Import Cornerstone3D library in ASP.NET Core web application

Question

Premise: I have successfully integrated the legacy cornerstonehttps://github.com/cornerstonejs/cornerstone library into an ASP.NET Core 6.0 project.

Now I try to switch to cornerstone3D but it is a big challenge. I read the Migration Guides but I didn’t find any answer for my case.

However I try to import in my project cornerstone3D in the same way that I have done for the legacy cornerstone. So:

I have imported in my libs cornerstone3D via unpkg https://unpkg.com/@cornerstonejs/[email protected]. At the end I have cornerstone lib under wwwroot\lib\cornerstonejs\core.

In the legacy version of the library I have just to import cornerstone.min.js in this way to use the library in my html (razor) pages... and this works!

With the new version I don't really know how to perform the same action, or better to make available the library in my html pages. If I have understood cornerstone3D is distributed in 3 ways: cjs, esm, udm. I think the best for me is esm (ECMAScript) however I have also tried the others without success.

1. I try to import index.js or renderingengine.js but I face these issues, and I get this error

   Cannot use import statement outside a module

   and it's ok!

2. I fix this problem in this way, but I get many 404 errors like

   Failed to load resource: the server responded with a status of 404

   I think this is because import clause inside the library are written in this way (I don't want to say it is wrong I just want to say that my server cannot handle this syntax):

    import * as Enums from './enums'
   

   instead of './enums/index.js'

   or

    import eventTarget from './eventTarget'; 
   

   instead of './enums/index.js'

3. I have tried to fix this problem modifying my server, I write a dedicated middleware which can redirect the request to the correct path: in simple terms when request ask for ./enums response is ./enums/index.js

   Here is the code of the middleware just for completeness

   public class FileRedirectMiddleware
   {
       private readonly RequestDelegate _next;
       private readonly IWebHostEnvironment _webHostEnvironment;
   
       public FileRedirectMiddleware(RequestDelegate next, IWebHostEnvironment webHostEnvironment)
       {
           _webHostEnvironment = webHostEnvironment;
           _next = next;
       }
   
       public async Task Invoke(HttpContext context)
       {
           if (context.Request.Path.Value!.Contains("cornerstonejs") )
           {
               var fixpath = context.Request.Path.Value!.Replace("//", "/");
               fixpath = fixpath.Replace("/", "\\");
               fixpath = fixpath.TrimStart('\\');
   
               string path = Path.Combine(_webHostEnvironment.WebRootPath, fixpath);
               if (!File.Exists(path))
               {
                   if (Directory.Exists(path))
                   {
                       context.Response.Redirect(context.Request.Path + "/index.js");
                       return;
                   }
                   else
                   {
                       context.Response.Redirect(context.Request.Path + ".js");
                       return;
                   }
               }
           }
           await _next(context);
       }
   }
   

   and I have registered it in the message pipe

   var builder = WebApplication.CreateBuilder(args);
   
   // Add services to the container.
   builder.Services.AddControllersWithViews();
   
   var app = builder.Build();
   app.UseMiddleware<FileRedirectMiddleware>();
   // Configure the HTTP request pipeline.
   if (!app.Environment.IsDevelopment())
   {
       app.UseExceptionHandler("/Home/Error");
       app.UseHsts();
   }
   app.UseHttpsRedirection();
   app.UseStaticFiles();
   

   It doesn't work because I see that browser hangs indefinitely trying to load the page

4. I have tried, I'm ashamed of this because it’s really bad, to modify library just to see if the problem is in the middleware I have implemented, in order to have the correct paths in import directive but I get the same result: browser hangs indefinitely trying to load the page

In my opinion my approach is completely wrong. I ask if there is a proper way to import cornestone3D in an ASP.NET Core web application or if someone have faced the same issue and solved in some way.