The entity type 'Microsoft.AspNet.Identity.EntityFramework.IdentityUserLogin<string>' requires a key to be defined

Question

I have a ASP.NET5 MVC application using EF7. It works all fine so far and i'm able to add migrations and persist data in the database. Now after adding Identity to my data layer project I get this error when trying to add a new migration:

The entity type 'Microsoft.AspNet.Identity.EntityFramework.IdentityUserLogin' requires a key to be defined

My context is derived from IdentityDbContext:

public class ASSWebApiContext : IdentityDbContext<AppUser>

the AppUser class:

using Microsoft.AspNet.Identity.EntityFramework;
using System;

namespace ASS.DomainDataModel.Models
{
    public class AppUser : IdentityUser
    {
        public string AppUserId { get; set; }
        public DateTime FirstFlight { get; set; }
    }
}

project.json

{
  "version": "1.0.0-*",
  "description": "ASS.DomainDataModel Class Library",
  "authors": [ "xxxx" ],
  "tags": [ "" ],
  "projectUrl": "",
  "licenseUrl": "",

  "frameworks": {
    "dnx451": {
      "dependencies": {
      }
    },
    "dnxcore50": {
      "dependencies": {
      }
    }
  },

  "dependencies": {
    "ASS.DomainClasses": "1.0.0-*",
    "Microsoft.Extensions.PlatformAbstractions": "1.0.0-rc1-final",
    "Microsoft.Extensions.Configuration.EnvironmentVariables": "1.0.0-rc1-final",
    "Microsoft.Extensions.Configuration.FileExtensions": "1.0.0-rc1-final",
    "Microsoft.Extensions.Configuration.Json": "1.0.0-rc1-final",
    "EntityFramework.Core": "7.0.0-rc1-final",
    "EntityFramework.Commands": "7.0.0-rc1-final",
    "EntityFramework.Relational": "7.0.0-rc1-final",
    "System.Linq.Expressions": "4.0.11-beta-23516",
    "EntityFramework.MicrosoftSqlServer": "7.0.0-rc1-final",
    "Microsoft.AspNet.Identity.EntityFramework": "3.0.0-rc1-final"
  },

    "commands": {
    "ef": "EntityFramework.Commands"
  }
}

All I have done here is to load the relevant new package: "Microsoft.AspNet.Identity.EntityFramework": "3.0.0-rc1-final", added the AppUser class - nothing else. I had a similar project using beta-8 using the exact same pattern where it worked without problems. Are there any relevant changes between beta-8 and rc-1?

thanks!

Below is part of the ASSWebApiContext. There's a modelBuilder.Entity for most of the entities that have a DbSet. So the file goes on for quite a while...

using Microsoft.Data.Entity;
using ASS.DomainClasses.Entities;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.PlatformAbstractions;
using System.Linq;
using ASS.DomainClasses.Interfaces;
using System;
using Microsoft.AspNet.Identity.EntityFramework;

namespace ASS.DomainDataModel.Models
{
    public class ASSWebApiContext : IdentityDbContext<AppUser>
    {
        public IConfigurationBuilder Config { get; set; }
        public IConfigurationRoot _Configuration { get; private set; }

        public ASSWebApiContext(IApplicationEnvironment appEnv)
        {
            Database.EnsureCreated();

            Config = new ConfigurationBuilder()
                .SetBasePath(appEnv.ApplicationBasePath)
                .AddJsonFile("config.json");

            _Configuration = Config.Build();

        }

        public DbSet<Address> Addresses { get; set; }
        public DbSet<AddressType> AddressTypes { get; set; }
        public DbSet<Aircraft> Aircrafts { get; set; }
        public DbSet<AircraftModel> AircraftModels { get; set; }
        public DbSet<AircraftOwner> AircraftOwners { get; set; }
        public DbSet<AircraftOwnerType> AircraftOwnerTypes { get; set; }
        public DbSet<Country> Countries { get; set; }
        public DbSet<GPEncodingType> GPEncodingTypes { get; set; }
        public DbSet<LocationPoint> LocationPoints { get; set; }
        public DbSet<Manufacturer> Manufacturer { get; set; }
        public DbSet<Pilot> Pilots { get; set; }
        public DbSet<ServiceProvider> ServiceProviders { get; set; }
        public DbSet<State> States { get; set; }
        public DbSet<Trip> Trips { get; set; }
        public DbSet<Stop> Stops { get; set; }
        public DbSet<Track> Tracks { get; set; }


        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {


            modelBuilder.Entity<AddressType>(
                e =>
                {
                    e.Property(n => n.AddressTypeId).IsRequired().UseSqlServerIdentityColumn();
                    e.Property(n => n.Name).IsRequired().HasMaxLength(15);
                    e.Ignore(n => n.IsDirty);
                });

            modelBuilder.Entity<Address>(
                e =>
                {
                    e.Property(n => n.AddressId).IsRequired().UseSqlServerIdentityColumn();
                    e.Property(n => n.AddressTypeId).IsRequired();
                    e.Property(i => i.CountryId).HasMaxLength(2);
                    e.Property(i => i.AddrLine1).HasMaxLength(256);
                    e.Property(i => i.AddrLine2).HasMaxLength(256);
                    e.Property(i => i.AddrLine3).HasMaxLength(256);
                    e.Property(i => i.Postcode).HasMaxLength(50);
                    e.Ignore(n => n.IsDirty);
                });
...

Answer 1

Basically the keys of Identity tables are mapped in OnModelCreating method of IdentityDbContext and if this method is not called, you will end up getting the error that you got. This method is not called if you derive from IdentityDbContext and provide your own definition of OnModelCreating as you did in your code. With this setup you have to explicitly call the OnModelCreating method of IdentityDbContext using base.OnModelCreating statement. This answer also discusses the option I posted here