MoinMoin

> Hi, I'm trying to implement an exclusive page editing lock in MoinMoin. I
> tried doing this by adding "Locks" class to PageEditor. I maintain a file
> which lists pages that people started editing and don't allow people to edit
> files that are currently edited. There is also a timer (of one hour) which
> allows for the case where a page is opened for editing but noone saves it
> back for whatever reason (eg. close the browser, a crash, follow a link off
> site etc).

I is perhaps much easier to use lock files, perhaps
data/pages/QuotedPageName/edit.lck . File operations are atomic and
file have a modified time, which could be useful.

> It then occurred to me that I could to the edit locking through the Security
> Permissions in  the site config. I could override the edit check and lock a
> page when this first called, then unlock it when it is saved. Unfortunately
> I cant tell the difference between an edit query on beginning editing a
> page, a preview and a save.

You will have to modify PageEditor.send_editor and PageEditor.save_page.
All information metioned above is available in this method. I would not use
file permissions to block the page, but read the lock file in
PageEditor.send_editor. You may want to use
request.form['datestamp'].value which is the timestamp of the file that
was send for editing.

> I'd really not alter the Moin source extensively as I'd like to swap in new
> versions easily. I could use Permissions to do this is there was some sort
> of called to Permissions or callback for "edit page", "save page". If not
> done by overriding virtual methods here, how else might this be done?
>
> Has anyone else implemented this functionality? It could be extended to set
> permissions on individual pages eg. to set unreadable to certain people, or
> a certain times etc. Moin is an excellent wiki but people are complaining to
> me about losing their changes and don't want to do merging! I'd like to do
> this properly and perhaps I could feed it back to be integrated?

I doubt this is a feature many people will want to have in MoinMoin. (I
heard that some search engines like to try the edit URLs)
Perhaps it is more worth to put some work in collision resolving.

	cu

		Florian Festi

Nick,

Just thought I'd add my 2 cents to the discussion.

I agree with Florian that this is better handled with separate
lock files than with physical file locks.

I, for one, would be interested in this feature.  But maybe it would
be better to do something that was advisory rather than mandatory.
This can be important in the cases you mentioned where a an
edit was abandoned.  Having to wait for a lock to expire or
call on an administrator to break a lock would be a huge hassle.

I'd appreciate something as simple as a notice - before the page
edit came up (or at the top of the edit page) - that it appears
that someone is already editing the page (and maybe who it was). 
Then the user could decide if they wanted to continue (make
their edits and save) or not.

This should solve most of the collision problems, if the notice is
prominent enough and people pay attention to it.  What you're
really trying to fix is the very annoying situation where you've
spent a long time editing a page, only to find out someone has 
submitted data ahead of you, and now you have to reconcile the
two submissions.  In the case where someone started their edit
before you, you can be advised to wait until their done to start
your long edit.  In the case where someone starts their edit after
you, they can be advised that you are working on it, and back off
to let you finish.

If people consistently abandon edits midstream, that's a 
training problem, and if people ignore the warning about another
edit in progress, that's a social problem.  The final problem,
of someone being an "edit hog", is also a social problem, but
is present whether there's a locking system, notice system, or
even the current edit-at-will system.  Most wikis should have
such a problem!!  :^)

Just some thoughts...

Tim Bird

=====
Tim Bird 
Embedded Linux Consultant 
tim@... 

Tim Bird Consulting
801-221-5852
http://www.bird.org/

Hi Tim,

> I, for one, would be interested in this feature.  But maybe it would
> be better to do something that was advisory rather than mandatory.

Yes. That's more fault-tolerant.

Just say "this page is being edited since <timestamp of last user 
action> by <username>" in big red letters and let it to the user ...

greetings, Thomas