pub fn use_query<Q: QueryCapability>(query: Query<Q>) -> UseQuery<Q>Expand description
Queries are used to get data asynchronously (e.g external resources such as HTTP APIs), which can later be cached or refreshed.
Important concepts:
§Stale time
This is how long will a value that is cached, considered to be recent enough. So in other words, if a value is stale it means that its outdated and therefore it should be refreshed.
By default the stale time is 0ms, so if a value is cached and a new query subscriber
is interested in this value, it will get refreshed automatically.
See Query::stale_time.
§Clean time
This is how long will a value kept cached after there are no more subscribers of that query.
Imagine there is Subscriber 1 of a query, the data is requested and cached.
But after some seconds the Subscriber 1 is unmounted, but the data is not cleared as the default clean time is 5min.
A few seconds later the Subscriber 1 gets mounted again, it requests the data again but this time it is returned directly from the cache.
See Query::clean_time.
§Interval time
This is how often do you want a query to be refreshed in the background automatically. By default it never refreshes automatically.
See Query::interval_time.