Entity Framework Core 2.0 add-migration not generating anything

Question

I\'m new to EF and am trying to create a simple test solution using VS 2017, .NET Core 2.0 and EF 2.0 but I can\'t get add-migration to create the migrations folder

Answer 1

I had issues when I attempt to get it to work as well as far as I am concerned EF Core 2.0 is not fully ready for prime time as the main dotnet core commands don't work out of the box. In addition to what you did I had to run a few more things to get it to work in the project file itself. I followed these two threads: https://github.com/aspnet/Scaffolding/issues/645 and Joe Healy's answer here: No executable found matching command "dotnet-ef"

In essence it would do nothing or give a very basic error. It ended up being that the hook up of the Microsoft.EntityFrameworkCore.Tools.DotNet were not working correctly and needed to be set in the 'ItemGroup' in my .NET Core 2 project like so:

 <ItemGroup>
    <DotNetCliToolReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Tools" Version="2.0.1" />
    <DotNetCliToolReference Include="Microsoft.EntityFrameworkCore.Tools.DotNet" Version="2.0.1" />
  </ItemGroup>

I also believe you need to use a slightly different code for making the migrations work utilizing dotnet that calls out commands for 'dotnet core'. Followed by 'ef'. So I just did this on my test solution:

dotnet ef migrations add test

and it worked. You must, must, be in the same folder level as your project when doing the commands for migrations or database updates. If you are still having trouble feel free to take a look at a project I created on GitHub:

https://github.com/djangojazz/EFCoreTest/tree/master/EFCoreCodeFirstScaffolding

Answer 2

@JulieLerman provided the answer when I asked in her pluralsight course discussion. There is apparently an issue with attempting this with the .NET Core class libraries. The successful workaround is to put the following in the csproj file of the DBContext project:

<PropertyGroup>
  <GenerateRuntimeConfigurationFiles>true</GenerateRuntimeConf‌igurationFiles> 
</PropertyGroup>

She wrote a blog about it: http://thedatafarm.com/data-access/the-secret-to-running-ef-core-2-0-migrations-from-a-net-core-or-net-standard-class-library/

Additionally, be sure to set the project with the DBContext in it as the startup project