Prevent update conflicts (two automated processes acting on the same record)

Problem statement
In FOLIO, most storage modules follow the "last writer wins" strategy for handling record updates. From the UI perspective this may lead to a situation when a stale record (older version of a give record) previously loaded into the UI may override a more recent version on the server. Hence relevant updates may get lost in the process and the user is not made aware of what has happened.

This situation can happen when multiple data imports are happening at the same time (or data import and a user acting on the same record at the same time) and can affect many records at the same time. Cleanup can then be very time-consuming and confusing.

Proposed solution
From the storage and API perspective, optimistic locking is the proposed strategy to handle conflicts. Handling of updates in FOLIO should rely on more explicit semantics, both in the storage (backend) APIs and the way it is communicated to the user through the UI.

Use cases:
Two automated processes acting on the same record.

• Checkout happening and updating status on an item record at the same time as import updating the item

• Data import happening at 2 libraries within the same tenant, affecting the same record (e.g. 5 Colleges processing new cataloging records)

User impact

1. prevent collisions?

2. notify the user when they happen and offer them a choice? Something like, "Sorry AgentB has already updated the record and your working copy might not be up-to-date? Would you like to:" (a) Update anyway (b) Reload.