InvalidOperationException: The SPA default page middleware could not return the default page '/index.html' because it was not found, and no other middleware handled the request.

Question

InvalidOperationException: The SPA default page middleware could not return the default page '/index.html' because it was not found, and no other middleware handled the request.

sporifolous opened this issue 5 years ago · 3 comments

After running a clean install with dotnet new vue -o VueStarter then running dotnet run the project builds and runs, but navigating to localhost:5000 results in an InvalidOperationException.

InvalidOperationException: The SPA default page middleware could not return the default page '/index.html' because it was not found, and no other middleware handled the request. Microsoft.AspNetCore.SpaServices.SpaDefaultPageMiddleware+<>c__DisplayClass0_0.<Attach>b__1(HttpContext context, Func<Task> next) Microsoft.AspNetCore.Builder.UseExtensions+<>c__DisplayClass0_1.<Use>b__1(HttpContext context) Microsoft.AspNetCore.Builder.UseExtensions+<>c__DisplayClass0_2.<Use>b__2() Microsoft.AspNetCore.SpaServices.SpaDefaultPageMiddleware+<>c__DisplayClass0_0.<Attach>b__0(HttpContext context, Func<Task> next) Microsoft.AspNetCore.Builder.UseExtensions+<>c__DisplayClass0_1.<Use>b__1(HttpContext context) VueCliMiddleware.VueCliMiddlewareExtensions+<>c__DisplayClass5_1.<CreateProxyRequestDelegate>b__2(HttpContext context) Microsoft.AspNetCore.Routing.EndpointMiddleware.Invoke(HttpContext httpContext) Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)

Answer 1 · 2019-11-06T21:40:53.000Z

Hi, thank you for reporting the issue! I was able to reproduce it, now I have to understand why VueCliMiddleware cannot locate the index file. I will investigate the issue tomorrow.

When you start the app from VS Code or VS 2019 it works as expected.

Answer 2 · 2019-11-06T22:09:15.000Z

The problem is line 64 in Startup.cs:
npmScript: (System.Diagnostics.Debugger.IsAttached) ? "serve" : null,
you can set it in the following way:
npmScript: env.IsDevelopment() ? "serve" : null,.

When there's no debugger attached, client app does not start.

Answer 3 · 2019-11-06T22:09:54.000Z

Yep, running in debug mode from VS 2019 works great.

This is exactly what I ended up doing to get it working. Glad to hear this is the recommended fix.

Thanks for getting back to me so quickly!