How to maintain session information across authentication - session

Question

I using ServiceStack authentication with a custom session object. I've got everything set up with different authentication providers and everything is working fine.
Now a want to store some information in the session before the user is authenticated (Think shopping cart). But we loose that information when the user logs in later. Looking at the code in the documentation this makes sense:
Plugins.Add(new AuthFeature(() => new AuthUserSession(),
new IAuthProvider[] {
new BasicAuthProvider(), //Sign-in with Basic Auth
new CredentialsAuthProvider(), //HTML Form post of UserName/Password credentials
}));
The authentication removes the existing session whenever a user logs in. This makes sense when the old login is a valid user, you want to make sure it's fully logged out. However when the current session isn't authenticated there doesn't seem to be much reason to do so.
I've been looking at a custom session factory, but that doesn't help me because as () => new AuthUserSession() shows, there isn't any context to use when creating the new session. Without a way to get the old session there I've got no way to copy any information.
I can work around it by overriding AuthProvider.Authenticate() and grab the required information before calling base. But that means doing so in every authentication provider we use and the ones we might use in the future. That doesn't really feel like the correct solution.
Is there a cleaner way to carry information across the authentication? Preferably something which works regardless of the AuthProvider used.

Answer 1

Whilst the Typed Sessions are re-created after authenticating, the Permanent and Temporary Session Ids themselves remain the same which lets you use ServiceStack's dynamic SessionBag to store information about a user which you can set in your Services with:
public class UnAuthInfo
{
public string CustomInfo { get; set; }
}
public class MyServices : Service
{
public object Any(Request request)
{
var unAuthInfo = SessionBag.Get<UnAuthInfo>(typeof(UnAuthInfo).Name)
?? new UnAuthInfo();
unAuthInfo.CustomInfo = request.CustomInfo;
SessionBag.Set(typeof(UnAuthInfo).Name, unAuthInfo);
}
}
You can then access the dynamic Session Bag in your Custom AuthUserSession Session Events with:
public class CustomUserSession : AuthUserSession
{
[DataMember]
public string CustomInfo { get; set; }
public override void OnAuthenticated(IServiceBase service, IAuthSession session,
IAuthTokens tokens, Dictionary<string, string> authInfo)
{
var sessionBag = new SessionFactory(service.GetCacheClient())
.GetOrCreateSession();
var unAuthInfo = sessionBag.Get<UnAuthInfo>(typeof(UnAuthInfo).Name);
if (unAuthInfo != null)
this.CustomInfo = unAuthInfo.CustomInfo;
}
}
New Session API's in v4.0.32+
Accessing the Session bag will be a little nicer in next v4.0.32+ of ServiceStack with the new GetSessionBag() and convenience ISession Get/Set extension methods which will let you rewrite the above like:
public object Any(Request request)
{
var unAuthInfo = SessionBag.Get<UnAuthInfo>() ?? new UnAuthInfo();
unAuthInfo.CustomInfo = request.CustomInfo;
SessionBag.Set(unAuthInfo);
}
//...
public override void OnAuthenticated(IServiceBase service, IAuthSession session,
IAuthTokens tokens, Dictionary<string, string> authInfo)
{
var unAuthInfo = service.GetSessionBag().Get<UnAuthInfo>();
if (unAuthInfo != null)
this.CustomInfo = unAuthInfo.CustomInfo;
}