Add an overload for IWebHostBuilder.Configure that takes in AssemblyName

[fitdev]

Is your feature request related to a problem? Please describe.

I am trying to create an internal library-based framework for authoring "hosted" apps, including ASP.NET apps. As such, I am not relying on the Startup class approach and instead I am following your guidelines for Startup-less configuration.

The problem comes if this configuration is split across several assemblies. In my case, there would be a "top-most" assembly with controllers and views, which would depend on other assemblies that are responsible for configuring ASP.NET. Turns out that routing does not work properly if IWebHostBuilder.Configure is called from other assembly (that does not contain controllers and actions).

Describe the solution you'd like

Ideally, it would be really nice if there was a mechanism to clearly provide all controller and action (and possibly other endpoint) "sources" as part of configuration process, perhaps as an overload of IWebHostBuilder.Configure accepting either a single AssemblyName as a string, or better yet an params? array of assembly names that should be looked in for relevant types (controllers, etc.).

[Tratcher]

Turns out that routing does not work properly if IWebHostBuilder.Configure is called from other assembly (that does not contain controllers and actions). @rynowak this is because MVC/routing depends on AppName for discovering controllers, right? And AppName is set based on the caller of Configure.

[davidfowl]

This has actually been broken since inception. Hosting tries to deduce the "application assembly" from the Startup class or the class that contains the Configure delegate, dupe of #7315.

We shouldn't be adding anything to hosting here, this is mainly about controller discovery and there are ways to explicitly add assemblies (https://docs.microsoft.com/en-us/aspnet/core/mvc/advanced/app-parts?view=aspnetcore-2.2).

Going forward we'll need to decide what our defaults are.

[mkArtakMSFT]

@davidfowl is there any other action pending here? Should this be cloased?

[davidfowl]

Closed.