ingress: Add option to assign VIP as externalIP

Some CNIs support the advertisement of service IPs into BGP, which may
provide an alternative to managing the VIP as an interface on the host.

This change adds an option to assign the ingress VIP as an externalIP to
the ingress service. For example:

    network:
      vip:
        manage: false
        addr: 172.18.0.1/32           # (with or without subnet mask)
        assign_as_external_ip: true

Change-Id: I1eeb07a1f94ef8efcb21f3373e0d5f86be725b33

ingress/Chart.yaml

@@ -15,7 +15,7 @@ apiVersion: v1
 appVersion: v0.42.0
 description: OpenStack-Helm Ingress Controller
 name: ingress
-version: 0.2.5
+version: 0.2.6
 home: https://github.com/kubernetes/ingress
 sources:
   - https://github.com/kubernetes/ingress

ingress/templates/service-ingress.yaml

@@ -27,6 +27,10 @@ metadata:
 spec:
 {{- if and .Values.network.host_namespace .Values.network.vip.manage }}
   clusterIP: None
+{{- end }}
+{{- if .Values.network.vip.assign_as_external_ip }}
+  externalIPs:
+    - {{ (.Values.network.vip.addr | split "/")._0 }}
 {{- end }}
   ports:
   - name: http

ingress/values.yaml

@@ -141,6 +141,9 @@ network:
     interface: ingress-vip
     addr: 172.18.0.1/32
     keepalived_router_id: 100
+    # Use .network.vip.addr as an external IP for the service
+    # Useful if the CNI or provider can set up routes, etc.
+    assign_as_external_ip: false
   ingress:
     annotations:
       # NOTE(portdirect): if left blank this is populated from

releasenotes/notes/ingress.yaml

@@ -9,4 +9,5 @@ ingress:
   - 0.2.3 Uplift ingress to 0.42.0
   - 0.2.4 Update htk requirements
   - 0.2.5 Migrate Ingress resources to networking.k8s.io/v1
+  - 0.2.6 Add option to assign VIP as externalIP
 ...