feat(helm): allow customizing chart deployment strategy (#1190)

This pull request introduces support for customizing the deployment
strategy in the Helm chart.
The main enhancement allows users to specify deployment strategies,
such as `Replace`, allowing an existing Pod to be destroyed before the
new one is allocated.

* Added support for specifying a custom deployment `strategy` in the
  `deployment.yaml` template, which will use the values provided in
  `.Values.strategy`.

Fixes
#1189

---------

Co-authored-by: Lukas Metzner <lukas.metzner@hetzner-cloud.de>

Author: siryur

chart/templates/deployment.yaml

@@ -5,6 +5,10 @@ metadata:
   name: {{ include "hcloud-cloud-controller-manager.name" . }}
   namespace: {{ .Release.Namespace }}
 spec:
+  {{- with .Values.strategy }}
+  strategy:
+    {{- toYaml . | nindent 4 }}
+  {{- end }}
   replicas: {{ .Values.replicaCount }}
   revisionHistoryLimit: 2
   selector:

chart/values.yaml

@@ -124,6 +124,14 @@ selectorLabels:
   app.kubernetes.io/name: '{{ include "hcloud-cloud-controller-manager.name" $ }}'
   app.kubernetes.io/instance: "{{ $.Release.Name }}"
 
+# Deployment strategy for the hccm Pod.
+# See https://kubernetes.io/docs/concepts/workloads/controllers/deployment/#strategy
+strategy: {}
+#   type: RollingUpdate
+#   rollingUpdate:
+#     maxSurge: 1
+#     maxUnavailable: 1
+
 additionalTolerations: []
 
 # nodeSelector: