今天我们再来了解一个很重要的接口IAuthenticationService的实现类AuthenticationService：
public class AuthenticationService : IAuthenticationService{ ???????public AuthenticationService(IAuthenticationSchemeProvider schemes, IAuthenticationHandlerProvider handlers, IClaimsTransformation transform) ???????{ ???????????Schemes = schemes; ???????????Handlers = handlers; ???????????Transform = transform; ???????} ???????public IAuthenticationSchemeProvider Schemes { get; } ???????public IAuthenticationHandlerProvider Handlers { get; } ???????public IClaimsTransformation Transform { get; } ???????public virtual async Task<AuthenticateResult> AuthenticateAsync(HttpContext context, string scheme) ???????{ ???????????if (scheme == null) ???????????{ ???????????????var defaultScheme = await Schemes.GetDefaultAuthenticateSchemeAsync(); ???????????????scheme = defaultScheme?.Name; ???????????????if (scheme == null) ???????????????{ ???????????????????throw new InvalidOperationException($"No authenticationScheme was specified, and there was no DefaultAuthenticateScheme found."); ???????????????} ???????????} ???????????var handler = await Handlers.GetHandlerAsync(context, scheme); ???????????if (handler == null) ???????????{ ???????????????throw await CreateMissingHandlerException(scheme); ???????????} ???????????var result = await handler.AuthenticateAsync(); ???????????if (result != null && result.Succeeded) ???????????{ ???????????????var transformed = await Transform.TransformAsync(result.Principal); ???????????????return AuthenticateResult.Success(new AuthenticationTicket(transformed, result.Properties, result.Ticket.AuthenticationScheme)); ???????????} ???????????return result; ???????} ???????/// <summary> ???????/// Challenge the specified authentication scheme. ???????/// </summary> ???????/// <param name="context">The <see cref="HttpContext"/>.</param> ???????/// <param name="scheme">The name of the authentication scheme.</param> ???????/// <param name="properties">The <see cref="AuthenticationProperties"/>.</param> ???????/// <returns>A task.</returns> ???????public virtual async Task ChallengeAsync(HttpContext context, string scheme, AuthenticationProperties properties) ???????{ ???????????if (scheme == null) ???????????{ ???????????????var defaultChallengeScheme = await Schemes.GetDefaultChallengeSchemeAsync(); ???????????????scheme = defaultChallengeScheme?.Name; ???????????????if (scheme == null) ???????????????{ ???????????????????throw new InvalidOperationException($"No authenticationScheme was specified, and there was no DefaultChallengeScheme found."); ???????????????} ???????????} ???????????var handler = await Handlers.GetHandlerAsync(context, scheme); ???????????if (handler == null) ???????????{ ???????????????throw await CreateMissingHandlerException(scheme); ???????????} ???????????await handler.ChallengeAsync(properties); ???????} ???????/// <summary> ???????/// Forbid the specified authentication scheme. ???????/// </summary> ???????public virtual async Task ForbidAsync(HttpContext context, string scheme, AuthenticationProperties properties) ???????{ ???????????if (scheme == null) ???????????{ ???????????????var defaultForbidScheme = await Schemes.GetDefaultForbidSchemeAsync(); ???????????????scheme = defaultForbidScheme?.Name; ???????????????... ???????????} ???????????var handler = await Handlers.GetHandlerAsync(context, scheme);
...await handler.ForbidAsync(properties); ???????} ???????/// <summary> ???????/// Sign a principal in for the specified authentication scheme. ???????/// </summary> ???????public virtual async Task SignInAsync(HttpContext context, string scheme, ClaimsPrincipal principal, AuthenticationProperties properties) ???????{
...if (scheme == null) ???????????{ ???????????????var defaultScheme = await Schemes.GetDefaultSignInSchemeAsync(); ???????????????scheme = defaultScheme?.Name; ???????????????... ???????????} ???????????var handler = await Handlers.GetHandlerAsync(context, scheme); ???????????...var signInHandler = handler as IAuthenticationSignInHandler; ???????????...await signInHandler.SignInAsync(principal, properties); ???????} ???????/// <summary> ???????/// Sign out the specified authentication scheme. ???????/// </summary> ???????public virtual async Task SignOutAsync(HttpContext context, string scheme, AuthenticationProperties properties) ???????{ ???????????if (scheme == null) ???????????{ ???????????????var defaultScheme = await Schemes.GetDefaultSignOutSchemeAsync(); ???????????????scheme = defaultScheme?.Name; ???????????????if (scheme == null) ???????????????{ ???????????????????throw new InvalidOperationException($"No authenticationScheme was specified, and there was no DefaultSignOutScheme found."); ???????????????} ???????????} ???????????var handler = await Handlers.GetHandlerAsync(context, scheme); ???????????if (handler == null) ???????????{ ???????????????throw await CreateMissingSignOutHandlerException(scheme); ???????????} ???????????var signOutHandler = handler as IAuthenticationSignOutHandler; ???????????if (signOutHandler == null) ???????????{ ???????????????throw await CreateMismatchedSignOutHandlerException(scheme, handler); ???????????} ???????????await signOutHandler.SignOutAsync(properties); ???????}
}该类通过构造方法，将我们两篇中讲到了IAuthenticationSchemeProvider和IAuthenticationHandlerProvider注入了进来，第三个参数不是很重要就飘过了。拉下来我们看看它的这几个方法AuthenticateAsync、ChallengeAsync、ForbidAsync、SignInAsync和SignOutAsync等方法，他们的套路几乎都一样的，通过注入进来的两个接口的实例，最终获得到IAuthenticationHandler接口实例的同名方法。
关于IAuthenticationService、IAuthenticationHandlerProvider和IAuthenticationSchemeProvider我们又是什么时候注入到服务容器里去的呢？它是在AuthenticationCoreServiceCollectionExtensions这个静态类中的AddAuthenticationCore扩展方法注入到容器中的：
???public static class AuthenticationCoreServiceCollectionExtensions ???{ ???????public static IServiceCollection AddAuthenticationCore(this IServiceCollection services) ???????{
... ???????????services.TryAddScoped<IAuthenticationService, AuthenticationService>(); ???????????services.TryAddSingleton<IClaimsTransformation, NoopClaimsTransformation>(); // Can be replaced with scoped ones that use DbContext ???????????services.TryAddScoped<IAuthenticationHandlerProvider, AuthenticationHandlerProvider>(); ???????????services.TryAddSingleton<IAuthenticationSchemeProvider, AuthenticationSchemeProvider>(); ???????????return services; ???????} ???????public static IServiceCollection AddAuthenticationCore(this IServiceCollection services, Action<AuthenticationOptions> configureOptions) { ???????????... ???????????services.AddAuthenticationCore(); ???????????services.Configure(configureOptions); ???????????return services; ???????} ???}该扩展方法是在Startup的ConfigureServices方法调用的。这个就不贴代码了。
注入完以后呢？怎么使用呢？为了方便使用，aspnetcore为我们在外面又裹了一层，那就是AuthenticationHttpContextExtensions为HttpContext添加的扩展方法。我们可以在Controller如下调用：
public class HomeController : Controller{ ???????public IActionResult Index() ???????{ ???????????var result = HttpContext.AuthenticateAsync(); ???????????return View(result.Result); ???????}}至此认证相关的核心元素介绍完成，本篇到此结束。
aspnetcore 认证相关类简要说明三
原文地址：https://www.cnblogs.com/koeltp/p/9886651.html