How to add LinkedIn to SignInManager.GetExternalAuthenticationSchemes()

Question

How do I make a custom authentication provider like LinkedIn appear in SignInManager.GetExternalAuthenticationSchemes() from where Login.cshtml picks up by default

Background Details:

I am trying to understand asp.net core identity framework. In that quest, I created a standard .net core project

I tried out the supported Google authentication alongside reading the documentation and it all worked fine for me.

I was able to make LinkedIn authentication work for me, but couldn't understand how to make certain pieces work. To add support for LinkedIn authentication, I made the following changes

Added the below lines In Startup.Configure method

app.UseOAuthAuthentication(new OAuthOptions() {
    AuthenticationScheme = "LinkedIn",
    ClientId = Configuration["Authentication:LinkedIn:ClientID"],
    ClientSecret = Configuration["Authentication:LinkedIn:ClientSecret"],
    CallbackPath = new PathString("/signin-linkedin"),
    AuthorizationEndpoint = "https://www.linkedin.com/oauth/v2/authorization",
    TokenEndpoint = "https://www.linkedin.com/oauth/v2/accessToken",
    UserInformationEndpoint = "https://api.linkedin.com/v1/people/~:(id,formatted-name,email-address,picture-url)",
    Scope = { "r_basicprofile", "r_emailaddress" },
});

Added the required ClientId and ClientSecret to the configuration

Added the following line to the Login.cshtml

<button type="submit" class="btn btn-default" name="provider" value="LinkedIn" title="Log in using your LinkedIn account">LinkedIn</button>

All this works fine. Now my question is:
For supported authentication providers, as soon as I call, say, app.UseGoogleAuthentication in Startup.Configure, my call to SignInManager.GetExternalAuthenticationSchemes() in Login.cshtml lists Google as a provider. What do I need to do, so the call to SignInManager.GetExternalAuthenticationSchemes() will also list LinkedIn as a provider

Answer 1

What do I need to do, so the call to SignInManager.GetExternalAuthenticationSchemes() will also list LinkedIn as a provider

This method only lists the authentication middleware that have been assigned a "display name".

To include Linked in the providers list, set OAuthOptions.DisplayName:

app.UseOAuthAuthentication(new OAuthOptions
{
    DisplayName = "LinkedIn"
    // ...
});