Unfortunately, part of the whole point of my system is that all I store is the ISBN (and my own recommendation). I get everything else from Amazon daily, which includes the price info, etc. Maybe I have to save all of that in persistent storage and just refresh it every day, but I was hoping to avoid all that.
If you're curious about the site, it's at http://recommended-books.kousenit.com . Its purpose is to be a simple illustration of how to use Java and Groovy on GAE. I'm more concerned, though, that I'm misunderstanding what the cache is for. If there's a separate cache on each instance of the cluster, then it's much less useful for this particular application. Ken On Oct 28, 11:24 am, Nick <[email protected]> wrote: > So this boils down to JCache (google memory) vs Persistent storage > (google disks), right? > > Does this pattern work instead? > > 1. Query Amazon for what you need > 2. Store results using a persistent > storagehttp://code.google.com/appengine/docs/java/datastore/ > > Example:http://code.google.com/appengine/docs/java/datastore/creatinggettinga...) > > PersistenceManager pm = PMF.get().getPersistenceManager(); > > Employee e = new Employee("Alfred", "Smith", new Date()); > > try { > pm.makePersistent(e); > } finally { > pm.close(); > } > > 3. Read from the persistent storage. If this is slow (I have no idea) > you could then use JCache to cache (on each google server instance > hosting an instance of your class) the persistent storage result the > same way you do now > > On Oct 28, 10:37 am, kousen <[email protected]> wrote: > > > > > I'll definitely turn on logging and try to see what's going on. > > > Thanks, > > > Ken > > > On Oct 28, 4:18 am, leszek <[email protected]> wrote: > > > > It looks ok, the only problem I can see that something can happen > > > between storing book in cache and getting book from cache. > > > Scenario like: > > > 1) fetch book from Amazon and store in cache. > > > 2) book expires in Amazon (or any other event happens) > > > 3) next request - get data from cache - you return status of the book > > > at the point 1), not the point 2). > > > > But maybe this problem does not matter very much. > > > > If you want to see if it is working simply use logging and watch the > > > log > > > entries.http://code.google.com/intl/pl/appengine/docs/java/runtime.html > > > > I don't know if there is any method of sending request simultaneously > > > - maybe Amazon API supports some king of "batch requests" - but I'm > > > guessing only.- Hide quoted text - > > > - Show quoted text - --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en -~----------~----~----~----~------~----~------~--~---
