c# web api owin authentication

Question

I am very new to WebAPi Authentication even it seems OWIN being popular use. I dont understand why I should use EntityFramework for OWIN authentication as ApplicationDbContext is inhreting from IdentityDbContext and IdentityDbContext is in EntityFramework namespace. Below is procedure which is created automatically when we choose Individual User Accounts within WebApi project template:

public partial class Startup
{
    public static OAuthAuthorizationServerOptions OAuthOptions { get; private set; }

    public static string PublicClientId { get; private set; }

    // For more information on configuring authentication, please visit http://go.microsoft.com/fwlink/?LinkId=301864
    public void ConfigureAuth(IAppBuilder app)
    {
        // Configure the db context and user manager to use a single instance per request
        app.CreatePerOwinContext(ApplicationDbContext.Create);
        app.CreatePerOwinContext<ApplicationUserManager>(ApplicationUserManager.Create);

        // Enable the application to use a cookie to store information for the signed in user
        // and to use a cookie to temporarily store information about a user logging in with a third party login provider
        app.UseCookieAuthentication(new CookieAuthenticationOptions());
        app.UseExternalSignInCookie(DefaultAuthenticationTypes.ExternalCookie);

        // Configure the application for OAuth based flow
        PublicClientId = "self";
        OAuthOptions = new OAuthAuthorizationServerOptions
        {
            TokenEndpointPath = new PathString("/Token"),
            Provider = new ApplicationOAuthProvider(PublicClientId),
            AuthorizeEndpointPath = new PathString("/api/Account/ExternalLogin"),
            AccessTokenExpireTimeSpan = TimeSpan.FromDays(14),
            // In production mode set AllowInsecureHttp = false
            AllowInsecureHttp = true
        };

        // Enable the application to use bearer tokens to authenticate users
        app.UseOAuthBearerTokens(OAuthOptions);

        // Uncomment the following lines to enable logging in with third party login providers
        //app.UseMicrosoftAccountAuthentication(
        //    clientId: "",
        //    clientSecret: "");

        //app.UseTwitterAuthentication(
        //    consumerKey: "",
        //    consumerSecret: "");

        //app.UseFacebookAuthentication(
        //    appId: "",
        //    appSecret: "");

        //app.UseGoogleAuthentication(new GoogleOAuth2AuthenticationOptions()
        //{
        //    ClientId = "",
        //    ClientSecret = ""
        //});
    }
}

Within ConfigureAuth procedure ApplicationDbContext is referenced.

Could you pls help me to write simple Authentication with OWIN and not to use EntityFramework?

Thanks.

Answer 1

you don´t need to use EF, yes, the template uses EF and ASPNET Identity to do the authentication, but you can start using the black template and add it without EF, look the following part of code:

1. Startup.cs

public class Startup
{
    public void Configuration(IAppBuilder app)
    {
        HttpConfiguration config = new HttpConfiguration();
        ConfigureOAuth(app);

        WebApiConfig.Register(config);
        app.UseCors(Microsoft.Owin.Cors.CorsOptions.AllowAll);
        app.UseWebApi(config);
    }

    public void ConfigureOAuth(IAppBuilder app) 
    {
        OAuthAuthorizationServerOptions OAuthServerOptions = new OAuthAuthorizationServerOptions()
        {
            AllowInsecureHttp = true,
            TokenEndpointPath = new PathString("/token"),
            AccessTokenExpireTimeSpan = TimeSpan.FromDays(1),
            Provider = new SimpleAuthorizationServerProvider()
        };

        // Token Generation
        app.UseOAuthAuthorizationServer(OAuthServerOptions);
        app.UseOAuthBearerAuthentication(new OAuthBearerAuthenticationOptions());
    }
}

2. SimpleAuthorizationServerProvider.cs

public class SimpleAuthorizationServerProvider : OAuthAuthorizationServerProvider
{
    public override async Task ValidateClientAuthentication(OAuthValidateClientAuthenticationContext context)
    {
        context.Validated();
    }

    public override async Task GrantResourceOwnerCredentials(OAuthGrantResourceOwnerCredentialsContext context)
    {

        context.OwinContext.Response.Headers.Add("Access-Control-Allow-Origin", new[] { "*" });
        if (context.UserName != "Admin")
        {
            context.SetError("upps!", "Wrong data");
            return;
        }

        var identity = new ClaimsIdentity(context.Options.AuthenticationType);
        identity.AddClaim(new Claim("sub", context.UserName));
        identity.AddClaim(new Claim("role", "user"));

        context.Validated(identity);
    }
}

Also, you can download a simple example here: http://1drv.ms/1mmaqtn

Regards,