Cache data from a webservice in Ruby on Rails

Question

Hi,

is there a way or even a gem if I want to cache data retrieved from a webservice? The data should expire and been updated for example after one week.

I have a model where I store the ID from an entry of a webservice. Then I get the data and display it to the user. But what if the webservice is unavailable? Or if lots of users uses my site, then I don't want to overload the service (and it's faster with caching, I think).

Hope, anybody got a solution.

thx, tux.