In one of my previous posts about Google Wave I mentioned a security issue concerning gadgets. I decided to do a little more research on this subject and to do some experiments on some publicly available gadgets.

The issue

Before I get into detail about the issue, you need to know how Google Wave gadgets work. Gadgets are little pieces of html/javascript code that run inside of a wave. The state of a gadget is shared among every participant of the wave. Developers can access variables in this state by executing wave.getState().get(’name_of_variable’). To save or update variables into the state the following function exists. wave.getState().submitDelta({’name_of_variable’: value})

This is part 3 of my Google Wave developer sandbox review. Part 1 and part 2 were both an introduction to some wave concepts. In this part we’ll be taking a look at the Google Wave Gadget API by writing a simple rating gadget. If you don’t know what gadgets are or what they do, please read my previous post here.

The gadget

The gadget I have written is supposed to be used when you want wave participants to rate something inside your wave (or the wave itself). You simply add the gadget to your wave, set the title and you’re good to go. I also wanted the gadget to have a settings menu that was only visible by the person who added the gadget to the wave.

As the first part of my Google Wave developer sandbox review handled basic usage, this article will be about some more advanced features currently in the Google Wave developer sandbox.

Attachments

Adding attachments to a wave works similar to adding attachments to an email. You click the attachment button, select one or more files, click submit and voila. Your files are uploaded to and displayed inside the wave.

You can attach almost any filetype to a wave. In case you have one or more image files the thumbnails of these files are displayed inside the wave. When you click on a thumbnail the larger image is displayed on a dark background. When there are multiple images added to a wave you can browse them by clicking the image button at the bottom and selecting “view as slideshow”.

Two days after I got my invitation to the Ubuntu One beta and wrote a review about my first impressions I also received an invitation to join the Google Wave developer sandbox. As my Ubuntu One review was pretty popular (had about 1k pageviews the first day – thank you dzone.com users), I decided to write something down about my first Google Wave experiences.

I will divide the review into a few separate pieces. This post will handle the general Google Wave Sandbox stuff, things I noticed when I first used the service. A second post will handle some advanced wave concepts like search, attachments, gadgets and robots. The last two posts will be about writing a gadget and a robot on the platform. I still have no idea about what kind of gadget and robot to write so if you have any suggestions/ideas, please leave a comment at the bottom of this page.