Spatial index from/over resources

Apparently (looking at the code) if I load a GeoJson resource I can have a preview (the geoview) but the resource itself is NOT indexed, only a package containing the spatial extra bbox field (geojson snippet) is indexed.

Would be interesting to have ALSO an index for each of the attached resource of type geojson (and gml, wkb, etc), is there something available?

is there a way (out of the box) to calculate the extent of all the resources to obtain the envelope (bbox) of the containing package?