rm -rf cache/*
sudo rm -rf index/*
sudo rm -rf meta/*
sudo rm -rf tmp/*
And I'll get a nice kruft-free DokuWiki instance containing nothing but my data files. Of course, as I try out the various cross-referencing/ToC/indexing etc tools, I may find problems, but my ability to freely refactor my data is important enough I'll probably only choose plugins/methods that work within this context.
So until DW officially supports the ability to easily rename page/files and namespace/folders within the UI, this seems to be a doable workaround **for me** - of course, my needs are certainly an edge case, I'm not advocating this for others etc etc.
And if any of you more knowledgeable folk out there have any comments on this, please speak up.