--host and local dns names

[jbergstroem]

A common practice where I work to keep environments as similar as possible is to use hostnames to separate environments; for instance https://work.com for production, https://staging.work.com for a Q/A environment and https://dev.work.com for local development. These may be resolved via either /etc/hosts or a dns resolver. In this case, dev.work.com would resolve to 127.0.0.1 which is a local address, but treated by SvelteKit as external.

This could be seen as a minor inconvenience since opening 127.0.0.1 would work in most cases. It gets tricker once you start using csp or your own SSL certificates since both relies on what host is being used.

I would like to suggest a change to how Sveltekit sees as local by resolving what is passed to --host (should it not be an ip) and based on the result, use said host for either local or external when writing to console or using launch.

Thanks for your consideration.

[jbergstroem]

So, looking a bit closer into this; we are basically just looking at whatever (server.httpServer).address() returns (which already resolves the host).

Not sure if I am an exception case (read: relying on hostnames for locallys signed SSL certificates) so I'm not sure if a PR would be accepted where I just print "vite_config.server.host" (if set) instead of localhost?