With .NET 7.0 SDK, I cannot create .NET 6.0 web project, the target net6.0 can't be found.

[Andy-Win]

Repro steps:

1. Install latest main build VS from main-32123.28 (Run preinstall command first)
2. Download .NET 7 SDK(7.0.100-alpha.1.22071.3) from main branch of https://github.com/dotnet/installer
3. Open VS, apply feed: https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet7/nuget/v3/index.json
4. Open Command Prompt and run"dotnet new mvc -f net6.0 -o Mvc60" to create ASP.NET Core 6.0 MVC project.

Expected Result
The project should be created successfully.

Actual Result:

dotnet --info

[WenJunJi01]

This issue only occurs on web projects, and creating a .NET 6.0 console/classlib/wpf/winforms project can succeed.

Dotnet info:

[marcpopMSFT]

From Nicole, this is only a web template issue so routing to aspnet
For Andy’s [New]#13105, it only occurs on web projects, and creating a .NET 6.0 console/classlib/wpf/winforms project can succeed

[mkArtakMSFT]

@dougbu any idea why this may be the case?

[mkArtakMSFT]

Also tagging @joeloff in case you have thoughts too

[dougbu]

@wtgodbe wasn't there an issue in earlier 7.0 SDKs relating to net6.0 templates❔

[wtgodbe]

There was an issue a couple weeks ago with net7.0 templates in 7.0 SDKs, before the templates were added, but I don't remember 7.0 SDKs having problems with net6.0, that surprises me. I can try to repro after lunch

[mkArtakMSFT]

@wtgodbe do you have any updates here?

[wtgodbe]

I've confirmed that it repros on the SDK mentioned, but not on an older SDK from October, so something changed recently to introduce this. I'm still investigating

[wtgodbe]

I believe this is related to dotnet/installer#12946, the error doesn't repro on SDKs before we added the net7.0 templates. @dsplaisted do you know where in dotnet/sdk the error described is getting triggered?

[wtgodbe]

Also adding @vlada-shubina for the above question

[dsplaisted]

I think this would be the expected behavior if you just installed the .NET 7 SDK standalone. For the mvc template (and most or all of the ASP.NET ones), you only get the templates for the version of the SDK you have installed. So if you wanted the .NET 6 templates you would also have to install the .NET 6 SDK.

With Visual Studio it works a bit different, so it's possible there's a bug in the setup authoring. But I think the way it's supposed to work in Visual Studio is that you wouldn't get the templates for .NET 6 unless you installed the .NET 6 runtime (as you wouldn't by default be able to run a project targeting 6.0 without the 6.0 runtime).

What versions of the .NET SDK and runtimes are installed? Can you paste the output of dotnet --info from a repro machine?

Also adding @joeloff as he is more familiar with the VS setup authoring.

[MichalPavlik]

I was debugging the templating engine and there is the ApplyFilters method, where the engine is trying to find a match for parameters. I see it loads templates for all installed versions, but for some reason, in case of the mvc (and maybe other web templates) I can't see loaded templates for version 6. Need more time to investigate.

[joeloff]

For VS we insert multiple installers for the templates, e.g. for the 6.0 SDK there would be the 6.0 copies of the 5.0, 3.1 templates. These typically only ship with VS.

[joeloff]

I was looking at a local build of the 6.0 templates. The installer we generate for VS is building items that are still marked as 6.0.0-rc2 and some that are marked as 6.0.1.

[joeloff]

@dsplaisted are these values correct? https://github.com/dotnet/installer/blob/1a828392f79d5d7a391b2a387e962e204fb245cd/eng/Versions.props#L109

[dsplaisted]

@joeloff No, they should ideally be updated to 6.0.100 or whatever the latest version available for the 6.0 band is. For example: https://github.com/dotnet/installer/blob/release/6.0.1xx/eng/Versions.props#L34

[joeloff]

Right, but the ASP.NET ones are tracking runtime versions so those should be 6.0.1 or 6.0.2 I think

[wtgodbe]

It sounds like we should update https://github.com/dotnet/installer/blob/1a828392f79d5d7a391b2a387e962e204fb245cd/eng/Versions.props#L109-L111, but if that was the issue, wouldn't 5.0 Asp.Net templates be broken too because of line 110?

[joeloff]

It sounds like we should update https://github.com/dotnet/installer/blob/1a828392f79d5d7a391b2a387e962e204fb245cd/eng/Versions.props#L109-L111, but if that was the issue, wouldn't 5.0 Asp.Net templates be broken too because of line 110?

I'm not sure

[wtgodbe]

Opened dotnet/installer#13113 to see if it helps

[wtgodbe]

dotnet/installer#13113 didn't do the trick - @MichalPavlik were you able to get anywhere in your investigation?

[MichalPavlik]

The package for net6 is loaded and scanned for templates, so it seems they are filtered out later in the process. I'm narrowing down the issue slowly and I hope I will get the answer today.

[MichalPavlik]

I believe I found the root cause. There is a deduplication step which basically adds discovered templates to dictionary with template's identity as a key. Templates for net7.0 have still same identity name, so they replaced net6.0 templates.

aspnetcore/src/ProjectTemplates/Web.ProjectTemplates/content/StarterWeb-CSharp/.template.config/template.json

Line 13 in fca7c73

"identity": "Microsoft.Web.Mvc.CSharp.6.0",

Changing identity to reflect new version should help. I can create PR for you, but I'm not sure this is only thing you want to modify. I see there is also thirdPartyNotices field with probably old link.

[wtgodbe]

Thanks! Looks like we should have updated that at the same time we updated branding - I'll push a PR for it & update our documentation.

[mkArtakMSFT]

@wtgodbe is this blocked on dotnet/installer#13125?

[wtgodbe]

@wtgodbe is this blocked on dotnet/installer#13125?

Yes, and that's blocked on dotnet/sdk#23597, which should get in once CI passes

[dsplaisted]

The PRs have all merged, so hopefully this is now fixed.

[wtgodbe]

Confirmed that this is now fixed

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