describe different persistance vs model update strategies

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Bruno Windels 2019-02-06 22:07:05 +00:00
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# persistance vs model update of a room
## persist first, return update object, update model with update object
-
## update model first, return update object, persist with update object
- not all models exist at all times (timeline only when room is "open"),
so model to create timeline update object might not exist for persistence need
## persist, update, each only based on sync data (independent of each other)
- possible inconsistency between syncing and loading from storage as they are different code paths
+ storage code remains very simple and focussed
## updating model and persisting in one go
- if updating model needs to do anything async, it needs to postpone it or the txn will be closed
## persist first, read from storage to update model
+ guaranteed consistency between what is on screen and in storage
- slower as we need to reread what was just synced every time (big accounts with frequent updates)