Microsoft.VisualStudio.Web.CodeGeneration.Design package not being found by the dotnet aspnet-codegenerator tool

I just created an MVC app with dotnet new mvc --name test-project (netcoreapp3.1), without any kind of database access and Identity, which I would like to add by hand for customisation purposes. Then I added some packages in order to use the dotnet aspnet-codegenerator tool. My .csproj looks like this:

<Project Sdk="Microsoft.NET.Sdk.Web">

  <PropertyGroup>
    <TargetFramework>netcoreapp3.1</TargetFramework>
    <RootNamespace>test_project</RootNamespace>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="3.1.4" />
    <PackageReference Include="Microsoft.AspNetCore.Identity.EntityFrameworkCore" Version="3.1.7" />
    <PackageReference Include="Microsoft.AspNetCore.Identity.UI" Version="3.1.7" />
    <PackageReference Include="Microsoft.EntityFrameworkCore" Version="3.1.7" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="3.1.7">
      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
      <PrivateAssets>all</PrivateAssets>
    </PackageReference>
    <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="3.1.7">
      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
      <PrivateAssets>all</PrivateAssets>
    </PackageReference>
    <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
    <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="3.1.4" />
    <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL.Design" Version="1.1.0" />
  </ItemGroup>
</Project>

As you can see, the Microsoft.VisualStudio.Web.CodeGeneration.Design is the first in the list. However, when I try to run any scaffolder from the dotnet aspnet-codegenerator tool (e.g.: dotnet aspnet-codegenerator identity -h), I get the following message:

No code generators are available in this project.Add Microsoft.VisualStudio.Web.CodeGeneration.Design package to the project as a NuGet package reference.

Even if I specify the .csproj file with the -p flag, I still get the same message. While doing some research, I found this Issue in the repo, but it’s a different thing: the OP was trying to add the scaffolder to a .NET Core App 3.0 using the 3.1 scaffolder version.

I’m using dotnet 3.1.401 on Xubuntu 20.04.

Any thoughts? Thank you in advance.

Steps to reproduce:

• Install latest dotnet through MS repos
• dotnet tool install dotnet-aspnet-codegenerator --version 3.1.4
• dotnet new mvc
• dotnet add package Microsoft.VisualStudio.Web.CodeGeneration.Design -v 3.1.4 && dotnet restore && dotnet build
• dotnet aspnet-codegenerator identity -h

Expected behaviour:

• The Scaffolding tool should at least show any helpful information about the scaffolder

Actual behaviour:

• It shows the following message, even after adding the referred NuGet Package to the project: No code generators are available in this project. Add Microsoft.VisualStudio.Web.CodeGeneration.Design package to the project as a NuGet package reference.

Additional information about the project being scaffolded, such as:

Target framework(s): netcoreapp3.1

Package version of Microsoft.AspNetCore.App or Microsoft.AspNetCore.All (if applicable):

Package version of Microsoft.VisualStudio.Web.CodeGeneration.Design - this may be added to your project by scaffolding: 3.1.4, actually this problem can be reproduced even with the 3.1.3 version of it.

[deepchoudhery]

Hey all, @rhaynes123 @jonathan-daniel @cezarlamann @sanjitn @mtausig @MadeleineRoberts-WellSky @gustavohrgomes @stephen-innotek @lctx @iBolski @KilianKilmister @NorbiPeti

I have a fix for this issue out with a new 3.1.5 and 5.0.2 package out. Use dotnet tool update dotnet-aspnet-codegenerator -g --version 3.1.5/5.0.2 depending on if you are targeting .netcoreapp3.1 or net5.0. I would like it if someone could confirm the fix before I close the issue.

You will also need to update the Microsoft.VisualStudio.Web.CodeGeneration.Design package as well.

Apologize for the lengthy delay on this fix and appreciate all the feedback.

[mtausig]

Since @mwdmwd was able to find the root cause for the problem, I was successful with the following workaround (using Ubuntu 18.04 and .NET 5.0):

Create a dummy vfat filesystem:

dd if=/dev/zero of=/tmp/mynuget bs=1024k count=2000
mkfs.vfat /tmp/mynuget

Mount it in place of your nuget directory:

sudo mount -o uid=myuser,gid=myuser -t vfat /tmp/mynuget /home/myuser/.nuget

Then, after running dotnet restore the scaffolding works as expected.