How to implement the following bundle - IdentityServer4 + WebApi + Angular2 + External Auth?

Question

Angular

Hello, I'm trying to do the following:
WEB API separate domain
IdentityServer4 API separate domain
Angular 2 Client separate
Mobile APP domain.
Angular 2 client authorizes with an External service (Twitter)

public void Configure(IApplicationBuilder app, ILoggerFactory loggerFactory)
    {
        loggerFactory.AddConsole(LogLevel.Debug);

        app.UseCors("CorsPolicy");

        app.UseIdentity();
        app.UseIdentityServer();

        //after identity before mvc
        app.UseTwitterAuthentication(new TwitterOptions
        {
            AuthenticationScheme = "Twitter",
            DisplayName = "Twitter",
            SignInScheme = "Identity.External",
            ConsumerKey = "key",
            ConsumerSecret = "secret",
            AutomaticAuthenticate = true,
            AutomaticChallenge = true,
            SaveTokens = true,
        });
        app.UseMvc();
    }

The code below saves my token from twitter to the database:

bool result = false;
        var info = await signInManager.GetExternalLoginInfoAsync();
        if (info != null)
        {
            var tempUser = info.Principal;
            var claims = tempUser.Claims.ToList();

            var userIdClaim = claims?.FirstOrDefault(x => x.Type == ClaimTypes.NameIdentifier);
            var email = claims?.FirstOrDefault(x => x.Type == ClaimTypes.Email);

            if (userIdClaim != null)
            {
               var isRegistered = await IsUserRegistered(info.LoginProvider, info.ProviderKey);
                if (!isRegistered && email != null)
                {
                    var user = new ApplicationUser { UserName = userIdClaim.Value, Email = email.Value };
                    var userCreated = await userManager.CreateAsync(user);
                    isRegistered = userCreated.Succeeded;

                    if (isRegistered)
                    {
                        var addLoginresult = await userManager.AddLoginAsync(user, info);
                        isRegistered = addLoginresult.Succeeded;
                        if (isRegistered)
                        {
                            await signInManager.SignInAsync(user, isPersistent: false);
                        }
                    }
                }

                if (isRegistered)
                {
                    var succeded = await signInManager.ExternalLoginSignInAsync(info.LoginProvider, info.ProviderKey, isPersistent: false);
                    if (succeded.Succeeded)
                    {
                        IdentityResult updateResult = await signInManager.UpdateExternalAuthenticationTokensAsync(info);
                        result = updateResult.Succeeded;
                    }
                }
            }
        }

        if (!result)
        {
            await signInManager.SignOutAsync();
        }

        return Redirect(System.Net.WebUtility.UrlDecode(returnUrl));

At the moment, it is not clear how I can get a valid token from this, which I could return to the client (at the moment the cookie is being returned), with the token later authorized in other apishkas or resources.

Answer 1

For now, I haven't been able to figure it out.
But perhaps the problem is that I receive an external token from twitter,
and I need to somehow get the internal token issued by ID4 and already use it.