Supporting template evaluation in ingress hosts

[jkroepke]

Overview

Hi, I would like to use dex as part of a umbrella helm chart. For the user experience, there is currently global (sub)domain configuration across all helm charts and sub-charts are able to use the helm evaluation function to build a hostname. After merging the PR, I could use somelike like this in my value yaml

dex:
  ingress:
    annotations:
      cert-manager.io/cluster-issuer: letsencrypt
    hosts:
    - host: 'auth.{{ $.Values.global.domain }}'
      paths:
      - path: /
         pathType: Prefix
    tls:
    - secretName: tls-secret-dex
      hosts:
      - 'auth.{{ $.Values.global.domain }}'

And user only needs to define --set global.domain=example.com.

Note, w/o this, end users needs to pass the whole list item, since helm is not able to merge lists.

What this PR does / why we need it

Special notes for your reviewer

kube-prometheus-stack and grafana helm chart are supporting this scenario, too

Checklist

• [x] Change log updated in Chart.yaml (see the contributing guide for details)
• [x] Chart version bumped in Chart.yaml (see the contributing guide for details)
• [x] Documentation regenerated by running make docs

[jkroepke]

@sagikazarmark I'm aware pinging maintainers is not such a good thing! I would highly appreciate some feedback here.

[sagikazarmark]

@jkroepke I maintain dozens, if not hundreds of projects (which means I get at least a hundred emails from GitHub daily). Pinging me is the ONLY way to get my attention. Don't feel bad about that (but also don't take it personally if I don't answer for a long time).

I'm generally not a huge fan of this pattern, but it's a small change, low maintenance and may actually be more popular than I would have thought (didn't know prometheus uses this pattern), so I think it's okay to add.

[jkroepke]

Thanks @sagikazarmark, I additionally run make docs

[jkroepke]

@sagikazarmark are the actions failures related to this change? maybe bump to helm/kind-action@v1.5.0 would help here.

[jkroepke]

@sagikazarmark is there anything what I can do to unblock this here?

[jkroepke]

@sagikazarmark how we can procceed here? Removing old kubernetes versions may be the best option here. (1.19+ is green)

[sagikazarmark]

Can you please rebase @jkroepke ?

[jkroepke]

@sagikazarmark rebased