On [[todo/auto-create_tag_pages_according_to_a_template]], [[chrysn]]
suggests:
Instead of creating a file that gets checked in into the RCS, the
source files could be left out and the output files be written as
long as there is no physical source file (think of a virtual underlay).
Something similar would be required to implement alias directive,
which couldn't be easily done by writing to the RCS as the page's
contents can change depending on which other pages claim it as an alias.
add_autofile could be adapted to do this, or a similar API could be
added.
This would also be useful for autoindex, as suggested on
[[plugins/autoindex/discussion]]. I'd also like to use it for
[[plugins/contrib/album]].
One refinement I'd suggest is that if the transient page is edited,
its transient contents are evaluated and used as the initial
content for the edit box; after that, it'd become a static page. --[[smcv]]
[[!template id=gitbranch branch=smcv/ready/transient author="[[smcv]]"]]
[[!tag patch]]
I think this branch is now enough to be useful. It adds the following:
If the transient plugin is loaded, $srcdir/.ikiwiki/transient is added
as an underlay. I'm not sure whether this should be a plugin or core, so
I erred on the side of more plugins; I think it's "on the edge of the core",
like goto.
Pages with the default extension in the transient underlay are automatically
deleted if a page of the same name is created in the srcdir (or an underlay
closer to the srcdir in stacking order).
tag enables transient, and if tag_autocreate_commit is set to 0
(default 1), autocreated tags are written to the transient underlay.
There is a regression test.
autoindex uses autofiles. It also enables transient, and if
autoindex_commit is set to 0 (default 1), autoindexes are written to
the transient underlay. There is a regression test.
autoindex ignores pages in the transient underlay when deciding whether
to generate an index.
New recent changes go in the transient underlay; I tested this manually.
Not done yet (in that branch, at least):
-
remove can't remove transient pages: this turns out to be harder than
I'd hoped, because I don't want to introduce a vulnerability in the
non-regular-file detection, so I'd rather defer that.
-
Transient tags that don't match any pages aren't deleted: I'm not sure
that that's a good idea anyway, though. Similarly, transient autoindexes
of directories that become empty aren't deleted.
-
In my untested/transient branch, new aggregated files go in the
transient underlay too (they'll naturally migrate over time). I haven't
tested this yet, it's just a proof-of-concept.
I can confirm that the behavior of autoindex, at least, is excellent.
Haven't tried tag. Joey, can you merge transient and autoindex? --JoeRayhawk
An earlier version
I had a look at implementing this. It turns out to be harder than I thought
to have purely in-memory pages (several plugins want to be able to access the
source file as a file), but I did get this proof-of-concept branch
to write tag and autoindex pages into an underlay.
This loses the ability to delete the auto-created pages (although they don't
clutter up git this way, at least), and a lot of the code in autoindex is
probably now redundant, so this is probably not quite ready for merge, but
I'd welcome opinions.
Usage: set tag_underlay and/or autoindex_underlay to an absolute path,
which you must create beforehand. I suggest srcdir + /.ikiwiki/transient.
Refinements that could be made if this approach seems reasonable:
- make these options boolean, and have the path always be
.ikiwiki/transient
- improve the
remove plugin so it also deletes from this special underlay
Perhaps it should be something more generic, so that other plugins could use it (such as "album" mentioned above).
The .ikiwiki/transient would suit this, but instead of saying "tag_underlay" or "autoindex_underlay" have "use_transient_underlay" or something like that?
Or to make it more flexible, have just one option "transient_underlay" which is set to an absolute path, and if it is set, then one is using a transient-underlay.
--[[KathrynAndersen]]
What I had in mind was more like tag_autocreate_transient => 1 or
autoindex_transient => 1; you might conceivably want tags to be
checked in but autoindices to be transient, and it's fine for each
plugin to make its own decision. Going from that to one boolean
(or just always-transient if people don't think that's too
astonishing) would be trivial, though.
I don't think relocating the transient underlay really makes sense,
except for prototyping: you only want one, and .ikiwiki is as good
a place as any (ikiwiki already needs to be able to write there).
For [[plugins/contrib/album]] I think I'd just make the photo viewer
pages always-transient - you can always make a transient page
permanent by editing it, after all.
Do you think this approach has enough potential that I should
continue to hack on it? Any thoughts on the implementation? --[[smcv]]
Ah, now I understand what you're getting at. Yes, it makes sense to put transient pages under .ikiwiki.
I haven't looked at the code, but I'd be interested in seeing whether it's generic enough to be used by other plugins (such as album) without too much fuss.
The idea of a transient underlay gives us a desirable feature for free: that if someone edits the transient page, it is made permanent and added to the repository.
I think the tricky thing with removing these transient underlay pages is the question of how to prevent whatever auto-generated the pages in the first place from generating them again - or, conversely, how to force whatever auto-generated those pages to regenerate them if you've changed your mind.
I think you'd need something similar to will_render so that transient pages would be automatically removed if whatever auto-generated them is no longer around.
-- [[KathrynAndersen]]
