StaleObject Merging Example

Rails
1

Does anyone have an example of how they have dealt with
StaleObjectErrors caused by having optimistic locking enabled?

Ideally I’d like to merge the changes, but I haven’t found much in
terms of sample code or documentation on how to do this.

Any help would be appreciated.

Thanks.

  • j
2

Hi Justin

I’m interested in this as well. I discovered today that a project I’m
developing threw several StaleObject errors, after I got a report of
discrepancies in views of the data.

Aside…
I did not even bother writing code to catch the error, eventhough I
went to the trouble to add lock_version fields to all my tables. (I
even wrote a nice little piece of code that reads the schema and
creates lock_versions for all my tables. Got carried away I guess :^)
…Back.

I’m wondering how the data got stale. I’m certain the customer was the
only person updating the rows. However, I have a piece of code that
could be better written…

In the loop below, packing_item belongs_to rma and I do a separate
save on each table record. The error occurred on the second save. Can
this happen if only one person is running the application?

packing_slip.packing_items.each_with_index do |item, i|
  item.rma.state_id = PACKED

  item.rma.packing_slip_id = packing_slip.id

  item.rma.tracking_number = tracking[item.rma.number]

[:tracking_number]

  item.tracking_number = tracking[item.rma.number]

[:tracking_number]

  # save packing_item
  item.save!

  # save rma <-- the error happened at this point.
  item.rma.save!
end

Dave