How to retrieve Facebook Public_profile data in MVC 6

Hi,

I am trying to make a project in ASP.NET 5 MVC 6 and using Facebook External Login. Everything is working fine in the default template.

I want to capture Gender information which is available in "public_profile" permission.

In MVC 5 I was able to do it through Provider OnAuthentication method as shown in the below code which I am not able to find its equivalent in MVC 6:

 var facebookAuthOptions = new FacebookAuthenticationOptions();
        facebookAuthOptions.AppId = "..."; //Enter your AppId
        facebookAuthOptions.AppSecret = "..."; //Enter your AppSecret
 facebookAuthOptions.Provider = new FacebookAuthenticationProvider()
    {
        OnAuthenticated = async context =>
            {
                context.Identity.AddClaim(new System.Security.Claims.Claim("FacebookAccessToken", context.AccessToken));
                foreach (var claim in context.User)
                {
                    var claimType = string.Format("urn:facebook:{0}", claim.Key);
                    string claimValue = claim.Value.ToString();
                    if (!context.Identity.HasClaim(claimType, claimValue))
                        context.Identity.AddClaim(new System.Security.Claims.Claim(claimType, claimValue, "XmlSchemaString", "Facebook"));
                }
            }
    };

I tried to find OnAuthentication method in Identity3 but could not find it.

Can anyone please help me with the same as I am trying to retrieve the following information: Gender, FirstName, LastName which is available through public_profile scope.