Google App Engine 1.4.0

General
1

Hi, everybody,

There were some good news for the GAE users lately - the new 1.4.0 version was released. Some useful stuff was added to the sdk. One of those is
Channel API
. I wonder if it is possible for Vaadin developers to use that one in their apps. Cause push technology with icepush seems not to be applicable in case of GAE. The API looks rather straightforward. However, there’s Javascript part for the client side. I can figure out how to solve some steps of integrating that, e.g. injecting of javascript in the page source is possible with overridng the GAEApplicationServlet methods. But the further work, like setting the handlers for the events and sending events to the others is not quite understandable for me (can it be somehow reached with JSNI or Javascript API or smth else?). I would really appreciate if somebody more experienced (developers, professionals?) would give me a hint if it is at least possible to make Channel API run in the Vaadin App.

Thank You!

2

Yes that would be an excellent feature. I’m currently reading up on the Channels API. Will be following this thread closely. Hope somebody turns up with a nice answer.

There is this project that provides a simple GWT module to interact with the Channel API:


gwt-gae-channel

3

Actually, I saw this one already and managed to make it run more or less with Vaadin. In ideal world, where I am not very constrained with the time, it could turn out to be a good addon I guess.
What i’ve done - was injecting the parts of that sample Google project into a custom widget and everything looks okay. Still some polishing is needed, cause I sometimes get the Exceptions from the channel API in a localhost mode that neither affect the development stage testing stuff nor appear in the logs at App Engine.