Program.cs

usingMicrosoft.AspNetCore.Hosting.Server.Features;
usingMicrosoft.AspNetCore.Hosting.Server;

varapp=WebApplication.Create();
app.UseMiddleware<AddressesMiddleware>();
app.Run();

publicclassAddressesMiddleware
{
IServer_server;

IReadOnlyCollection<string>_addresses;

publicAddressesMiddleware(RequestDelegatenext,IServerserver)
{
_server=server;
}

publicasyncTaskInvoke(HttpContextcontext)
{
varstr=string.Empty;

// We cache the result because the addresses are not going to change. 
// Remember middlewares are singletons, so we can just do this simple check. 
if(_addresses==null)
{
varaddress=_server.Features.Get<IServerAddressesFeature>();
_addresses=address.Addresses.ToList();
}

foreach(varain_addresses)
{
str+=$"{a}\n";
}

awaitcontext.Response.WriteAsync(str);
}
}