How do StackExchange sites associate user accounts and OpenID logins?
account-management, asp.net-mvc, openid, openid-provider, user-accounts
Solution
The StackExchange sites use the DotNetOpenAuth library (previously known as DotNetOpenId library).
You basically need a `User` table and a `User_OpenID` table with a one-to-many relationship. Scot Hanselman has a good basic article or try a more in depth overview
Problem
I love StackExhchange / StackOverflow's approach to integrating OpenID. As I understand it, the process goes something like this: - If a user signs up with an OpenID provider (i.e. Google), StackOverflow (or similar site) creates an account for the user and associates the OpenID with that account. - An existing user can associate multiple OpenID accounts with his/her StackExchange account. I would love to emulate this behavior because I haven't seen it nearly as user-friendly on other sites. I know StackExchange is built on ASP.NET MVC, but am not sure whether it uses the standard ASP.NET credentialing model and then adds the OpenID provider in a separate DB table or what. So, my questions are: - How does StackExchange create these accounts? Do they Create a user in the standard ASP.NET MVC provider and then associate the ID, or is there a separate process? - how does StackExchange allow additional OpenID provider accounts to be associated with an existing account? Thanks in advance for any help you can give!