Support specifying affinity in Helm chart (#1962)

Author: sidprak

config/charts/knative-operator/templates/operator.yaml

@@ -71,16 +71,10 @@ spec:
         {{ toYaml .Values.knative_operator.operator_webhook.podAnnotations }}
       {{- end }}
     spec:
-      # To avoid node becoming SPOF, spread our replicas to different nodes.
+      {{- if .Values.knative_operator.operator_webhook.affinity }}
       affinity:
-        podAntiAffinity:
-          preferredDuringSchedulingIgnoredDuringExecution:
-          - podAffinityTerm:
-              labelSelector:
-                matchLabels:
-                  app: operator-webhook
-              topologyKey: kubernetes.io/hostname
-            weight: 100
+      {{- toYaml .Values.knative_operator.operator_webhook.affinity | nindent 8 }}
+      {{- end }}
       {{- if and .Values.knative_operator.operator_webhook.securityContext }}
       securityContext:
         {{ toYaml .Values.knative_operator.operator_webhook.securityContext }}
@@ -6357,6 +6351,10 @@ spec:
         {{ toYaml .Values.knative_operator.knative_operator.podAnnotations }}
       {{- end }}
     spec:
+      {{- if .Values.knative_operator.knative_operator.affinity }}
+      affinity:
+      {{- toYaml .Values.knative_operator.knative_operator.affinity | nindent 8 }}
+      {{- end }}
       serviceAccountName: knative-operator
       {{- if and .Values.knative_operator.knative_operator.securityContext }}
       securityContext:

config/charts/knative-operator/values.yaml

@@ -2,6 +2,7 @@ knative_operator:
   knative_operator:
     image: gcr.io/knative-releases/knative.dev/operator/cmd/operator
     tag: {{ tag }}
+    affinity: {}
     containerSecurityContext:
       allowPrivilegeEscalation: false
       readOnlyRootFilesystem: true
@@ -16,6 +17,16 @@ knative_operator:
   operator_webhook:
     image: gcr.io/knative-releases/knative.dev/operator/cmd/webhook
     tag: {{ tag }}
+    affinity:
+      # To avoid node becoming SPOF, spread our replicas to different nodes.
+      podAntiAffinity:
+        preferredDuringSchedulingIgnoredDuringExecution:
+          - podAffinityTerm:
+              labelSelector:
+                matchLabels:
+                  app: operator-webhook
+              topologyKey: kubernetes.io/hostname
+            weight: 100
     containerSecurityContext:
       allowPrivilegeEscalation: false
       readOnlyRootFilesystem: true