My specific use case is performing client-side load-balancing against a headless service in Kubernetes. In a headless service, the cluster publishes a DNS record mapping e.g. my-svc.my-namespace.svc.cluster-domain.example to the IP addresses for each replica of the service. A client that wants to talk to the service resolves the DNS record to get the set of replica IPs, and selects the one it wants to send the request to. However, we can't just send the request to e.g. https://10.0.1.123/my-endpoint since the TLS cert is only issued for my-svc.my-namespace.svc.cluster-domain.example and not the individual pod IPs.

To make this work, cleanest way seems to be to rewrite the URI to include both the hostname and IP. I can then create a custom DNS resolver for the Hyper client which pull the IP out of the URI, and a custom servername resolver in hyper-rustls that pulls the hostname out.

djc requested a review from cpu 3 hours ago

Will take a look soon.

@djc should we cut a release for this?

I was defaulting to not doing so (proactively) unless the OP asks for it.

A release would be appreciated :)

A release would be appreciated :)

In progress: #270