viking-test-app supports BackendConfig.

charts/viking-test-app/templates/backendconfig.yaml

+{{- range $name, $app := .Values.apps -}}
+{{- if $app.config -}}
+apiVersion: "ingress.varnish-cache.org/v1alpha1"
+kind: BackendConfig
+metadata:
+  name: {{ $name }}-svc-cfg
+  labels:
+    app.kubernetes.io/name: {{ $name }}-svc-cfg
+    app.kubernetes.io/component: ingressBackendConfig
+    {{- include "viking-ingress.labels" $ | nindent 4 }}
+spec:
+  services:
+    - {{ $name }}-svc
+
+  {{ toYaml $app.config | nindent 2 }}
+---
+{{- end -}}
+{{- end -}}

charts/viking-test-app/values.yaml

@@ -13,6 +13,9 @@ apps: {}
     # servicePort: 80
     # targetPort: 80
 
+    # If non-empty, contains a BackendConfig for this app.
+    # config: {}
+
 ingress:
   # Must match the Ingress class observed by the controller.
   class: "varnish"