Override the display of node revisions (using Panels layouts)

I'd love this.
Would be particularly useful with modules such as workbench moderation, which is all about enabling revision-centric workflow.

The dev version has working panel view modes. Of course this is alpha code, now it's time to extend and refactor and add new features.

I've been wondering whether revisioning overrides isn't something for page manager itself. Of course, now it should be possible too. Just wondering which approach is best:

- separate view mode
- variant on the full/default panel view mode

Discuss!

You're right that it probably should be handled by page manager... I just dug through the issue queue a little and found this: #515518: Optional node revision task handler to override default behavior

That suggests that it should really be in there - but it got closed because the revisioning maintainer added it to that module instead of ctools.

EDIT: Oh, I forgot about the question you were raising.

I wonder if it'd be easier to simply be able to set revisions to display with the default/full view mode. That's the most likely use case.

Most of the time (I would say easily 80%+) you're going to want the revisions to display exactly as they do in the default/full view mode (panels-based or otherwise).

It would be cumbersome to have to recreate a view mode in order to achieve this.
That would be solved with Ben's suggestion of allowing cloning.

However, it occurs to me that simple solution (from the site builder's perspective, that is) that doesn't restrict flexibility would be an extension of the point I edited in to #3. If you could select a view mode for revisions to use, then it'd immediately solve the most common use case without any extra work but you'd still be free to use an alternative view mode (you might choose to build a custom revision one, for example).

@BenK Huh, I thought it had been implemented in the D6 version but not fully ported to D7.
One way or another I knew it wasn't available to us in D7 and certainly hadn't been done in ctools :)

Haven't had further thoughts about this right now. Frega is hacking into the admin interface right now to add contexts and selection rules, so I'm waiting what he comes up with first. We're sitting together next week at the designcamp and hopefully we can have a small sprint with some first good results.

Small follow up - cloning is supported so it's really easy to create new view modes. Now, the only way to find out if we're looking at a revision is apparently by looking at the path. There is no indication on the node object itself (unless I'm missing something). So it seems like the overriding would need to happen hardcoded. Using the contexts or selection rules is still far off (and rather heavy and difficult and adding some overhead as well).

There's another problem. The revisions callback calls node_show() which will render the node with the 'full' view mode, so no way to override that. Unless we take over the page callback and render this ourselves. This sounds like an 'extras' feature to me which I'm perfectly fine with. I'll start experimenting with this and post a patch so you guys can play with it.

Here's a patch to review. What it does:

- adds an extra option 'Revision view mode' on the Extras screen (in the other fieldset)
- adds an extra revision view mode which you can then style
- takes over the menu callback of a node revision view. It checks if revision view mode is configured and uses it than, otherwhise use full (which in that case would fallback to default).

This works both with field ui and panels layout editor.

Needs tests, but you can test the functionality on itself.

Updated patch which has tests as well.

Hrm I'll look into it, I thought the node was already passed in as a context, but could have been lost during refactoring.

Hey,

Works fine here - I'm using the views content panes modules which comes with CTools module, the view is configured using 'content: nid' as the argument, so not really an idea what might go wrong at your installation.

Cool, I'll commit this asap, changing the status to make sure I commit this tonight :)

Committed and pushed, thanks for testing and feedback!