Concurrent content updates

[kieron-mcintyre]

I'm assuming that this has been discussed previously but I can't find mention of it in the repo, so apologies if this has already been raised.

One of my biggest bug bears with Umbraco is the fact that multiple editors can be editing the same content and the last one to save or publish their content will overwrite the changes of the other editors. Ideally this shouldn't be possible.

I would imagine the two potential approaches are:

• Pessimistic concurrency - Saving content creates a branch off the original content, allowing multiple concurrent saves to be made without a conflict. This has the obvious downside that multiple variants of content could then exist and a mechanism for realising a single version would/might have to exist.
• Optimistic concurrency - Saving content that has already been saved prevents the current save action and instead shows a warning that user X has edited the same content. An option would then be provided to reload the content with the latest changes or overwrite with your own.

(I think I got that the right way round ...)

Other things to consider are:

• Could it be possible to at least warn an editor that someone else is editing the page being browsed?
• Could a merge option be offered?
• Would being able to create branches of content actually be a great feature? I.e. where an editor wants to be able to prep 2 variants of the same page for A/B testing.