How to create SIGN UP and LOG IN with Jquery and CouchDb?

How to set up couchDb to perform SignUp and LogIn? Creating special database just for that, or giving evry document username and password. The goal is to retrieve custom document ba开发者_如何学编程sed on user/password. So if one has successful LogIn, couch loads his own document with data only for him! Is there a way to do validation on CouchDb based on user input in client-side, any ideas,examples?

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These are very important questions, and coincidentally, somebody asked the question yesterday of how to log in to a couchapp with private data.

For signup, I recommend the excellent book from O'Reilly: CouchDB: The Definitive Guide which is free online. It has a chapter on users and security.