ASP.NET Core 3.0 catch-all route unexpected behavior

[ExileLee]

Describe the bug

Recently i encounter some unexpected issue

I'm using ASP.NET Core 3.0 and i defined two routes in StartUp.cs

StartUp.cs

   app.UseEndpoints(endpoints =>
    {
        endpoints.MapControllerRoute(
            name: "file",
            pattern: "{controller=File}/folder/{*path}",
            new { Action = "Folder" });

        endpoints.MapControllerRoute(
            name: "default",
            pattern: "{controller=File}/{action=Index}/{filename}");
    });

FileController.cs

public class FileController : Controller
{
    public IActionResult Folder(string path)
    {
        return Ok(path);
    }

    public IActionResult Index(string filename)
    {
        return Ok(filename);
    }
}

request to file/folder/abc/abc i expected to match first route but the result was 404 not found

but if i changed order of route

   app.UseEndpoints(endpoints =>
    {
        endpoints.MapControllerRoute(
            name: "default",
            pattern: "{controller=File}/{action=Index}/{filename}");

        endpoints.MapControllerRoute(
            name: "file",
            pattern: "{controller=File}/folder/{*path}",
            new { Action = "Folder" });
    });

It work!

Expected behavior

My questing is why first version don't work if i defined {controller=File}/folder/{*path} on top

I thought it will check route table sequentially

[javiercn]

@ExileLee thanks for contacting us.

I believe with endpoint routing even "traditional" routes are not routed sequentially (@rynowak can correct me) but are treated in "precedence" order, that means, more specific routes like /literal/literal/literal take precedence over /literal/{parameter}/literal.

That said, I don't think why your first route wouldn't match.
@rynowak Thoughts? I don't see why the first route wouldn't match.

[ExileLee]

If i only confiure one route

   endpoints.MapControllerRoute(
            name: "file",
            pattern: "{controller=File}/folder/{*path}",
            new { Action = "Folder" });

it will match

but following code will end up 404 not found

        endpoints.MapControllerRoute(
            name: "file",
            pattern: "{controller=File}/folder/{*path}",
            new { Action = "Folder" });

        endpoints.MapControllerRoute(
            name: "default",
            pattern: "{controller=File}/{action=Index}/{filename}");

[rynowak]

This is definitely a bug. Adding additional routes shouldn't make something turn into a 404.

Here's a comparison:

Broken

Working

We're not building the same graph here depending on the ordering.