Updating glyphs is still unsupported, and there's no good use case for doing so. When we're using a stale glyph PBF, and the fresh answer contains changed to that glyph, we will continue to use the old glyph.
This is a naïve implementation that essentially merges updated data into existing data. It will *not* remove icons from the stale sprite if they aren't present in the fresh sprite (we aren't tracking the source of a sprite, and the user could have changed it as well). Similarly, it will not update icons that have changed in dimension. This is a rare edge case and probably not worth implementing.
We're now supporting using stale TileJSON and GeoJSON data. When we receive a new answer with an updated TileJSON file, we're replacing the Source's metadata with the new one and trigger updates to make sure we're loading the correct tiles. Similarly, GeoJSON data will be reparsed.
This adds support for using cached styles that are stale. They're treated like changing styles; when the refreshed style changed compared to the one we've already had, we're swapping out the entire style, which might cause a slight flicker.
If you use many different caches, expired weak_ptrs will pile up in the unordered_map, but that is an edge case, and you probably shouldn't do that anyway.
I regenerated assets.zip so that all file paths have an `assets/` prefix, as the Android AssetFileSource implementation asserts, and removed `TEST_DATA` from the paths.
* Move asset:// URL handling to DefaultFileSource.
* AssetFileSource implements FileSource interface and follows familiar implementation patterns.
* Move default implementation to platform/default, zip implementation to platform/android.
* Don't bother with modified / expires / etag -- assets are not cached so it doesn't matter.
* Don't bother with interleaving individual IO calls on the implementation thread. That adds a lot of complexity for very little benefit.
The cache `accessed` field resolution is 1s, so we
need to sleep a little bit more in order to make
sure that the cache entries we are refreshing will have
a different `accessed` time than the other entries.
Added aliases for std::chrono typedefs (eg. 'Seconds' for
std::chrono::seconds). These aliases are used together with templated
helper functions to replace time_t with std::chrono::seconds for most
cases, in particular for 'modified' and 'expires' values in Response.
When we get a request with an explicit expiration time, we're now starting a timer, and will trigger a refresh once the data expires. This gives requesters a chance to update their data.
We're now returning stale responses from cache. Those responses will have the `stale` flag set to true. Currently, all requesters in the core code discard stale responses, and cancel the request immediately after they got a non-stale response.
By not automatically destroying Request objects after the result has been delivered, we are making sure that we can potentially fire the callback multiple times without adverse effects. This means that you have to hold on to the result of fs->request(), can explicitly cancel it if you don't want to be notified of data changes anymore. Not doing so will monitor the request indefinitely and will prevent the app from exiting.
Instead of transforming between return value and callback, pass
the wrapped callback on to the invoked function as the last argument.
This eliminates the need for multiple invokeWithArgument overloads
and permits invoked functions to be asynchronous.
