How to redirect on backend for Angular application using Itfoxtec to access app through Azure Active Directory

Question

I am new to using ITfoxtec for Azure Active Directory SAML logins. I read the StackOverflow entry for Nuget ITfoxtec SAML & Angular (and other similar entries for CORS issues), but I still do not understand how to adapt the GitHub Angular example from https://github.com/ITfoxtec/ITfoxtec.Identity.Saml2 to my needs. When running the ITfoxtec GitHub example, the Login method of the AuthController.cs file is immediately executed when I launch the test Angular application, and brings up the Azure Active Directory login prompt.

For my application, I need to click a "Login using Azure Active Directory" button on the Angular front end to call a backend method that can then redirect to another method to attempt login.

.NetCore C# code:

SSOController.cs file:
// This method is called by an Angular front end button when the user wishes to log in via Azure Active Directory SSO
        [AllowAnonymous]
        [Route("AzureAuth")]
        [HttpGet]
        public IActionResult AzureAuth(string returnUrl = null)
        {
                    var binding = new Saml2RedirectBinding();
                    Saml2Configuration config = GetSamlConfig();

                    binding.SetRelayStateQuery(new Dictionary<string, string> { { relayStateReturnUrl, returnUrl ?? Url.Content("https://localhost:44397/api/sso/AssertionConsumerService") } });
                    //return binding.Bind(new Saml2AuthnRequest(config)).ToActionResult();  
// This gives a CORS error, so we have do ensure that we do the redirection at the backend
// so we try redirecting with "RedirectToAction"
                     return RedirectToAction("https://localhost:44397/api/sso/AssertionConsumerService"); 

        }

My AssertionConsumerService() method (located in Dev at "https://localhost:44397/api/sso/AssertionConsumerService"), which I need to be redirected to:

        [Route("AssertionConsumerService")]
        [HttpPost]
        public async Task<IActionResult> AssertionConsumerService(HttpRequestMessage request)
        {
// After user enters AAD SSO information, redirect should point to here.
// This API endpoint is hit if I test from Azure Enterprise Application SSO testing with the redirect API set to this method.
// I do not understand how to do backend redirects from AzureAuth() method to this method, and ensure that the HTTP request data is correct.
}

score 1 · Answer 1 · answered Apr 15 '22 at 13:10

Just a follow up to my own question. For logging in directly from the Angular front end, I am having success with using "@azure/msal-angular". Once the end user clicks the "Log in with Azure Active Directory" button and is authenticated back to the frontend, I forward the authentication details to the backend for authorization checks.

I am still using ITfoxtec at the backend to process what can be directly sent from the "Azure Enterprise Applications > Set up single sign on > Test single sign-on with ..." for testing purposes. With the Azure "App registrations > Authentication > Platform Configuration" set to "Single-Page Application", I am making good progress in development and testing.

score 0 · Answer 2 · answered Apr 19 '22 at 09:37

Sounds like you got a solution. You can load the Angular application before login if it is hosted a place in the ASP.NET application that do not require the user to be authenticated. Then you can start the login process your selv and validate if the user is authenticated.

How to redirect on backend for Angular application using Itfoxtec to access app through Azure Active Directory

2 Answers2

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