Add TLS Support for Metrics Server

[eanveden]

What would you like to be added: I would like to request the addition of TLS support for the metrics server in ExternalDNS. Currently, there is no mention of HTTPS support in the documentation, and upon reviewing the code, I did not find any indication of TLS support for the /metrics or /healthz route. See https://github.com/kubernetes-sigs/external-dns/blob/7f3c10d65297ec1c4bcc8dd6f88c189b7f3e80d0/main.go#L495

Why is this needed: We have strict compliance requirements that mandate all E2E communications to services should be done over HTTPS. This includes metrics endpoints.

[MikeKlebolt]

Hello, our organization has a strict TLS requirement. Can we please get this looked into?

[Peac36]

/assign

[Raffo]

Could you explain me why you can't put a sidecar "in front" or external dns and use that to handle ssl termination? This is a widespread approach to such type of requirements and wouldn't require any modification to external dns.

[eanveden]

You are suggesting a workaround, is that going to be the accepted way of getting full TLS support for external DNS? Should we consider adding support for that sidecar in the helm chart?

[szuecs]

@eanveden I think the suggestion is to create whatever you need for this outside of this repository. Thanks for your understanding.

[eanveden]

@szuecs we will go with the sidecar approach, thx.

[eanveden]

Closing this