使用ninject的Asp.net成员资格提供程序-调用Initialize方法

Question

I am trying to implement a custom membership provider in an asp.net mvc 4 web application using ninject for dependency injection. Here is the code I have until now.

public interface IAccountRepository
{
    void Initialize(string name, NameValueCollection config);
    string ApplicationName { get; set; }
    bool ChangePassword(string username, string oldPassword, string newPassword);
    bool ChangePasswordQuestionAndAnswer(string username, string password, string newPasswordQuestion,
        string newPasswordAnswer);
    MembershipUser CreateUser(string username, string password, string email, string passwordQuestion,
        string passwordAnswer, bool isApproved, object providerUserKey, out MembershipCreateStatus status);
    bool DeleteUser(string username, bool deleteAllRelatedData);
    bool EnablePasswordReset { get; }
    bool EnablePasswordRetrieval { get; }
    MembershipUserCollection FindUsersByEmail(string emailToMatch, int pageIndex, int pageSize,
        out int totalRecords);
    /* I have deleted here all other methods and properties of membership for brevity */
}

.

public class AccountRepository : IAccountRepository
{
    private string applicationName;
    private bool enablePasswordReset;
    private bool enablePasswordRetrieval;
    private int maxInvalidPasswordAttempts;
    private int minRequiredNonAlphanumericCharacters;
    private int passwordAttemptWindow;
    private MembershipPasswordFormat passwordFormat;
    private string passwordStrengthRegularExpression;
    private bool requiresQuestionAndAnswer;
    private bool requiresUniqueEmail;
    private int minRequiredPasswordLength;

    public void Initialize(string name, NameValueCollection config)
    {
        applicationName = GetConfigValue(config["applicationName"], HostingEnvironment.ApplicationVirtualPath);
        maxInvalidPasswordAttempts = Convert.ToInt32(GetConfigValue(config["maxInvalidPasswordAttempts"], "5"));
        passwordAttemptWindow = Convert.ToInt32(GetConfigValue(config["passwordAttemptWindow"], "10"));
        minRequiredNonAlphanumericCharacters = Convert.ToInt32(GetConfigValue(config["minRequiredNonAlphanumericCharacters"], "1"));
        minRequiredPasswordLength = Convert.ToInt32(GetConfigValue(config["minRequiredPasswordLength"], "6"));
        enablePasswordReset = Convert.ToBoolean(GetConfigValue(config["enablePasswordReset"], "true"));
        passwordStrengthRegularExpression = Convert.ToString(GetConfigValue(config["passwordStrengthRegularExpression"], ""));
    }

    public string ApplicationName
    {
        get { return applicationName; }
        set { applicationName = value; }
    }

    public bool ChangePassword(string username, string oldPassword, string newPassword)
    {
        throw new NotImplementedException();
    }

    public bool ChangePasswordQuestionAndAnswer(string username, string password, string newPasswordQuestion,
        string newPasswordAnswer)
    {
        throw new NotImplementedException();
    }

    public MembershipUser CreateUser(string username, string password, string email, string passwordQuestion,
        string passwordAnswer, bool isApproved, object providerUserKey, out MembershipCreateStatus status)
    {
        throw new NotImplementedException();
    }

    public bool DeleteUser(string username, bool deleteAllRelatedData)
    {
        using (var database = new KinematDbContext())
        {
            // Query to get the user with the specified username
            User user = database.Users.SingleOrDefault(u => u.Username == username);

            if (user != null)
            {
                if (deleteAllRelatedData)
                {
                    database.Users.Remove(user);
                }
                else
                {
                    user.IsDeleted = true;
                }

                database.SaveChanges();
                return true;
            }

            return false;
        }
    }

    public bool EnablePasswordReset
    {
        get { return enablePasswordReset; }
    }

    public bool EnablePasswordRetrieval
    {
        get { return enablePasswordRetrieval; }
    }

    public MembershipUserCollection FindUsersByEmail(string emailToMatch, int pageIndex, int pageSize,
        out int totalRecords)
    {
        throw new NotImplementedException();
    }

    public MembershipUserCollection FindUsersByName(string usernameToMatch, int pageIndex, int pageSize,
        out int totalRecords)
    {
        throw new NotImplementedException();
    }

    /* I have deleted here all other methods and properties of membership for brevity */
}

.

public class AccountMembershipProvider : MembershipProvider
{
    [Inject]
    public IAccountRepository AccountRepository { get; set; }

    public override void Initialize(string name, NameValueCollection config)
    {
        base.Initialize(name, config);
        AccountRepository.Initialize(name, config); 
        /* Here comes the error: Object reference not set to an instance of an object. */
    }

    public override string ApplicationName
    {
        get { return AccountRepository.ApplicationName; }
        set { AccountRepository.ApplicationName = value; }
    }

    public override bool ChangePassword(string username, string oldPassword, string newPassword)
    {
        return AccountRepository.ChangePassword(username, oldPassword, newPassword);
    }
}

and this is my ninject controller factory(I also have set the controller factory in Application_Start())

public class NinjectControllerFactory : DefaultControllerFactory
{
    private IKernel ninjectKernel;

    public NinjectControllerFactory()
    {
        ninjectKernel = new StandardKernel();
        AddBindings();
    }

    protected override IController GetControllerInstance(RequestContext requestContext, Type controllerType)
    {
        return controllerType == null ? null : (IController)ninjectKernel.Get(controllerType);
    }

    private void AddBindings()
    {
        ninjectKernel.Bind<IAccountRepository>().To<AccountRepository>();
        ninjectKernel.Bind<IRoleRepository>().To<RoleRepository>();
        ninjectKernel.Inject(Membership.Provider);
        ninjectKernel.Inject(Roles.Provider);
    }
}

as I mention in a comment in the AccountMembershipProvider class when the AccountRepository.Initialize(name, config); is called I receive the following error: Object reference not set to an instance of an object. After debugging the application and read articles about how ninject works I cannot figure out what the problem is about. Please, can you give any explanation? Thank you.

Answer 1

Try to do the initialization for registering instances in Global.asax.

public class MvcApplication : System.Web.HttpApplication { protected void Application_Start() { AreaRegistration.RegisterAllAreas();

        WebApiConfig.Register(GlobalConfiguration.Configuration);
        FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
        RouteConfig.RegisterRoutes(RouteTable.Routes);
        // TODO register your binding here
        ...
    }
}

Answer 2

I've run into a similar problem using a Custom Membership Provider. If you want to call the initialize method in the AccountRepository you could do the following:

Configure your DI with ninject in App_Start using the following (available via nuget):

public static class NinjectWebCommon 
{
    private static readonly Bootstrapper bootstrapper = new Bootstrapper();

    /// <summary>
    /// Starts the application
    /// </summary>
    public static void Start() 
    {
        DynamicModuleUtility.RegisterModule(typeof(OnePerRequestHttpModule));
        DynamicModuleUtility.RegisterModule(typeof(NinjectHttpModule));
        bootstrapper.Initialize(() => CreateKernel());
    }

    /// <summary>
    /// Stops the application.
    /// </summary>
    public static void Stop()
    {
        bootstrapper.ShutDown();
    }

    /// <summary>
    /// Creates the kernel that will manage your application.
    /// </summary>
    /// <returns>The created kernel.</returns>
    private static IKernel CreateKernel()
    {
        var kernel = new StandardKernel();
        kernel.Bind<Func<IKernel>>().ToMethod(ctx => () => new Bootstrapper().Kernel);
        kernel.Bind<IHttpModule>().To<HttpApplicationInitializationHttpModule>();

        RegisterServices(kernel);
        DependencyResolver.SetResolver(new NinjectServiceLocator(kernel));
        return kernel;
    }

    /// <summary>
    /// Load your modules or register your services here!
    /// </summary>
    /// <param name="kernel">The kernel.</param>
    private static void RegisterServices(IKernel kernel)
    {
        //add your bindings here
        kernel.Bind<IAccountRepository>().To<AccountRepository>();

        kernel.Bind<MembershipProvider>().To<AccountMembershipProvider>().InRequestScope();
        kernel.Bind<RoleProvider>().To<AccountRoleProvider>().InRequestScope(); //In case you have a custom Role Provider. 

    }

}

Then in your custom provider:

public class AccountMembershipProvider : MembershipProvider
{
    private readonly IAccountRepository _repository;

    public AccountMembershipProvider()
    {
        _repository = ServiceLocator.Current.GetInstance<IAccountRepository>();
        _repository.Initialize();
    }

    public override bool ValidateUser(string username, string password)
    {
        return _repository.IsValidLogin(username, password);
    }

    ...//Other methods
}

Hope this helps,

Answer 3

Not the answer you're looking for, but I tried to do this myself a while ago and while I did manage to find a way to make it work, I found the solution to be too complex and brittle for production use.

I simply gave up on the idea of using Injection with my custom provider, because of the way Membership creates the provider. It's just not worth the headaches in my opinion.

I also think using Injection breaks the whole concept of the Membership provider, since the idea is that providers are supposed to be pluggable, and you can replace one with another without making any changes to your code. That's simply not possible to do if you have to have configuration code in your app to configure the database context..

Ok, you might argue that you won't be changing the provider.. in which case, Why bother with the provider at all then? Why not just implement a custom IIdentity and IPrincipal implementations.

Answer 4

How about adding the following line into your AddBindings() method

kernel.Bind<AccountMembershipProvider>().ToMethod(ctx => Membership.Provider);

I used ninject and custom membership provider with mvc3 Not sure if it helps you but you can compare yours with mine.

[assembly: WebActivator.PreApplicationStartMethod(typeof(VBooks.Web.App_Start.NinjectWebCommon), "Start")]
[assembly: WebActivator.ApplicationShutdownMethodAttribute(typeof(VBooks.Web.App_Start.NinjectWebCommon), "Stop")]

namespace VBooks.Web.App_Start
{
    using System;
    using System.Web;

    using Microsoft.Web.Infrastructure.DynamicModuleHelper;

    using Ninject;
    using Ninject.Web.Common;

    public class ProviderInitializationHttpModule : IHttpModule
    {
        public ProviderInitializationHttpModule(MembershipProvider membershipProvider) { }
        public void Init(HttpApplication context) { }


        void IHttpModule.Dispose()
        {

        }
    } 

    public static class NinjectWebCommon 
    {
        private static readonly Bootstrapper bootstrapper = new Bootstrapper();

        /// <summary>
        /// Starts the application
        /// </summary>
        public static void Start() 
        {
            DynamicModuleUtility.RegisterModule(typeof(OnePerRequestHttpModule));
            DynamicModuleUtility.RegisterModule(typeof(NinjectHttpModule));
            bootstrapper.Initialize(CreateKernel);
        }

        /// <summary>
        /// Stops the application.
        /// </summary>
        public static void Stop()
        {
            bootstrapper.ShutDown();
        }

        /// <summary>
        /// Creates the kernel that will manage your application.
        /// </summary>
        /// <returns>The created kernel.</returns>
        private static IKernel CreateKernel()
        {
            var kernel = new StandardKernel();
            kernel.Bind<Func<IKernel>>().ToMethod(ctx => () => new Bootstrapper().Kernel);
            kernel.Bind<IHttpModule>().To<HttpApplicationInitializationHttpModule>();

            //
            RegisterServices(kernel);

            return kernel;
        }

        /// <summary>
        /// Load your modules or register your services here!
        /// </summary>
        /// <param name="kernel">The kernel.</param>
        private static void RegisterServices(IKernel kernel)
        {
            kernel.Bind<IRegisterService>().To<RegisterService>();
            kernel.Bind<IEmailService>().To<EmailService>();
            kernel.Bind<IAccountService>().To<AccountService>();
            kernel.Bind<ICoverService>().To<CoverService>();
            kernel.Bind<IAdminLogService>().To<AdminLogService>();
            kernel.Bind<MembershipProvider>().ToMethod(ctx => Membership.Provider);
            kernel.Bind<IHttpModule>().To<ProviderInitializationHttpModule>();

            // Add data and infrastructure modules     
            var modules = new List<INinjectModule>
            {
                new RepositoryModule()
            };

            kernel.Load(modules);

        }  

    }
}

Answer 5

Instead of implementing DefaultControllerFactory you can implement IDependencyResolver :

public class NinjectDependencyResolver : IDependencyResolver
{
    readonly IKernel _kernel;

    public NinjectDependencyResolver()
    {
        _kernel = new StandardKernel();
        AddBindings();
    }

    public object GetService(Type serviceType)
    {
        return _kernel.TryGet(serviceType);
    }

    public IEnumerable<object> GetServices(Type serviceType)
    {
        return _kernel.GetAll(serviceType);
    }

    void AddBindings()
    {
        // Remember to add bindings here.
        _kernel.Bind<IAccountRepository>().To<EFAccountRepository>();
    }
}

Then in global.asax.cs instead of setting ControllerFactory you can set DependencyResolver :

public class MvcApplication : System.Web.HttpApplication
{
    protected void Application_Start()
    {
        AreaRegistration.RegisterAllAreas();

        WebApiConfig.Register(GlobalConfiguration.Configuration);
        FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
        RouteConfig.RegisterRoutes(RouteTable.Routes);

        DependencyResolver.SetResolver(new NinjectDependencyResolver()); // Here.
    }
}

Then in your implementation of MembershipProvider ask current DependencyResolver(Ninject) to create you an instance of, in this case, IAccountRepository :

public class CustomMembershipProvider : MembershipProvider
{
    private readonly IAccountRepository _repository;

    public OpenTibiaMembershipProvider()
    {
        _repository = (IAccountRepository)DependencyResolver.Current.GetService(typeof(IAccountRepository));
    }

    // Rest of implementation.
}

Hope this helps.