peterldowns / localias

custom local domain aliases for local dev servers
MIT License
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fix: smarter host IP determination for mDNS #38

Closed peterldowns closed 3 days ago

peterldowns commented 3 days ago

Serving .local aliases over mDNS requires broadcasting the IP address of the host machine, so that other devices on the network can connect to it. Previous to this PR, localias would do lookups by trying to lookup {hostname}.local. As reported in https://github.com/peterldowns/localias/issues/34, and previously in https://github.com/peterldowns/localias/issues/20 and https://github.com/peterldowns/localias/issues/21, this had a variety of issues and did not work consistently.

This PR attemtps to fix this problem once and for all by finding the host's IP by iterating through the network interfaces and looking for non-loopback IPV4 addresses. I tested that this fixes the problem reported in #34 by manually setting my hostname to something.fritz.box, seeing that localias would fail to determine the IP address, then running this code and seeing that it worked correctly.

In addition to the IPV4 addresses that are found, this code also broadcasts 127.0.0.1 and ::1 so that DNS requests on macOS respond instantly. For some reason, if an IPV6 address is not included in the mDNS response, running curl myhost.local will always have a 5-6 second delay on macOS. I can't explain it but I have a workaround.