Content locking, or other solution for concurrent editing?

[jessesheidlower]

I'm trying to find a way to deal with the danger of concurrent editing, and I don't see any discussion of this here, or on Reddit or Stack Overflow.

Currently it seems that multiple people can edit the same entry at the same time, and this is not only prevented, but it's not even acknowledged in any way; the last edit wins, and no one else even knows that their change got clobbered. I'm not looking for a versioning system, which would be more complicated, just a way to prevent or at least warn about this.

Is there any solution or at least discussion of this anywhere? It would seem to be a pretty basic problem for any site that has more than one admin user.

[samuelhwilliams]

SQLAlchemy's version counter would be one way to fix this for individual models and SQLAlchemy only (obviously).

One approach Flask-Admin could take is to render all visible inputs with a hidden equivalent under some kind of original_ input prefix. Then Flask-Admin could assert that the record being edited still has that same set of data in before doing an overwrite, and flagging a warning/error if there is a difference.

This is probably quite a chunky piece of work, but it does feel like it would be valuable.

[ElLorans]

One approach Flask-Admin could take is to render all visible inputs with a hidden equivalent under some kind of original_ input prefix. Then Flask-Admin could assert that the record being edited still has that same set of data in before doing an overwrite, and flagging a warning/error if there is a difference.

This is probably quite a chunky piece of work, but it does feel like it would be valuable.

What if the value in a column excluded by flask-admin's view has been changed? In that case, we would keep both flask-admin's edits and the ones done on excluded columns, even if the data could be incompatible.

SQLAlchemy's version counter would be one way to fix this for individual models and SQLAlchemy only (obviously).

This looks to me like the best solution, especially because this looks like more of a job for the ORM than for flask-admin. We can try working on it and add an example.

[samuelhwilliams]

What if the value in a column excluded by flask-admin's view has been changed? In that case, we would keep both flask-admin's edits and the ones done on excluded columns, even if the data could be incompatible.

Yep, lots of scope and edge cases to think about if we try to take on that functionality 👍