Support Callback Data in javascript OpenSRF requests

Code at working/user/dyrcona/lp939535 on evergreen-ils.org/working/OpenSRF.git.

This feels like it was too easy.

I think previously this kind of thing was handled by tacking ad-hoc fields onto the request object. E.g. req._mystuff = foo; I like the idea of formalizing it, though. One comment on the code... I could be wrong, I haven't tested this, but wouldn't it be enough to capture the callbackdata in the OpenSRF.Request constructor (like you have), but without passing it around to the other layers? Inside the caller's oncomplete() handler, they can acces the callback data like => oncomplete : function(req) { var cbd = req.callbackdata; ... }

Bill,

I'm so used to doing callbacks in C and similar languages that I used the approach required there.

After coding the above, I did realize that I probably could have just made the variables visible at certain levels and then access it from the call backs. I do, however, prefer the formality of the C-style callback data.

If you think the code should be changed a bit, then that's fine. I'll just need to alter my code that uses it.

Jason, Bill - have you guys come to a conclusion on this? I'd like to know whether I should roll this branch into 2.1.0 RC2.

Sorry for holding things up, Dan. I have no objections to Jason's code.