Allow configuration of topologySpreadConstraints for flagger deployment

Resolves: #1765
Signed-off-by: Christian Rohmann <[email protected]>

Author: frittentheke

charts/flagger/templates/deployment.yaml

@@ -49,6 +49,10 @@ spec:
       affinity:
         {{- tpl (toYaml .Values.affinity) . | nindent 8 }}
       {{- end }}
+      {{- if .Values.topologySpreadConstraints }}
+      topologySpreadConstraints:
+        {{- tpl (toYaml .Values.topologySpreadConstraints) . | nindent 8 }}
+      {{- end }}
       {{- if .Values.image.pullSecret }}
       imagePullSecrets:
         - name: {{ .Values.image.pullSecret }}
@@ -64,7 +68,7 @@ spec:
         {{- end }}
       {{- if .Values.podPriorityClassName }}
       priorityClassName: {{ .Values.podPriorityClassName }}
-      {{- end }}                  
+      {{- end }}
       containers:
         - name: flagger
           {{- if .Values.securityContext.enabled }}

charts/flagger/values.yaml

@@ -167,6 +167,19 @@ affinity:
               app.kubernetes.io/instance: '{{ .Release.Name }}'
           topologyKey: kubernetes.io/hostname
 
+topologySpreadConstraints:
+  - labelSelector:
+      matchLabels:
+        app.kubernetes.io/name: '{{ template "flagger.name" . }}'
+        app.kubernetes.io/instance: '{{ .Release.Name }}'
+    matchLabelKeys:
+      - pod-template-hash
+    topologyKey: topology.kubernetes.io/zone
+    maxSkew: 1
+    whenUnsatisfiable: ScheduleAnyway
+
+
+
 prometheus:
   # to be used with ingress controllers
   install: false