I know that is located in HttpContext.Request.PathBase, however I need it to configure my cookie before I have any HttpContext (in Startup.cs).
My problem:
When devops configure application they have to set path twice. Once in IIS application (so hosting knows what should be served) and in my appsettings.json (so application knows where to set cookies - multiple instances can work on server). I would like to configure it once in IIS, and have config passed to my application.
You can check the environment variable ASPNETCORE_APPL_PATH. This is the variable AspNetCoreModule provides so that PathBase can be set correctly. See https://github.com/aspnet/IISIntegration/blob/df88e322cc5e52db3dbce4060d5bc7db88edb8e4/src/Microsoft.AspNetCore.Server.IISIntegration/WebHostBuilderIISExtensions.cs#L19
But what if you are using raw Kestrel?
Kestrel no longer directly supports base paths.
UsePathBase is still a thing, no?
This Environment Variable is only present if you are using the
OutOfProcesshosting model. If you are usingInProcessthe information is only present on theHttpRequest.PathBaseproperty.