c# - Asp.Net:没有适合 AuthenticationMiddleware 的构造函数

Question

我目前正在尝试编写一个 AuthenticationMiddleware。参见 this answer .该应用程序构建没有错误，但是当我执行 dnx web 时，出现以下错误:

Unable to locate suitable constructor for type 'Namespace.BasicAuthenticationMiddleware'. Ensure the type is concrete and all parameters are accepted by a constructor.

at Microsoft.Extensions.Internal.ActivatorUtilities.CreateInstance(IServiceProvider provider, Type instanceType, Object[] parameters)

at Microsoft.AspNet.Builder.UseMiddlewareExtensions.<>c__DisplayClass2_0.b__0(RequestDelegate next)

at Microsoft.AspNet.Builder.Internal.ApplicationBuilder.Build()

at Microsoft.AspNet.Hosting.Internal.HostingEngine.BuildApplication()

fail: Microsoft.AspNet.Hosting.Internal.HostingEngine[7]

我确定我使用的构造函数签名在某些方面是错误的，但我找不到合适的文档，因为似乎有许多已弃用的文档。

这是 AuthenticationMiddleware:

public class BasicAuthenticationMiddleware : AuthenticationMiddleware<BasicAuthOptions>
{
    public BasicAuthenticationMiddleware(
        RequestDelegate next, 
        BasicAuthOptions options, 
        ILoggerFactory loggerFactory, 
        IUrlEncoder urlEncoder)
        : base(next, options, loggerFactory, urlEncoder) {}

    protected override AuthenticationHandler<BasicAuthOptions> CreateHandler()
    {
        return new BasicAuthenticationHandler();
    }
}

基本授权选项:

public class BasicAuthOptions : AuthenticationOptions {
    public const string Scheme = "BasicAuth";
    public BasicAuthOptions()
    {
        AuthenticationScheme = Scheme;
        AutomaticAuthenticate = true;
    }
}

基本身份验证扩展

public static class BasicAuthenticationExtensions
{
    public static void UseBasicAuthentication(this IApplicationBuilder builder) {
        builder.UseMiddleware<BasicAuthenticationMiddleware>(new ConfigureOptions<BasicAuthOptions>(o => new BasicAuthOptions()));
    }
}

启动.cs:

public class Startup
{
    public Startup(IHostingEnvironment env)
    {
        // Set up configuration sources.
        var builder = new ConfigurationBuilder()
            .AddJsonFile("appsettings.json")
            .AddEnvironmentVariables();
        Configuration = builder.Build();
    }

    public IConfigurationRoot Configuration { get; set; }

    // This method gets called by the runtime. Use this method to add services to the container.
    public void ConfigureServices(IServiceCollection services)
    {
        // Add framework services.
        services.AddMvc();

        services.AddAuthorization(options => {
            options.AddPolicy(BasicAuthOptions.Scheme, policy => policy.Requirements.Add(new BasicAuthRequirement()));
        });
    }

    // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
    public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
    {
        loggerFactory.AddConsole(Configuration.GetSection("Logging"));
        loggerFactory.AddDebug();

        app.UseIISPlatformHandler();

        app.UseStaticFiles();

        app.UseBasicAuthentication();

        app.UseMvc();
    }

    // Entry point for the application.
    public static void Main(string[] args) => Microsoft.AspNet.Hosting.WebApplication.Run<Startup>(args);
}

Answer 1

您的 UseBasicAuthentication 扩展试图注入(inject)您的中间件不作为参数的 ConfigureOptions 实例。

简单地按原样流动选项实例:

public static class BasicAuthenticationExtensions {
    public static void UseBasicAuthentication(this IApplicationBuilder builder) {
        builder.UseMiddleware<BasicAuthenticationMiddleware>(new BasicAuthOptions());
    }
}