feat: add HOST config to control which network interface ld-relay binds to

brycefisher commented 6 months ago

Requirements

[ ] I have added test coverage for new or changed functionality
[ ] I have followed the repository's pull request submission guidelines
[ ] I have validated my changes against all supported platform versions

Describe the solution you've provided

By default, the existing behavior is preserved of binding all to network interfaces. However, if the config HOST is provided, ld-relay will attempt to bind that host on given PORT.

Describe alternatives you've considered

We could offer a boolean flag "BIND_LOCALHOST" or similar that would explicitly set the bind address to localhost:PORT. The provided option seemed more inline what I've seen in other projects, but I've no strong personal preference for either.

ALternatively we could allow users to specify a fully formed bind address including port and hostname in a single string. I don't like that option because we'd potentially break how folks configure how they instruct ld-relay where to run if they tried to provide both a fully formed address and a port. Keeping HOST and PORT distinct seems simpler to implement and reason about AFAICT.

Additional context

I'm not sure what this new config should be called 🤔

brycefisher commented 6 months ago

@cwaldren-ld is there anything special I need to do to run the existing tests? Is go test good enough to iterate locally? Apologies for missing the contribution guide! Feel free to point me at that.

cwaldren-ld commented 6 months ago

Hi @brycefisher , the guide is here: https://github.com/launchdarkly/ld-relay/blob/v8/CONTRIBUTING.md

launchdarkly / ld-relay

feat: add HOST config to control which network interface ld-relay binds to #354