ASP.NET Core Web API

builder.Services.AddControllers();

var app = builder.Build();

if (!app.Environment.IsDevelopment())
{
    app.UseHttpsRedirection();
}

app.UseAuthentication();
app.UseAuthorization();

app.MapControllers();

app.Run();

using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;

namespace Auth0Api.Controllers;

[ApiController]
[Route("api/[controller]")]
public class MessagesController : ControllerBase
{
    [HttpGet]
    public IActionResult GetPublic()
    {
        return Ok(new { Message = "This endpoint is public" });
    }

    [Authorize]
    [HttpGet("private")]
    public IActionResult GetPrivate()
    {
        var userId = User.FindFirst("sub")?.Value;
        return Ok(new { Message = "This endpoint is protected", UserId = userId });
    }

    [Authorize(Policy = "read:messages")]
    [HttpGet("messages")]
    public IActionResult GetMessages()
    {
        return Ok(new { Messages = new[] { "Message 1", "Message 2" } });
    }
}

builder.Services.AddAuthorization(options =>
{
    options.AddPolicy("read:messages", policy =>
        policy.RequireClaim("scope", "read:messages"));
    
    options.AddPolicy("write:messages", policy =>
        policy.RequireClaim("scope", "write:messages"));
});

builder.Services.AddAuth0ApiAuthentication(options =>
{
    options.Domain = builder.Configuration["Auth0:Domain"];
    options.JwtBearerOptions = new JwtBearerOptions
    {
        Audience = builder.Configuration["Auth0:Audience"]
    };
}).WithDPoP();  // デフォルト設定で DPoP を有効化

using Microsoft.AspNetCore.Authorization;

namespace Auth0Api.Authorization;

public class HasScopeRequirement : IAuthorizationRequirement
{
    public string Scope { get; }
    public string Issuer { get; }

    public HasScopeRequirement(string scope, string issuer)
    {
        Scope = scope;
        Issuer = issuer;
    }
}

using Microsoft.AspNetCore.Authorization;

namespace Auth0Api.Authorization;

public class HasScopeHandler : AuthorizationHandler<HasScopeRequirement>
{
    protected override Task HandleRequirementAsync(
        AuthorizationHandlerContext context,
        HasScopeRequirement requirement)
    {
        if (!context.User.HasClaim(c => c.Type == "scope" && c.Issuer == requirement.Issuer))
        {
            return Task.CompletedTask;
        }

        var scopes = context.User
            .FindFirst(c => c.Type == "scope" && c.Issuer == requirement.Issuer)?
            .Value.Split(' ');

        if (scopes?.Any(s => s == requirement.Scope) == true)
        {
            context.Succeed(requirement);
        }

        return Task.CompletedTask;
    }
}

using Auth0Api.Authorization;

var builder = WebApplication.CreateBuilder(args);

var domain = $"https://{builder.Configuration["Auth0:Domain"]}";

builder.Services.AddAuth0ApiAuthentication(options =>
{
    options.Domain = builder.Configuration["Auth0:Domain"];
    options.JwtBearerOptions = new JwtBearerOptions
    {
        Audience = builder.Configuration["Auth0:Audience"]
    };
});

builder.Services.AddAuthorization(options =>
{
    options.AddPolicy("read:messages", policy =>
        policy.Requirements.Add(new HasScopeRequirement("read:messages", domain)));
});

builder.Services.AddSingleton<IAuthorizationHandler, HasScopeHandler>();

var app = builder.Build();
// ... 残りの構成

using Microsoft.IdentityModel.Tokens;
using System.Security.Claims;

builder.Services.AddAuth0ApiAuthentication(options =>
{
    options.Domain = builder.Configuration["Auth0:Domain"];
    options.JwtBearerOptions = new JwtBearerOptions
    {
        Audience = builder.Configuration["Auth0:Audience"],
        
        TokenValidationParameters = new TokenValidationParameters
        {
            ValidateIssuerSigningKey = true,
            ValidateIssuer = true,
            ValidateAudience = true,
            ValidateLifetime = true,
            ClockSkew = TimeSpan.FromMinutes(5),
            NameClaimType = ClaimTypes.NameIdentifier,
            RoleClaimType = "https://my-app.com/roles"
        },
        
        Events = new JwtBearerEvents
        {
            OnAuthenticationFailed = context =>
            {
                Console.WriteLine($"Authentication failed: {context.Exception.Message}");
                return Task.CompletedTask;
            },
            
            OnTokenValidated = context =>
            {
                var userId = context.Principal?.FindFirst("sub")?.Value;
                Console.WriteLine($"Token validated for user: {userId}");
                return Task.CompletedTask;
            }
        }
    };
});