Retiring the Microsoft.AspNetCore.SpaTemplates package (Aurelia/Knockout/Vue templates)

[SteveSandersonMS]

The Microsoft.AspNetCore.SpaTemplates package never shipped in the .NET Core SDK, and never reached an official level of support. The ASP.NET team's development resources are finite, and we think we can deliver more valuable features to ASP.NET developers by focusing elsewhere.

So:

• The Microsoft.DotNet.Web.Spa.ProjectTemplates package, containing Angular, React, and React+Redux templates, is not affected. This ships in the .NET Core SDK and is officially supported. We continue to invest development effort in this package. We can put more time and effort into these SPA templates now the effort isn't so spread out.
• If you have an existing Aurelia/Knockout/Vue project based on our SPA templates, you're not directly affected because these templates are only used to create new projects. You can continue building and shipping your app forever. Obviously we still support and enhance the underlying ASP.NET Core APIs (such as those in JavaScriptServices) that you are using.
• The Microsoft.AspNetCore.SpaTemplates package, containing Aurelia, Knockout, and Vue templates, continues to be available, but we'll no longer update it or work on issues related to it.
• We encourage enthusiastic community members to ship your own dotnet new templates. The dotnet new system is extensible for this exact reason. If you want to own the go-to Aurelia/Knockout/Vue project template, now's your chance! You could fork the ones from Microsoft.AspNetCore.SpaTemplates, or start from scratch depending on what you prefer.
• In the long term, if another JavaScript SPA framework becomes dominant, we will of course consider adding a template for it to the SDK templates package.

I know this will be irritating to some people, especially those who have worked on PRs for the Aurelia/Knockout/Vue templates. I'm sorry about that! I hope you can understand that our goal is to offer the overall maximum benefit for ASP.NET developers based on the resources available.

Discussion for this issue is at aspnet/JavaScriptServices#1522