[development] Super Ninja Question: Auto-creating user and logging in (worth +15 magic points)

[Rob Barreca]

Oh harro,

So an anonymous user hits http://example.com/start-building and we want 
them to be a full-fledged logged in user at the end of the page with no 
redirect to make the session stick. Yes that's right ladies and 
gentlemen, no drupal_goto()!

The issue is, the session doesn't really stick until the next page hit, 
requiring a drupal_goto(). I've been doing some dumping of $_COOKIE to 
watchdog() and noticed that they have a different sess ID on that first 
hit. Then after doing a drupal_goto() they have another sess ID that 
ends up sticking throughout their session.

*My question:* How would I give this anonymous user his/her legit 
session all in this same page hit so any AJAX calls they make from this 
same page (remember, no redirect!) will pass the good cookie, not this 
anonymous cookie (mmm, chocolate).

Also, this triggered something in my brain about Drupal giving anonymous 
user's first hit a different cookie for some reason or another, but I 
forget exactly why. Is that related to my issue? If not, would someone 
mind explaining that anyways or pointing me in the right direction?

Thanks,

RobRoy