Caching Requests

[athuler]

Currently, many requests made are duplicates (using different subsets of the same response).

It may be worthwhile to investigate caching responses for a certain amount of time by default to avoid duplicate requests and server overload.

[dmv1167]

#25 I implemented caching of route, stop, vehicle, and alert objects, although not of the API requests themselves and not on any sort of timing basis. Caches must be refreshed manually for the time being.