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by WhyNotHugo 6 days ago
There's guaranteed persistence, but there's no guarantee that the host will be up anytime soon. E.g.: I might leave a final reply with all the details on an issue before going on vacation (or maybe I don't work the next day but my colleagues abroad do!). I see that it's properly posted and close the laptop.

The reply with be delayed by days or weeks, but the UI indicated that it had been properly saved.
1 comments
pier25 6 days ago
> There's guaranteed persistence

There's not. Browsers can delete "persistent" storage at any time.

https://developer.mozilla.org/en-US/docs/Web/API/Storage_API...

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12_throw_away 6 days ago
It depends. From the link:

> If, for any reason, developers need persistent storage [...] they can do so by using the navigator.storage.persist() method of the Storage API.

This makes a request for guaranteed permanent storage ... which can be approved (or denied) by the user or by browser defaults.

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ifwinterco 6 days ago
Edge case but playing devil’s advocate: a user can also uninstall the native app at any time, and might still expect their last change before they closed the app to be reflected in the web version.

You can never truly trust anything about a client because by definition you don’t control it

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killingtime74 6 days ago
But the os can't uninstall the native app at any time unprompted right
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aforwardslash 6 days ago
Corner case: actually, it can. Also, thats how auto-updating works ; depending on local state as a source of truth using browser apis is a terrible idea IMO.

The whole concept of "assume it is committed while we sync in the background" is, in the most cases, a terrible architectural decision, unless it is coupled with explicit feedback (eg. A small visual indicator indicating if the background queue is empty or syncing). Also, it breaks temporality: last-update-wins no longer holds, because update time and sync time are decoupled. And you also create a new problem, which is local cache coherence.

It may be a good fit for some systems (though I cannot think of a single one), but in general is just a horrible solution.

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ifwinterco 6 days ago
No, it’s definitely a lot less likely and probably an edge case you can ignore in practice
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WhyNotHugo 3 days ago
Quite true. This doesn't negate my point thought: it actually makes the argument stronger.
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