openactive / realtime-paged-data-exchange

OpenActive Realtime Paged Data Exchange Specification
https://www.openactive.io/realtime-paged-data-exchange/
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Consumer never being able to catch up with feed #74

Open lukehesluke opened 7 years ago

lukehesluke commented 7 years ago

RE: section #4.2 bullet points #2,3: "Records can freely move position in the list as they are updated"

This concept of storing only one entry for each item is very simple to implement for a data provider and I appreciate that that is very important in keeping the barrier to entry low

However, if a number of items greater than the page size of the feed are continuously being updated such that they are always at the end of the feed, and this rate of update was faster than the rate of a syncing consumer's polling, the client could never ever catch up to some of these items as they would always be a page away. Thus they would never be able to be aware of these items they never catch up to

It might be worth adding a comment on this limitation to make implementers aware