auth0 authentication issue: HttpContext.Current is null. This code path is only valid when in the execution context of ASP.NET

Question

I am using auth0 for authentication, roles and permission in my application. I am following below tutorial to implement auth0 in my application,

https://auth0.com/docs/quickstart/webapp/aspnet

It created login screen for me, After giving email-id and password it navigates to LoginHandler.ashx. and it shows below error page.

I am getting token, userid and other information but how to resolve this error in handler?

Answer 1

Here is my solution, If anyone facing same problem,

public class LoginCallback : IHttpHandler, IRequiresSessionState
{
    public void ProcessRequest(HttpContext context)
            {
                AuthenticationApiClient client = new AuthenticationApiClient(
                    new Uri(string.Format("https://{0}", ConfigurationManager.AppSettings["auth0:Domain"])));

                var token = client.ExchangeCodeForAccessTokenAsync(new ExchangeCodeRequest
                {
                    ClientId = ConfigurationManager.AppSettings["auth0:ClientId"],
                    ClientSecret = ConfigurationManager.AppSettings["auth0:ClientSecret"],
                    AuthorizationCode = context.Request.QueryString["code"],
                    RedirectUri = context.Request.Url.ToString()
                });

                var profile = client.GetUserInfoAsync(token.Result.AccessToken);

                var user = new List<KeyValuePair<string, object>>
                {
                    new KeyValuePair<string, object>("name", profile.Result.UserName ?? profile.Result.Email),
                    new KeyValuePair<string, object>("email", profile.Result.Email),
                    new KeyValuePair<string, object>("family_name", profile.Result.LastName),
                    new KeyValuePair<string, object>("given_name", profile.Result.FirstName),
                    new KeyValuePair<string, object>("nickname", profile.Result.NickName),
                    new KeyValuePair<string, object>("picture", profile.Result.Picture),
                    new KeyValuePair<string, object>("user_id", profile.Result.UserId),
                    new KeyValuePair<string, object>("id_token", token.Result.IdToken),
                    new KeyValuePair<string, object>("access_token", token.Result.AccessToken),
                    new KeyValuePair<string, object>("refresh_token", token.Result.RefreshToken),
                    new KeyValuePair<string, object>("connection", profile.Result.Identities.First().Connection),
                    new KeyValuePair<string, object>("provider", profile.Result.Identities.First().Provider)
                };

                // NOTE: Uncomment the following code in order to include claims from associated identities
                profile.Result.Identities.ToList().ForEach(i =>
                {
                    user.Add(new KeyValuePair<string, object>(i.Connection + ".access_token", i.AccessToken));
                    user.Add(new KeyValuePair<string, object>(i.Connection + ".provider", i.Provider));
                    user.Add(new KeyValuePair<string, object>(i.Connection + ".user_id", i.UserId));
                });

                // NOTE: uncomment this if you send roles
                 user.Add(new KeyValuePair<string, object>(ClaimTypes.Role, profile.Result.ProviderAttributes["roles"]));

                // NOTE: this will set a cookie with all the user claims that will be converted 
                //       to a ClaimsPrincipal for each request using the SessionAuthenticationModule HttpModule. 
                //       You can choose your own mechanism to keep the user authenticated (FormsAuthentication, Session, etc.)
                FederatedAuthentication.SessionAuthenticationModule.CreateSessionCookie(user);

                if (context.Request.QueryString["state"] != null && context.Request.QueryString["state"].StartsWith("ru="))
                {
                    var state = HttpUtility.ParseQueryString(context.Request.QueryString["state"]);
                    context.Response.Redirect(state["ru"], true);
                }


                context.Response.Redirect("/");

            }
}

Answer 2

I had similar issue (.NET 4.5), my async handler was working until I added following row to Web.config:

<add key="aspnet:UseTaskFriendlySynchronizationContext" value="false" />

I had to replace all awaits with .Result and implement not async IHttpHandler interface in order to get everything working back. I could not remove setting from config since I needed it for Page.RegisterAsyncTask

Maybe it helps someone