Asp.Net: no suitable constructor for authentication Middleware

Question

I am currently trying to write AuthenticationMiddleware. See this answer . The application works without errors, but when I execute dnx web, I get the following error:

Unable to find a suitable constructor for type 'Namespace.BasicAuthenticationMiddleware'. Make sure that the type is specific and that all parameters are accepted by the constructor.

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

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]

I am sure that the constructor signature I use is wrong, but I can’t find the appropriate documentation for this, as it seems that there are dozens of obsolete ones.

This is the AuthenticationMiddleware property:

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();
    }
}

BasicAuthOptions:

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

BasicAuthenticationExtensions

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

Startup.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

Your extension is UseBasicAuthenticationtrying to inject an instance ConfigureOptionsthat your middleware does not accept as a parameter.

Just execute the options instance as is:

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