How to Implement Authentication and Authorization in a Blazor WebAssembly App?

Question

I am developing a Blazor WebAssembly application and need to implement user authentication and authorization. I am considering using IdentityServer4 for this purpose. Can anyone provide guidance or recommend best practices for implementing secure authentication and authorization in a Blazor WebAssembly app?

Answer 1

To implement authentication and authorization in a Blazor WebAssembly app, you can use the built-in Authentication and Authorization API provided by ASP.NET Core. Here are the high-level steps:

1. Setup Authentication: Configure authentication services in the Program.cs of your Blazor WebAssembly app. You can use various authentication providers like IdentityServer4, Azure AD, or Firebase Authentication.

      builder.Services.AddApiAuthorization();
   

2. Protect Pages/Components: Use the [Authorize] attribute to protect your Blazor components or pages. Users will need to be authenticated to access these resources.

      @page "/secure"
      @attribute [Authorize]
   

3. Access User Information: Inject the AuthenticationStateProvider service into your component to access user information and determine whether the user is authenticated.

      @inject AuthenticationStateProvider AuthenticationStateProvider
   

4. Login/Logout: Implement login and logout functionalities using the SignOutManager and SignInManager services.
5. Test: Ensure to test your implementation with various scenarios to confirm that the authentication and authorization are working as expected.

Answer 2

First identityserver4 is no longer supported and been replaced by duende, which is generally not a free.

https://duendesoftware.com

if you use the blazor WASM individual accounts template, it uses duende for the oauth server.