Understanding the Rails Authenticity Token

Question

I am running into some issues regarding the Authenticity Token in Rails, as I have many times now.

But I really don\'t want to just solve this problem and go on. I w

Answer 1

Beware the Authenticity Token mechanism can result in race conditions if you have multiple, concurrent requests from the same client. In this situation your server can generate multiple authenticity tokens when there should only be one, and the client receiving the earlier token in a form will fail on it's next request because the session cookie token has been overwritten. There is a write up on this problem and a not entirely trivial solution here: http://www.paulbutcher.com/2007/05/race-conditions-in-rails-sessions-and-how-to-fix-them/