How to add a minmal Webhost to a HostApplicationBuilder

[MarcusWichelmann]

Hi,

I'm building a CLI tool and use Host.CreateEmptyApplicationBuilder to configure a simple, empty HostApplicationBuilder with just some console logging and dependency injection. This works fine. I really don't need much for this application.

Now, for a single CLI command (one of many), I want to host a gRPC service. For this, I need to use ASP.Net Core. But I don't find a way to add a minimal Kestrel instance to my HostApplicationBuilder.

I don't want to use WebApplication.CreateBuilder to create a whole new WebApplicationBuilder because I'd have to add my dependencies again to that builder which would duplicate and complicate things. And I also cannot use WebApplicationBuilder for all cli commands, because this automatically registers some IHostedServices that I don't want to run with each command.

What I'm searching for: A way to add just the few dependencies I need for a Kestrel web server with gRPC support to an existing empty HostApplicationBuilder. I'd prefer a manual & declarative approach where I can explicitly decide myself, which services I want to include, because I don't need most of the things ASP.Net Core brings by default and want so safe some memory. IMHO, the default WebApplicationBuilder does way to much implicit magic that is hidden away in some internal classes that cannot be partially reused.

Do you have an idea, how this can be archieved?

[KennethHoff]

Would WebApplication.CreateEmptyBuilder() be helpful?

[MarcusWichelmann]

Thanks, WebApplication.CreateEmptyBuilder() goes into the right direction. Still I'd prefer to be able to add a webhost to an existing builder.