[Pmwiki-users] Feature-request: deleting revisions

[Patrick R. Michaud]

On Thu, May 13, 2004 at 12:25:36PM +0200, Thomas -Balu- Walter wrote:
> 
> Reverting those changes will not help as they will still be listed in
> the revisions. So I (admin) need a feature to completely remove edits
> from the page AND from the revisions.

Yes, they still appear in the revisions, but the output of page
revisions normally contains a <meta> tag with 'noindex,nofollow',
so any reputable search engine shouldn't index those.  Of course,
the wiki spammers may not realize this (or care), so...

As Gregory Watts already mentioned, there's the ExpireDiff script
in the Cookbook which can be used to eliminate all of a page's revisions.  
(It actually saves a copy of the page history in wiki.d if you
need it, though, same as the "delete" command.) However, if you 
need the ability to expire a single page revision while leaving 
the others intact...well, things get slightly more complex...

We can't just simply physically remove a revision from the page
history, because it's needed in order to reach earlier versions of
the page.  Like CVS, PmWiki doesn't store complete copies of each
version of a page, it only stores the differences need to get
from the current version to the previous one.  Remove one of the
revisions from the chain, and you lose the ability to get to any
of the versions prior to that.

One could see about generating a whole new revision history that
excludes the unwanted revision, but perhaps a simpler option would
be to make it possible for admins to selectively suppress the
display of certain revisions in the history.  As it is now, each
revision can be marked as being a "minor" revision, but I left
this feature extensible so that other flags could be added.  So,
perhaps we can add an (admin?) option somewhere to allow 
revisions to be flagged as one of major, minor, or hidden.

I'm having similar problems with wikispam on my system, as you
may have noticed.  But I figure that the fact that links appear
in the page history isn't doing the spammers much good because
of the meta tag.  My next approach is going to be to create a 
"blacklist.php" module so that an admin can identify IP ranges 
(and possibly domains) from which all posts should be blocked.

Reactions, comments?

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