How to create custom StaticFileMiddleware and redirect request to needed folder - middleware

Question

My site with Asp.Net Core 6 hes custom root folder for static files, different from folders with configuration, folders with Program.cs/vb, folders with View, folders with Area, folders with Controllers.
Parts of static files from this custom root working fine, but other static files don't working.
I try to intercept request to static files and manually redirect all request to my root folder with static files.
I write this code for this interception.
App.Use(Async Function(context, [next])
Dim CurrentEndpoint = context.GetEndpoint()
If (CurrentEndpoint Is Nothing) Then
Debug.WriteLine($"RequestPath {context.Request.Path} endpoint nothing.")
Dim StaticOptions As StaticFileOptions = New StaticFileOptions With {.FileProvider = New PhysicalFileProvider(Builder.Configuration("StaticFilesRoot"))}
Dim Opt As IOptions(Of StaticFileOptions) = Options.Create(StaticOptions)
Dim StaticMiddleware = New StaticFileMiddleware(
Async Function()
Await [next](context)
End Function,
Environment,
Opt.Value,
LoggerFactory)
Else
Await [next](context)
End If
End Function)
But my attempt to intercept "wrong" request and manually redirect it to needed folder is failed. Because I maybe made mistake to create StaticFileMiddleware.
Microsoft.AspNetCore.Hosting.Diagnostics: Information: Request starting HTTP/2 GET https://localhost:7168/scripts/script.js - -
RequestPath /scripts/script.js endpoint nothing.
Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware: Error: An unhandled exception has occurred while executing the request.
System.InvalidCastException: Unable to cast object of type 'Microsoft.AspNetCore.Builder.StaticFileOptions' to type 'Microsoft.Extensions.Options.IOptions`1[Microsoft.AspNetCore.Builder.StaticFileOptions]'.
at FrontEnd.Program._Closure$__12-0._Lambda$__10(HttpContext context, RequestDelegate next) in G:\Projects\CryptoChestMax\FrontEnd\FrontEndCode\Program.vb:line 256
at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)
Unfortunately, I can not understand what I doing wrong and what cast is not valid. If I try to create custom middleWare in debugger than there are not error, but attempt to processing request with my new StaticMiddleware get me error.
What wrong in my StaticMiddleware?

Answer 1

In current question this is my mistake with Root for StaticHtmlFiles, but my way to detection error can be helpful to any programmer.
I have create this Route Analyzer and finally understand that I have wrong variables loaded as Root for static files.
'Route anylizer
App.Use(Async Function(context As HttpContext, NextRequestDelegate As RequestDelegate)
Dim CurrentEndpoint = context.GetEndpoint()
If (CurrentEndpoint Is Nothing) Then
Debug.WriteLine($"RequestPath {context.Request.Path} endpoint nothing.")
Dim StaticOptions As StaticFileOptions = New StaticFileOptions With {.FileProvider = New PhysicalFileProvider(Builder.Configuration("StaticFilesRoot"))}
Dim Opt As IOptions(Of StaticFileOptions) = Options.Create(StaticOptions)
Dim NewEnvironment As IWebHostEnvironment = Environment
NewEnvironment.ContentRootPath = Builder.Configuration("StaticFilesRoot")
NewEnvironment.WebRootPath = Builder.Configuration("StaticFilesRoot")
Dim StaticMiddleware = New StaticFileMiddleware(
Async Function()
'Await NextRequestDelegate(context)
Dim StaticFile As IFileInfo = Opt.Value.FileProvider.GetFileInfo(context.Request.Path)
If Not StaticFile.Exists Then
Await context.Response.WriteAsync("File is nothing")
Else
Await context.Response.SendFileAsync(StaticFile)
End If
End Function,
NewEnvironment,
Opt,
LoggerFactory)
Await StaticMiddleware.Invoke(context)
Else
Debug.WriteLine($"Endpoint: {CurrentEndpoint.DisplayName}")
Dim Endpoint As RouteEndpoint = TryCast(CurrentEndpoint, RouteEndpoint)
Debug.WriteLine($"RoutePattern: {Endpoint?.RoutePattern.RawText}")
For j As Integer = 0 To CurrentEndpoint.Metadata.Count - 1
Debug.WriteLine($"Endpoint Metadata {j}: {CurrentEndpoint.Metadata(j)}")
Next
Await NextRequestDelegate(context)
End If
End Function)
And anybody can create custom message, custom code or custom header for missing files by this way