[[!tag patch wishlist]]I quite often find myself repeating a boiler-plate
-pagespec chunk, e.g.
+[[ikiwiki/pagespec]] chunk, e.g.
and !*.png and !*.jpg...
not sure whether I should name-grab 'alias' since [[todo/alias_directive]] is
an existing wishlist item.
+> I think it would make sense to have "pagespec" in the name somehow.
+
+> > Good idea, how about `pagespecalias`? — [[Jon]]
+
+>
+> No, the strict/warnings does not make me puke. Have you read my perl
+> code? :-P
+>
+> Note that your XXX is right. It would be a security hole to not validate
+> `$key`, as anyone with websetup access could cause it to run arbitrary
+> perl code.
+>
+> Well, except that websetup doesn't currently support configuring hashes
+> like used here. Which is a pity, but has led me to try to avoid using
+> such hashes in the setup file.
+
+> > If I removed the `getsetup` subroutine, it would not be exposed via
+> > website, is that right? I suppose it doesn't hurt to validate key, even if
+> > this risk was not there. Is the use of a hash here a blocker for adoption?
+> > — [[Jon]]
+
+> Have you considered not defining the pagespec aliases in the setup file, but
+> instead as directives on pages in the wiki? Using pagestate could store
+> up the aliases that have been defined. It could however, be hard to get
+> the dependencies right; any page that uses a pagespec containing
+> an alias `foo` would need to somehow depend on the page where the alias
+> was defined. --[[Joey]]
+
+> > I haven't thought the dependency issue through beyond "that might be hard".
+> > Personally, I don't like defining stuff like this in pages, but I appreciate
+> > some do. There could be some complex scenarios where some pages rely on a
+> > pagespec alias defined on others; and could have their meanings changed by
+> > changing the definition. A user might have permission to edit a page with a
+> > definition on it but not on the pages that use it, and similar subtle permission
+> > bugs. I'm also not sure what the failure mode is if someone redefines an alias,
+> > and whether there'd be an unpredictable precedence problem.
+> > How about both methods? — [[Jon]]
+
Here's an example setup chunk:
pagespec_aliases:
however, to add ' or internal()' to `boring`, for some reason.
-- [[Jon]]
+
+> Probably needs to be `or internal(*)` --[[Joey]]
+
+> > Ah yes, could be, thanks. — [[Jon]]
+
+> another useful pagespec alias for large maps:
+
+ basewiki: "sandbox or templates or templates/* or ikiwiki or ikiwiki/* or shortcuts or recentchanges or wikiicons/*"
+
+> -- [[Jon]]
+
+>> Useful indeed! --[[Joey]]
+
+---------------------------
+
+Based on the above, I have written an experimental plugin called "subset".
+It's in my "ikiplugins" repo on github, in the "experimental" branch.
+<https://github.com/rubykat/ikiplugins/blob/experimental/IkiWiki/Plugin/subset.pm>
+
+It takes Joey's suggestion of defining the subsets (aliases) as directives;
+I took the example of the [[plugins/shortcut]] plugin and designated a single special page as the one where the directives are defined,
+though unlike "shortcut" I haven't hardcoded the name of the page; it defaults to "subsets" but it can be re-defined in the config.
+
+I've also added a feature which one might call subset-caching; I had to override `pagespec_match_list` to do it, however.
+An extra parameter added to `pagespec_match_list` called `subset` which
+
+* limits the result to look *only* within the set of pages defined by the subset (uses the "list" option to pagespec_match_list to do this)
+* caches the result of the subset search so that the second time subset "foo" is used, it uses the stored result of the first search for "foo".
+
+This speeds things up if one is using a particular subset more than once, which one probably is if one bothered to define the subset in the first place.
+The speed increase is most dramatic when the site has a large number of pages and the number of pages in the subset is small.
+(this is similar to the "trail" concept I used in my [[plugins/contrib/report]] plugin, but not quite the same)
+
+Note that things like [[plugins/map]] can't make use of "subset" (yet) because they don't pass along all the parameters they're given.
+But [[plugins/contrib/report]] actually works without alteration because it does pass along all the parameters.
+
+Unfortunately I haven't figured out how to do the dependencies - I'd really appreciate help on that.
+
+--[[KathrynAndersen]]
+
+> > Cool! I like the caching idea. I'm not sure about the name. I don't like defining
+> > stuff in pages, but I appreciate this is a matter of taste, and would be happy with
+> > supporting both. — [[Jon]]
+
+>>> I've now gone and completely re-done "subset" so that it is less like an alias, but it a bit clearer and simpler:
+>>> instead of having a separate "match_" function for every alias, I simply have one function, "match_subset"
+>>> which takes the name of the subset. Thus a \[[!subset name="foo"...]] would be called `subset(foo)` rather than `foo()`.
+
+>>> There are a few reasons for this:<br/>
+>>> (a) it's more secure not to be evaluating code on the fly<br/>
+>>> (b) it's simpler<br/>
+>>> (c) (and this was my main reason) it makes it possible to do caching without having to have a separate "subset" argument.
+>>> I've done a bit of a hack for this: basically, the PageSpec is checked to see if the very start of the PageSpec is `subset(foo) and` or if the whole pagespec is just `subset(foo)` and if either of those is true, then it does the subset caching stuff.
+>>> The reason I check for "and" is that if it is "subset(foo) or something" then it would be an error to use the subset cache in that case.
+>>> The reason I just check the start of the PageSpec is because I don't want to have to do complex parsing of the PageSpec.
+
+>>> As for defining subsets in the config rather than on pages, I perfectly understand that desire, and I could probably add that in.
+
+>>> As for the name "subset"... well, it's even less like an alias now, and "alias" is already a reserved name. What other names would you suggest?
+
+>>>--[[KathrynAndersen]]
sipb-www / ikiwiki.git / blobdiff