An "Activity Viewer" for Ajax

As I participated in the Ajax Summit we put together with Adaptive Path this past week, I dispatched a steady stream of notes and action items to my Backpack. While each would faithfully show up in turn in just a second or less, occasional network hiccups gave me pause (quite literally as I waited for that yellow highlight to put me at ease).

But what if they never made it, these fleeting thoughts and must-do to-dos?

With Javascript chatting asynchronously to the back-end server behind the scenes, there's not much to go on if something doesn't go. No chance to click that Submit button again and give the Web another spin. Imagine if this were so for your IMAP email: if all the filing, flagging, deleting, and responding you took such care to catch up on during that flight simply timed out and disappeared into the ether.

While clearly an early swipe at this issue, Julien Couvreur's "XMLHttpRequest Tracing" for AJAX debugging provides at least a view into the sub-page traffic akin to the Activity Viewer window you can pop open in Mac OS X Mail to watch your mail go by.

Obviously this issue applies not just to Backpack or indeed Ajax methods, but to many a Web 2.0 application (think of a chain of web service API calls, for instance) that doesn't behave according to the traditional "Submit > timeout > Submit > repeat as necessary" pattern end-users have come to expect -- dislike, but expect -- on Web 1.0. What does Web 2.0 notify/retry, or, indeed, transaction/rollback, look like?