An error occurred while calling method 'ConfigureServices' on startup class

[mdmoura]

On an ASP.NET Core 1.0.1 project I have the following context:

public class Context : IdentityDbContext<User, Role, Int32, UserClaim, UserRole, UserLogin, RoleClaim, UserToken> { 
  public Context(DbContextOptions options) : base(options) { }
  protected override void OnModelCreating(ModelBuilder builder) {
    base.OnModelCreating(builder);
  }
}

Where the entities are the following:

public class User : IdentityUser<Int32, UserClaim, UserRole, UserLogin> { }
public class Role : IdentityRole<Int32, UserRole, RoleClaim> { }
public class RoleClaim : IdentityRoleClaim<Int32> { }
public class UserClaim : IdentityUserClaim<Int32> { }
public class UserLogin : IdentityUserLogin<Int32> { }
public class UserRole : IdentityUserRole<Int32> { }
public class UserToken : IdentityUserToken<Int32> { }

On Startup I have the following:

  services.AddDbContext<Context>(x => x.UseSqlServer(connectionString, y => y.MigrationsHistoryTable("__Migrations")));

  services
    .AddIdentity<User, Role>()
    .AddEntityFrameworkStores<Context, Int32>()
    .AddDefaultTokenProviders();

When I run "dotnet ef migrations add "FirstMigration" I get the following error:

An error occurred while calling method 'ConfigureServices' on startup class 'WebProject.Startup'. Consider using IDbContextFactory to override the initialization of the DbContext at design-time. Error: GenericArguments[0], 'WebProject.User', on 'Microsoft.AspNetCore.Identity.EntityFrameworkCore.UserStore`4[TUser,TRole,TContext,TKey]' violates the constraint of type 'TUser'.

Am I missing something or is this a bug with the new IdentityDbContext?

[ketrex2]

I believe your issue is related to (and fixed) in this code commit:
1a0cd3c

This updated version has not been released yet. To get around the issue, you may want to copy the code in the corrected version into your own, custom UserStore as a temporary workaround.

[mdmoura]

@ketrex So I need to copy the UserStore file:

https://github.com/aspnet/Identity/blob/1a0cd3c4d15be988abefd889853b0c6d973db9f4/src/Microsoft.AspNetCore.Identity.EntityFrameworkCore/UserStore.cs

But how to register this UserStore in my Startup class?

And will there be a release before 1.1 with this fix?
Version 1.1 is scheduled to Q4 2016 / Q1 2017 so it can take a while.

[ketrex2]

@mdmoura
replace

.AddEntityFrameworkStores<Context, Int32>()

with

services.AddUserStore<YourUserStoreClass<YourContextClassName>>()
services.AddRoleStore<RoleStore<YourRoleClassName, YourContextClassName>>()

.AddEntityFrameworkStores() is just a helper method, if you dig into it, all it does is add the two stores to your service container. You can review it here

[HaoK]

Dupe of #855

[mdmoura]

@ketrex

Not sure what the problem is but I added the new UserStore to my code and named it CustomUserStore:

https://github.com/aspnet/Identity/blob/1a0cd3c4d15be988abefd889853b0c6d973db9f4/src/Microsoft.AspNetCore.Identity.EntityFrameworkCore/UserStore.cs

And on Startup I added the following:

.AddUserStore<IdentityUserStore<User, Role, Context, Int32, UserClaim, UserRole, UserLogin, UserToken, RoleClaim>>()
.AddRoleStore<RoleStore<Role, Context, Int32, UserRole, RoleClaim>>();

This compiles but when I run it I get the following error on Program/Main:

Cannot instantiate implementation type 'CoreProject.CustomUserStore`9
[CoreProject.User,CoreProject.Role,CoreProject.Context,System.Int32,CoreProject.UserClaim,
CoreProject.UserRole,CoreProject.UserLogin,CoreProject.UserToken,CoreProject.RoleClaim]' 
for service type 'Microsoft.AspNetCore.Identity.IUserStore`1[CoreProject.User]'.

Any idea why this happens?

[ketrex2]

@mdmoura, I'm afraid that's not enough for me to go on. Any chance you can throw your project in a github repo so I can take a look?

That error indicates that your container does not contain all the necessary members to instantiate your custom UserStore. But without your code, it's hard to tell what the problem is.

[mdmoura]

@ketrex I just added to a demo project to github:
https://github.com/mdmoura/Core

If you start the project with will get an error on Program/Main.

Am I missing something?

[ketrex2]

@mdmoura I have sent you a PR that should get you up and running.
PR 1

[mdmoura]

@ketrex Sorry for the delay. Thank you, that worked fine.

[mdmoura]

With ASP.NET Core 1.1 I tried to use again:

.AddEntityFrameworkStores<Context, Int32>()
.AddDefaultTokenProviders();  

But I get the errors:

System.ArgumentException: 'GenericArguments[0], 'MvcApp.User', on 'Microsoft.AspNetCore.Identity.EntityFrameworkCore.UserStore`4[TUser,TRole,TContext,TKey]' violates the constraint of type 'TUser'.'

TypeLoadException: GenericArguments[0], 'MvcApp.User', on 'Microsoft.AspNetCore.Identity.EntityFrameworkCore.UserStore`9[TUser,TRole,TContext,TKey,TUserClaim,TUserRole,TUserLogin,TUserToken,TRoleClaim]' violates the constraint of type parameter 'TUser'.

Do we still need to use custom UserStore and RoleStore?