caching an xml file in clojure and compojure

[M O N S T E R]

I have a webserver running \[code\]compojure\[/code\]. The webserver reads data from an XML file provided by another server. I don't want to bomb the provider of the file with requests and the XML file doesn't change too often, so I figured I need some kind of caching.I could either store the XML file locally and refresh it every X minutes. The other way would be to reparse the original in the same time interval and store the file in memory? Maybe I can use \[code\]refs\[/code\] or \[code\]atoms\[/code\] for this? This process should probably run in a different thread. How would I configure this?In the future I might have quite a big pool of these XML files that will all need updating.Which would be the best way to do this?