Save last query & timestamp by default

Steps to reproduce

1. dispatch a find in one page of your app.
2. Navigate to another that effectively needs the same data.

Expected behavior

We should have a way to tell how old the cache is and what query populated it. That would allow us to say, not run the query again if it was ran less than a minute ago.

Actual behavior

The cache has no origin information, no information about whether the connection dropped since it was populated and no information about the query that populated it. Therefore, we have no guarantees about the data and are thus forced to implement our optimization or fire the potentially non-trivial query again.

Working with feathers-vuex is currently quite wordy… we should look for ways to cut down lines for the typical app.

Proposed Solution

Lets add a property to the vuex state with

last: {
  createdAt: 14245678921
  query: 'find'
  params: '{}'
}

[FossPrime]

fun real world edge case:

Google play music will only get the playlist list once and pull from cache every time you go to the playlist list page. It will reactively add to the list, but if your laptop is asleep, you’ll end up with missing playlists even though you’ve “browsed” back and forth between pages inside Google Play Music.

AllGet would solve this, but it would be expensive for Google. AllGet([id, maxAge]) would fix the problem without hitting the server every time.

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Off topic, I would really love built in eager updates support that doesn’t require a local proxy copy to support vuex strict mode. Something like patch([id, params, vuexParams]) where I can say {eager: true, rollback: false}.

[marshallswain]

I also like the idea of a maxAge-based cache. As a baby step towards this, I’ve added a createdAt timestamp to the pagination data in feathers-vuex@1.6.2.