Lazy Registration: How to let a guest user start their workflow and prompt registration when they try to save their work?

I'm wondering what I would do to go about letting a guest use my web application without registering, then if they attempt to save their work they are prompted with a registration. This will be in a rails application by the way. Can I just allow public access to part of the work flow, then when they save check if they're a registered user (by session value, or cookie?). If they aren't a registered user, save all their work into the session and let them fill out a sign开发者_如何学编程 out form. On successful registration automatically log them in and initiate the create on the db?

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You will want to keep track of data in the session. Some people suggest making a module or library to deal with data inside the session. For example, you might have a SessionCart class that deals with cart items in the session.

At the point the person decides to become a user, you can store some data in a cookie if you need to recreate the session.