Search code examples
c#asp.net-coreasp.net-mvc-scaffolding

System.InvalidOperationException: Scheme already exists: Identity.Application: After Identity Scaffolding

I had an existing ApplicationUser, and I wanted to modify the UI page of Login. So this is why I decided to perform the scaffold operation.

ApplicationUser.cs 

public class ApplicationUser : IdentityUser
{
    public List<Student> Students { get; set; }
}

But when I use the last CLI command this :

dotnet aspnet-codegenerator identity --files="Account.Login;"

I can't be able to run my web application, this is what it shows on the web :

enter image description here

And then, this is the error which occurs in the log :

Unhandled Exception: System.InvalidOperationException: Scheme already exists: Identity.Application at Microsoft.AspNetCore.Authentication.AuthenticationOptions.AddScheme(String name, Action1 configureBuilder) at Microsoft.AspNetCore.Authentication.AuthenticationBuilder.<>c__DisplayClass4_02.b__0(AuthenticationOptions o) at Microsoft.Extensions.Options.ConfigureNamedOptions1.Configure(String name, TOptions options) at Microsoft.Extensions.Options.OptionsFactory1.Create(String name)
at Microsoft.Extensions.Options.OptionsManager1.<>c__DisplayClass5_0.<Get>b__0() at System.Lazy1.ViaFactory(LazyThreadSafetyMode mode) at System.Lazy1.ExecutionAndPublication(LazyHelper executionAndPublication, Boolean useDefaultConstructor) at System.Lazy1.CreateValue() at Microsoft.Extensions.Options.OptionsCache1.GetOrAdd(String name, Func1 createOptions) at Microsoft.Extensions.Options.OptionsManager1.Get(String name) at Microsoft.Extensions.Options.OptionsManager1.get_Value() at Microsoft.AspNetCore.Authentication.AuthenticationSchemeProvider..ctor(IOptions1 options, IDictionary2 schemes) at Microsoft.AspNetCore.Authentication.AuthenticationSchemeProvider..ctor(IOptions1 options) --- End of stack trace from previous location where exception was thrown --- at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitConstructor(ConstructorCallSite constructorCallSite, ServiceProviderEngineScope scope) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor2.VisitCallSite(IServiceCallSite callSite, TArgument argument) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitScoped(ScopedCallSite scopedCallSite, ServiceProviderEngineScope scope) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitSingleton(SingletonCallSite singletonCallSite, ServiceProviderEngineScope scope) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor`2.VisitCallSite(IServiceCallSite callSite, TArgument argument) at Microsoft.Extensions.DependencyInjection.ServiceLookup.DynamicServiceProviderEngine.<>c__DisplayClass1_0.b__0(ServiceProviderEngineScope scope) at Microsoft.Extensions.DependencyInjection.ServiceLookup.ServiceProviderEngine.GetService(Type serviceType, ServiceProviderEngineScope serviceProviderEngineScope)
at Microsoft.Extensions.DependencyInjection.ServiceLookup.ServiceProviderEngine.GetService(Type serviceType) at Microsoft.Extensions.DependencyInjection.ServiceProvider.GetService(Type serviceType) at Microsoft.Extensions.Internal.ActivatorUtilities.ConstructorMatcher.CreateInstance(IServiceProvider provider) at Microsoft.Extensions.Internal.ActivatorUtilities.CreateInstance(IServiceProvider provider, Type instanceType, Object[] parameters) at Microsoft.AspNetCore.Builder.UseMiddlewareExtensions.<>c__DisplayClass4_0.b__0(RequestDelegate next) at Microsoft.AspNetCore.Builder.Internal.ApplicationBuilder.Build() at Microsoft.AspNetCore.Hosting.Internal.WebHost.BuildApplication() at Microsoft.AspNetCore.Hosting.Internal.WebHost.StartAsync(CancellationToken cancellationToken) at Microsoft.AspNetCore.Hosting.WebHostExtensions.RunAsync(IWebHost host, CancellationToken token, String shutdownMessage) at Microsoft.AspNetCore.Hosting.WebHostExtensions.RunAsync(IWebHost host, CancellationToken token) at Microsoft.AspNetCore.Hosting.WebHostExtensions.Run(IWebHost host)
at ICFERApp.Program.Main(String[] args) in /Users/idrislutaaya/RiderProjects/ICFERApp/ICFERApp/Program.cs:line 17

I had a look on this question but it didn't help me.

Actually what surprises me, there's a DBClass which creates it's self in this directory ~/Areas/Identity/Data, below :

enter image description here

public class ICFERAppIdentityDbContext : IdentityDbContext<IdentityUser>
{
    public ICFERAppIdentityDbContext(DbContextOptions<ICFERAppIdentityDbContext> options)
        : base(options)
    {
    }

    protected override void OnModelCreating(ModelBuilder builder)
    {
        base.OnModelCreating(builder);
        // Customize the ASP.NET Identity model and override the defaults if needed.
        // For example, you can rename the ASP.NET Identity table names and more.
        // Add your customizations after calling base.OnModelCreating(builder);
    }
}

Yet I was having an existing one here :

public class ApplicationDbContext : IdentityDbContext
    {
        public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
            : base(options)
        {
        }

        public DbSet<Student> Students { get; set; }

        protected override void OnModelCreating(ModelBuilder builder)
        {
            base.OnModelCreating(builder);

            builder.Entity<ApplicationUser>()
                .HasMany(s => s.Students)
                .WithOne(u => u.User);


            builder.Entity<Student>()
                .HasOne(e => e.Education)
                .WithOne(s => s.Student);


            builder.Entity<Student>()
                .HasOne(g => g.Guardian)
                .WithOne(s => s.Student);

            builder.Entity<Student>()
                .HasOne(p => p.Parents)
                .WithOne(s => s.Student);

            builder.Entity<Student>()
                .HasOne(s => s.Siblings)
                .WithOne(s => s.Student);

            builder.Entity<Siblings>()
                .Property(p => p.Id)
                .ValueGeneratedOnAdd();

            builder.Entity<Siblings>()
                .HasKey(x => new { x.Id, x.StudentId});

            builder.Entity<Education>()
                .Property(p => p.Id)
                .ValueGeneratedOnAdd();

            builder.Entity<Education>()
                .HasKey(x => new { x.Id, x.StudentId});


            builder.Entity<Guardian>()
                .Property(p => p.Id)
                .ValueGeneratedOnAdd();

            builder.Entity<Guardian>()
                .HasKey(x => new { x.Id, x.StudentId});
            builder.Entity<Parents>()
                .Property(p => p.Id)
                .ValueGeneratedOnAdd();

            builder.Entity<Parents>()
                .HasKey(x => new { x.Id, x.StudentId});


        }
    }

Then, in my Startup.cs file, I followed what the Microsoft doc says :

public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            services.Configure<CookiePolicyOptions>(options =>
            {
                // This lambda determines whether user consent for non-essential cookies is needed for a given request.
                options.CheckConsentNeeded = context => true;
                options.MinimumSameSitePolicy = SameSiteMode.None;
            });

            services.AddIdentity<ApplicationUser, IdentityRole>()
                .AddDefaultUI(UIFramework.Bootstrap4)
                .AddEntityFrameworkStores<ApplicationDbContext>()
                .AddDefaultTokenProviders();

            services.AddDbContext<ApplicationDbContext>(options =>
                options.UseMySql(
                    Configuration.GetConnectionString("DefaultConnection")));


            services.AddTransient<IStudentRepository, StudentRepository>();
            services.AddMvc().AddNToastNotifyToastr();


            services.AddJsReport(new LocalReporting()
                .UseBinary(RuntimeInformation.IsOSPlatform(OSPlatform.Windows)
                    ? JsReportBinary.GetBinary()
                    : jsreport.Binary.OSX.JsReportBinary.GetBinary())
                .AsUtility()
                .Create());

            services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2);


            services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1)
                .AddRazorPagesOptions(options =>
                {
                    options.AllowAreas = true;
                    options.Conventions.AuthorizeAreaFolder("Identity", "/Account/Manage");
                    options.Conventions.AuthorizeAreaPage("Identity", "/Account/Logout");
                });

            services.ConfigureApplicationCookie(options =>
            {
                options.LoginPath = $"/Identity/Account/Login";
                options.LogoutPath = $"/Identity/Account/Logout";
                options.AccessDeniedPath = $"/Identity/Account/AccessDenied";
            });
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
                app.UseDatabaseErrorPage();
            }
            else
            {
                app.UseExceptionHandler("/Home/Error");
                // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
                app.UseHsts();
            }

            app.UseHttpsRedirection();
            app.UseStaticFiles();
            app.UseCookiePolicy();
            app.UseNToastNotify();

            app.UseAuthentication();

            app.UseMvc(routes =>
            {
                routes.MapRoute(
                    name: "default",
                    template: "{controller=Student}/{action=Index}/{id?}");
            });
        }
    }

With all the information above, what really went wrong with my implementation?

Solution

  • Check the IdentityHostingStartup.cs and comment out below line if it exits :

    services.AddDefaultIdentity<IdentityUser>()
    .AddEntityFrameworkStores<ICFERAppIdentityDbContext>();

    In short only one identity configuration is needed . Here is a related discussion .