How to check availability and reserve usernames in CouchDB?

This question has already been asked and answered: stackoverflow.com/questions/2769716/sele... Please modify your question if you feel it's different in some way Cheers.

This question has already been asked and answered: stackoverflow.com/questions/2769716/sele... Please modify your question if you feel it's different in some way. Cheers.

Jason. Sam's solution is quite helpful however as you say, it may not be a perfect fit for you. I can think of two other options.

Pretend for a moment you are back in SQL. What is the primary key of a user? It is neither the username nor the email but both columns.

Same for CouchDB. So, to absolutely guarantee uniqueness, the answer is simple: it must be the doc _id. For example, for user "jason" with email "[email protected]", POST this doc: { "_id": "jason:jason@gmail.

Com", "other stuff": "blah blah blah" } That is an atomic, transactional, user creation. It could: Succeed, so now you have your new user document Fail because that id already exists and you (intentionally) forgot the _rev property. Great, that user/email combo is already taken!

Of course, to simply check if the name is available you can GET /db/jason:[email protected]. (You could prefix the id like the _users database does, like users:jason:[email protected]—it's up to you. ) Then you can POST it back later.

There is a chance it will be taken in the mean time but that's normal in all "check first, reserve later" forms which are quite common on the web now. The second idea is more just to think carefully about your situation. You said that two users can have the same username and email.

That sounds odd. Maybe I read wrong. Here are some things to think about: Almost nobody shares an email account with somebody else.

Why not make that the actual login name? It's good enough for Facebook. Then the "username" can just be a user's nickname or handle within the system, just a property in the user document.

Two HTTP requests may not be that bad. I think about it this way: If this is a 3-tier architecture (dedicated webserver, couchdb backend), then two HTTP requests is no big deal If it is a 2-tier or hybrid (where browsers hit couchdb directly), then strongly consider using CouchDB for authentication, described in the CouchDB book. CouchDB can handle logins for you, with a form or AJAX.

It is not perfect for every situation but you get great bang-for-the-buck.

P.S. Do you really own jason@gmail. Com? Lucky bastard!

:p – JasonSmith Jul 7 '10 at 4:22.

I understand Sam's solution is helpful and that is actually what I was using. @jhs Thanks for tip for using email address to login. BTW: Unfortunately [email protected] isn't mine :( Jason.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.