OpenIdConnect configurations with OKTA - asp.net-mvc

Question

I have a web applicaiton that uses OpenIdConnectAuthenntication. There are Maps to login and logout pages. Sample shown below for login.
app.Map("/login.aspx", map =>
{
map.Run(ctx =>
{
if (ctx.Authentication.User == null || !ctx.Authentication.User.Identity.IsAuthenticated)
{
// trigger authentication
ctx.Response.StatusCode = 401;
}
else
{
ctx.Response.Redirect("/");
}
return Task.FromResult(0);
});
});
I am trying to find a way to completely exit out of the openidconnect option and redirect user to an entirely new web application when it gets to statuscode = 401 line.
Here the aim is that I have two applications A and B. Both make use of OKTA authentication. For some reason I need the users who are coming to application A directly be redirected to B and have them login there. Once authenticated from B they will be routed to A. I need B to be the entry gate for application A.

Answer 1

There is an AuthenticationFailed event (called Notifications) in the OpenID Owin implementation
In example
app.UseOpenIdConnectAuthentication(new OpenIdConnectAuthenticationOptions
{
// config...
ClientId = //...,
ClientSecret = // ...,
// etc
// events
Notifications = new OpenIdConnectAuthenticationNotifications
{
// AuthenticationFailed
AuthenticationFailed = context =>
{
context.HandleResponse();
// Handle redirect
//context.Response.Write(context.Exception.Message);
//_logger.Log(context.Exception.Message);
return Task.FromResult(0);
},
// ...
}
}
More complete example can be found here https://github.com/EricHerlitz/Identityserver4-Episerver-Demo/blob/master/IdEpi/IdEpi.WebEpiserver/Business/Owin/Startup.cs