I'm really impressed with the functionality and capability found in the GWT async RPC mechanism which defines
com.google.gwt.user.client.rpc.RemoteService
com.google.gwt.user.server.rpc.RemoveServiceServlet
Due to the extreme limitations in the GAE hosting environment, I'm needing to bridge requests from a GAE server to another non-GAE server.
Is there a way to use the same DTOs and async RPC mechanism I'm using with the browser->server when communicating server->server ?
When you write a GWT/App-Engine App you compile and load the .class files as well as the comiled Javascript to one source. A client comes along downloads your Javascript and GWT does it's magic between the client and server.
Let's assume that now you want to forward some of the RPC calls to another server. You would need to make sure that the Serialization Ids were identical. You now have a problem that will give you fits when you don't keep every thing exactly in sync.
My recommendation to tou would be to use JSON, XML or just text for the calls that you need to forward. It now becomes easy to use the URL Fetch service of GAE.