TypeLoadException using PostgreSQL with ASP.NET Core Identity

Question

I am attempting to use PostgreSQL as the data store for user authentication in an ASP.NET Core 1.0 Visual Studio 2015 project following installation of VS2015 Update 3 and the Core 1.0 release.

Steps:

1. Create new "ASP.NET Core Web Application (.NET Framework)" project.

2. Add NuGet packages "Npgsql" v3.1.4 and "Npgsql.EntityFrameworkCore.PostgreSQL" v1.0.0-rc2-release1

3. Modify ConfigureServices() in Startup.cs as follows:

    public void ConfigureServices(IServiceCollection services) { // Add framework services. services.AddEntityFrameworkNpgsql() .AddDbContext<ApplicationDbContext>(options => options.UseNpgsql(Configuration.GetConnectionString("DefaultConnection"))); services.AddIdentity<ApplicationUser, IdentityRole>() .AddEntityFrameworkStores<ApplicationDbContext>() .AddDefaultTokenProviders(); services.AddMvc(); // Add application services. services.AddTransient<IEmailSender, AuthMessageSender>(); services.AddTransient<ISmsSender, AuthMessageSender>(); } 

4. Run

5. Exception thrown on call to AddDbContext():

An exception of type 'System.TypeLoadException' occurred in MyApp.exe but was not handled in user code

Additional information: Could not load type 'Microsoft.Extensions.DependencyInjection.Extensions.ServiceCollectionExtensions' from assembly 'Microsoft.Extensions.DependencyInjection.Abstractions, Version=1.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'.

I assume this is a compatibility issue that will soon be addressed in Npgsql.EntityFrameworkCore.PostgreSQL, but wanted to confirm this and determine if a workaround is available.

Answer 1

UPDATE: This has been fixed .

This is a known issue on github, it will be fixed soon.

6/29/2016

FYI 3.1.5 is out, targeting .NET Core RTM. The EFCore provider isn't out yet, that will take another day or two.