Cookies Authentication in Blazor 8 with Individual Accounts: Solving the API Controller Conundrum

Are you tired of banging your head against the wall trying to get cookies authentication to work with individual accounts in Blazor 8? Do you have an API controller that refuses to recognize your authenticated user? Fear not, dear developer, for we’re about to embark on a journey to resolve this pesky issue once and for all!

The Problem: A Brief Overview

In Blazor 8, when you choose the “Individual Accounts” option during project creation, you’re presented with a half-baked authentication system that seems to work fine for Razor components but fails miserably when it comes to API controllers. This is because the default implementation of individual accounts uses the Microsoft.AspNetCore.Authentication.Cookies middleware to handle authentication, but it’s not configured to work with API controllers out of the box.

The Culprit: Missing Middleware Configuration

The root cause of the issue lies in the fact that the Startup.cs file lacks the necessary middleware configuration to enable cookies authentication for API controllers. By default, the services.AddAuthentication() method only adds the authentication services for Razor components, not for API controllers.

public void ConfigureServices(IServiceCollection services)
{
    services.AddAuthentication(options =>
    {
        options.DefaultScheme = "Cookies";
    })
    .AddCookie(options =>
    {
        options.LoginPath = "/Identity/Account/Login";
        options.LogoutPath = "/Identity/Account/Logout";
    });
}

The Solution: Configuring Middleware for API Controllers

To get cookies authentication working with individual accounts for API controllers, we need to add the Microsoft.AspNetCore.Authentication.JwtBearer middleware to our Startup.cs file. This will enable JWT bearer token authentication for our API controllers.

public void ConfigureServices(IServiceCollection services)
{
    services.AddAuthentication(options =>
    {
        options.DefaultScheme = "Cookies";
        options.DefaultChallengeScheme = "oidc";
    })
    .AddCookie(options =>
    {
        options.LoginPath = "/Identity/Account/Login";
        options.LogoutPath = "/Identity/Account/Logout";
    })
    .AddJwtBearer(options =>
    {
        options.Audience = "https://localhost:5001";
        options.Authority = "https://localhost:5001";
        options.TokenValidationParameters = new TokenValidationParameters
        {
            ValidateIssuer = true,
            ValidateAudience = true,
            ValidateLifetime = true,
            ValidateIssuerSigningKey = true
        };
    });
}

ConfigureServices: A Breakdown

• services.AddAuthentication(): Adds the authentication services to the DI container.
• options.DefaultScheme = "Cookies": Sets the default authentication scheme to “Cookies”.
• options.DefaultChallengeScheme = "oidc": Sets the default challenge scheme to “oidc” (OpenID Connect).
• AddCookie(): Adds the cookies middleware to the pipeline.
• AddJwtBearer(): Adds the JWT bearer token middleware to the pipeline.
• options.Audience and options.Authority: Set the audience and authority for the JWT bearer token validation.
• TokenValidationParameters: Configures the token validation parameters.

Implementation: Putting it all Together

Now that we’ve configured the middleware, let’s create a simple API controller to demonstrate how cookies authentication works with individual accounts.

[ApiController]
[Route("api/[controller]")]
public class VALUESController : ControllerBase
{
    [Authorize]
    [HttpGet]
    public IActionResult GetValues()
    {
        return Ok(new[] { "Value 1", "Value 2" });
    }
}

In this example, we’ve added the [Authorize] attribute to the GetValues() method to enforce authentication. When we make a GET request to the /api/VALUES endpoint, the API controller will challenge the user to authenticate using the cookies middleware.

Testing the Implementation

To test our implementation, let’s create a simple Razor page to authenticate the user and then make a request to our API controller.

@page "/"
@using Microsoft.AspNetCore.Authentication



Login

@code {
    async Task Login()
    {
        await Microsoft.AspNetCore.Authentication.AuthenticationHttpContextExtensions
            .ChallengeAsync((HttpContext)@this.HttpContext, "Cookies");
    }
}

In this example, we’ve created a simple Razor page with a “Login” button. When the button is clicked, the Login() method is called, which challenges the user to authenticate using the cookies middleware.

using System.Net.Http;
using System.Text;
using System.Threading.Tasks;

@code {
    async Task RequestApi()
    {
        var httpClient = new HttpClient();
        httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", await HttpContext.GetTokenAsync("access_token"));

        var response = await httpClient.GetAsync("https://localhost:5001/api/VALUES");
        response.EnsureSuccessStatusCode();

        var responseBody = await response.Content.ReadAsStringAsync();
        Console.WriteLine(responseBody);
    }
}

Once the user is authenticated, we can make a GET request to our API controller using the HttpClient class. We set the Authorization header to include the access token obtained from the HttpContext.

Conclusion: Cookies Authentication in Blazor 8 with Individual Accounts

In this article, we’ve demonstrated how to configure cookies authentication with individual accounts in Blazor 8 to work with API controllers. By adding the Microsoft.AspNetCore.Authentication.JwtBearer middleware and configuring the token validation parameters, we can enable JWT bearer token authentication for our API controllers. With this implementation, we can now authenticate users and authorize access to our API controllers using cookies authentication.

Remember to replace the placeholder values in the code snippets with your own implementation-specific values. Happy coding!

Keyword	Description
Blazor 8	A web framework for building web applications using C# and Razor.
Individual Accounts	An authentication option in Blazor 8 that provides a simple way to manage user accounts.
Cookies Authentication	A type of authentication that uses cookies to store and transmit authentication information.
JWT Bearer Token	A type of token used for authentication and authorization in web applications.
API Controller	A type of controller in ASP.NET Core that handles API requests and returns data in a specific format.

This article is optimized for the keyword “Cookies authentication in Blazor 8 having Individual Accounts as authentication not working for API controller”. If you have any further questions or need clarification on any of the topics covered, feel free to ask!

Here are 5 questions and answers about “Cookies authentication in Blazor 8 having Individual Accounts as authentication not working for API controller”:

Frequently Asked Questions

Having trouble with cookies authentication in Blazor 8 using Individual Accounts? You’re not alone! Check out these FAQs to get your authentication working smoothly with your API controllers.