启动 Angular + ASP.Net 核心应用程序导致 'The SPA default page middleware could not return the default page '/index.html''

Question

我有兴趣在 Ubuntu Linux VPS 上部署带有 Angular 前端的 ASP.NET 核心应用程序。我正在使用 Nginx-Proxy，但这应该不会对此问题产生任何影响（它按预期工作）。我面临的问题可能是由于根文件夹和 linux 执行根路径。

这是什么问题？

从文件夹内启动我的应用程序时，.dll 文件位于 dotnet MyApp.dll 中，它工作得很好，也可以通过浏览器从外部访问。

但是当用 daemon/systemd 和 ExecStart=/usr/bin/dotnet /home/MyApp/MyApp.dll 执行时，它 returns 出现以下错误。从根文件夹 (~#) 使用相同的命令启动时也会发生这种情况。

fail: Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware[1]
      An unhandled exception has occurred while executing the request.
      System.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.
      Your application is running in Production mode, so make sure it has been published, or that you have built your SPA manually. Alternatively you may wish to switch to the Development environment.

         at Microsoft.AspNetCore.SpaServices.SpaDefaultPageMiddleware.<>c__DisplayClass0_0.<Attach>b__1(HttpContext context, Func`1 next)
         at Microsoft.AspNetCore.Builder.UseExtensions.<>c__DisplayClass0_1.<Use>b__1(HttpContext context)
         at Microsoft.AspNetCore.Builder.UseExtensions.<>c__DisplayClass0_2.<Use>b__2()
         at Microsoft.AspNetCore.SpaServices.SpaDefaultPageMiddleware.<>c__DisplayClass0_0.<Attach>b__0(HttpContext context, Func`1 next)
         at Microsoft.AspNetCore.Builder.UseExtensions.<>c__DisplayClass0_1.<Use>b__1(HttpContext context)
         at Microsoft.AspNetCore.Routing.EndpointMiddleware.Invoke(HttpContext httpContext)
         at Microsoft.AspNetCore.Routing.EndpointRoutingMiddleware.Invoke(HttpContext httpContext)
         at Microsoft.AspNetCore.StaticFiles.StaticFileMiddleware.Invoke(HttpContext context)
         at Microsoft.AspNetCore.HttpsPolicy.HttpsRedirectionMiddleware.Invoke(HttpContext context)
         at Microsoft.AspNetCore.HttpsPolicy.HstsMiddleware.Invoke(HttpContext context)
         at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware.Invoke(HttpContext context)
fail: Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware[3]
      An exception was thrown attempting to execute the error handler.
      System.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.
      Your application is running in Production mode, so make sure it has been published, or that you have built your SPA manually. Alternatively you may wish to switch to the Development environment.

         at Microsoft.AspNetCore.SpaServices.SpaDefaultPageMiddleware.<>c__DisplayClass0_0.<Attach>b__1(HttpContext context, Func`1 next)
         at Microsoft.AspNetCore.Builder.UseExtensions.<>c__DisplayClass0_1.<Use>b__1(HttpContext context)
         at Microsoft.AspNetCore.Builder.UseExtensions.<>c__DisplayClass0_2.<Use>b__2()
         at Microsoft.AspNetCore.SpaServices.SpaDefaultPageMiddleware.<>c__DisplayClass0_0.<Attach>b__0(HttpContext context, Func`1 next)
         at Microsoft.AspNetCore.Builder.UseExtensions.<>c__DisplayClass0_1.<Use>b__1(HttpContext context)
         at Microsoft.AspNetCore.Routing.EndpointMiddleware.Invoke(HttpContext httpContext)
         at Microsoft.AspNetCore.Routing.EndpointRoutingMiddleware.Invoke(HttpContext httpContext)
         at Microsoft.AspNetCore.StaticFiles.StaticFileMiddleware.Invoke(HttpContext context)
         at Microsoft.AspNetCore.HttpsPolicy.HttpsRedirectionMiddleware.Invoke(HttpContext context)
         at Microsoft.AspNetCore.HttpsPolicy.HstsMiddleware.Invoke(HttpContext context)
         at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware.HandleException(HttpContext context, ExceptionDispatchInfo edi)
fail: Microsoft.AspNetCore.Server.Kestrel[13]
      Connection id "0HMA8CR3IGQIJ", Request id "0HMA8CR3IGQIJ:00000002": An unhandled exception was thrown by the application.
      System.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.
      Your application is running in Production mode, so make sure it has been published, or that you have built your SPA manually. Alternatively you may wish to switch to the Development environment.

         at Microsoft.AspNetCore.SpaServices.SpaDefaultPageMiddleware.<>c__DisplayClass0_0.<Attach>b__1(HttpContext context, Func`1 next)
         at Microsoft.AspNetCore.Builder.UseExtensions.<>c__DisplayClass0_1.<Use>b__1(HttpContext context)
         at Microsoft.AspNetCore.Builder.UseExtensions.<>c__DisplayClass0_2.<Use>b__2()
         at Microsoft.AspNetCore.SpaServices.SpaDefaultPageMiddleware.<>c__DisplayClass0_0.<Attach>b__0(HttpContext context, Func`1 next)
         at Microsoft.AspNetCore.Builder.UseExtensions.<>c__DisplayClass0_1.<Use>b__1(HttpContext context)
         at Microsoft.AspNetCore.Routing.EndpointMiddleware.Invoke(HttpContext httpContext)
         at Microsoft.AspNetCore.Routing.EndpointRoutingMiddleware.Invoke(HttpContext httpContext)
         at Microsoft.AspNetCore.StaticFiles.StaticFileMiddleware.Invoke(HttpContext context)
         at Microsoft.AspNetCore.HttpsPolicy.HttpsRedirectionMiddleware.Invoke(HttpContext context)
         at Microsoft.AspNetCore.HttpsPolicy.HstsMiddleware.Invoke(HttpContext context)
         at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware.Invoke(HttpContext context)
      --- End of stack trace from previous location ---
         at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware.HandleException(HttpContext context, ExceptionDispatchInfo edi)
         at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)

许多其他线程在 Startup.cs 中提到了这段话，但保持不变：

services.AddSpaStaticFiles(configuration =>
            {
                configuration.RootPath = "ClientApp/dist";
            });

Answer 1

问题是由于 Content-Root/Working-Directory 从其文件夹外部（例如 systemd）执行 .dll 文件时引起的。 通过将 WorkingDirectory=/path/to/app 添加到我的 systemd-service

解决了这个问题