Hi,

I know another thread that I created (previous forum thread) more than a year ago partially asked this issue of how Liferay could possibly work on cloud services like Amazon EC2 and Google App Engine. It's pretty obvious that Liferay would work on Amazon EC2. However, would Liferay run on Google App Engine, especially when and if Google App Engine gets the full upgrade to Google App Engine for Business. In particular, would Liferay run when GAE for Business gets its hosted SQL service up and running? I think using Google's BigTable (without SQL) was the biggest impediment of Liferay on GAE in the past.

Is there someone from Liferay who can update or speculate on whether Liferay would run on GAE for Business (using the hosted SQL service)?

From initial reading at http://code.google.com/appengine/docs/java/runtime.html it sounds like Liferay *could* work since GAE has all the necessary components, but it would take a lot of re-arranging of Liferay bits to make it fit into the GAE environment. Also, the 'sandbox' sounds like it will be problematic for a default Liferay install, since Liferay assumes it has unfettered access to the filesystem (e.g. for document library default filesystem-based hook). I don't see how you could just extract a Liferay .zip bundle onto a GAE environment and start it up, but if you could take the various parts of it (the web app, the config files, etc) and surgically place them in the right spots on GAE it should work.

Hi James,

Do you know if anybody put a coding effort into this? I have a customer that is potentially interested but i need to gauge the pitfalls before i commit,

cheers,
Aad

I don't know of anyone. After reading this overview from wikipedia, it seems like it *might* work (it is based on servlet 2.5 and Jetty as a container, which LR works with), but there are some things that stick out that scare me:

• 'Existing web applications that require a relational database will not run on App Engine without modification." - this one scares me the most!
• programs can only access a white-listed subset of JRE classes
• can only use the OS's filesystem in readonly mode (they have a virtual filesystem that you could use, but you'd have to carefully configure LR to not require local filesystem access, and potentially need to write a doclib hook so that it can use google's virtual filesystem)
• "Datastore cannot use inequality filters on more than one entity property per query"

So, those seem like pretty big hurdles to me.

As of writing this response, the Wikipedia article appears to be outdated. In the meantime Google has released Google Cloud SQL, which will overcome the two cited points above.

Here is a list of white listed JRE classes. With this it should be fairly easy to determine if/ where Liferay uses other classes too.

I currently have the impression that it comes down to the file system access. Depending on how Liferay implements the file system access (outside the war deployment container), it might be possible to build a virtual file system (i.e. based on fuse), which utilizes Google Blobstore.

Possibly someone could answer my related question with this post?