One thing we have to think of is how to use pagination and sorting. A search could go across the whole resource tree hitting different resource providers. For example one use case is getting all vanity paths. Sorting such a search is possible, the resource resolver implementation always picks one result from all providers, compares them, brings them into an order etc. That's definitely doable.
However pagination is a different beast. Of course, for paging the result needs to be sorted. Today, a common practice for doing pagination is key based pagination: with the search result you get a key that is used for the next page. We can easily do this if the search is just hitting a single resource provider. However if the search targets more than one, pagination becomes a problem. For example, if the search has a page size of 20 and two providers might provide resources. Asking each of them for 20 entries, is not very efficient. Asking each provider for ten, hoping that it's evenly split does usually not work either. I guess one could come up with some clever algorithm that solves the problem by potentially doing two (or more ) searches against a provider. But this will be complicated and not really perform well. So I think, we should support sorting across providers, but pagination only across a single provider and throw some exception if a search potentially hits more than one provider. It's a limitation we can document. WDYT? Regards Carsten -- Carsten Ziegeler Adobe Research Switzerland [email protected]
