charts/snowplow-iglu-server: add ingress tls override (closes #351)

[Ian Arsenault (ianarsenault)]

This PR brings iglu-server chart in parity with service-deployment and common chart to support supplying an already existing TLS K8s Secret

Existing deployments are left as is, future deployments can supply a tlsSecretName with the ingress configuration.

Validation

Existing behaviour — no tlsSecretName (unchanged)

helm template iglu snowplow-iglu-server \
  --set service.config.env.ACCEPT_LIMITED_USE_LICENSE=yes \
  --set 'service.ingress.ingress-01.hostname=iglu\.example\.com' \
  -s templates/iglu-ingress.yaml -s templates/certificate.yaml

# Source: snowplow-iglu-server/templates/iglu-ingress.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: iglu-app
spec:
  ingressClassName: traefik
  tls:
  - hosts:
      - "iglu.example.com"
    secretName: iglu.example.com-tls        # <-- unchanged default
  rules:
    - host: "iglu.example.com"
      ...
---
# Source: snowplow-iglu-server/templates/certificate.yaml
apiVersion: cert-manager.io/v1
kind: Certificate                            # <-- still created
metadata:
  name: iglu.example.com
spec:
  secretName: iglu.example.com-tls
  issuerRef:
    name: "letsencrypt"
    kind: "ClusterIssuer"
  commonName: "iglu.example.com"
  dnsNames:
  - "iglu.example.com"

New — tlsSecretName supplied

helm template iglu snowplow-iglu-server \
  --set service.config.env.ACCEPT_LIMITED_USE_LICENSE=yes \
  --set 'service.ingress.ingress-01.hostname=iglu\.example\.com' \
  --set 'service.ingress.ingress-01.tlsSecretName=wildcard-example-com-tls' \
  -s templates/iglu-ingress.yaml

# Source: snowplow-iglu-server/templates/iglu-ingress.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: iglu-app
spec:
  ingressClassName: traefik
  tls:
  - hosts:
      - "iglu.example.com"
    secretName: wildcard-example-com-tls    # <-- override applied
  rules:
    - host: "iglu.example.com"
      ...

No cert-manager Certificate is rendered for that host:

helm template iglu snowplow-iglu-server \
  --set service.config.env.ACCEPT_LIMITED_USE_LICENSE=yes \
  --set 'service.ingress.ingress-01.hostname=iglu\.example\.com' \
  --set 'service.ingress.ingress-01.tlsSecretName=wildcard-example-com-tls' \
  | grep "kind: Certificate" || echo "no Certificate rendered"
# -> no Certificate rendered