[stable/rocketchat] Add Affinity, podAntiAffinity, Add PodDisruptionBudget (#14138)

Signed-off-by: Stefan Andres <s.andres@syseleven.de>

stable/rocketchat/Chart.yaml

@@ -1,6 +1,6 @@
 apiVersion: v1
 name: rocketchat
-version: 1.1.2
+version: 1.1.3
 appVersion: 1.0.3
 description: Prepare to take off with the ultimate chat platform, experience the next level of team communications
 keywords:

stable/rocketchat/README.md

@@ -53,6 +53,10 @@ Parameter | Description | Default
 `smtp.host` | Hostname of the SMTP server | `""`
 `smtp.port` | Port of the SMTP server | `587`
 `extraEnv` | Extra environment variables for Rocket.Chat. Used with `tpl` function, so this needs to be a string | `""`
+`podAntiAffinity` | Pod anti-affinity can prevent the scheduler from placing RocketChat replicas on the same node. The default value "soft" means that the scheduler should *prefer* to not schedule two replica pods onto the same node but no guarantee is provided. The value "hard" means that the scheduler is *required* to not schedule two replica pods onto the same node. The value "" will disable pod anti-affinity so that no anti-affinity rules will be configured. | `""` |
+`podAntiAffinityTopologyKey` | If anti-affinity is enabled sets the topologyKey to use for anti-affinity. This can be changed to, for example `failure-domain.beta.kubernetes.io/zone`| `kubernetes.io/hostname` |
+| `affinity` | Assign custom affinity rules to the RocketChat instance https://kubernetes.io/docs/concepts/configuration/assign-pod-node/ | `{}` |
+`minAvailable` | Minimum number / percentage of pods that should remain scheduled | `1` |
 `externalMongodbUrl` | MongoDB URL if using an externally provisioned MongoDB | `""`
 `externalMongodbOplogUrl` | MongoDB OpLog URL if using an externally provisioned MongoDB. Required if `externalMongodbUrl` is set | `""`
 `mongodb.enabled` | Enable or disable MongoDB dependency. Refer to the [stable/mongodb docs](https://github.com/helm/charts/tree/master/stable/mongodb#configuration) for more information | `true`

stable/rocketchat/templates/deployment.yaml

@@ -89,3 +89,27 @@ spec:
       {{- else }}
         emptyDir: {}
       {{- end }}
+{{- if or .Values.podAntiAffinity .Values.affinity }}
+      affinity:
+{{- if .Values.affinity }}
+{{ toYaml .Values.affinity | indent 4 }}
+{{- end }}
+{{- if eq .Values.podAntiAffinity "hard" }}
+        podAntiAffinity:
+          requiredDuringSchedulingIgnoredDuringExecution:
+          - topologyKey: {{ .Values.podAntiAffinityTopologyKey }}
+            labelSelector:
+              matchLabels:
+                app.kubernetes.io/name: {{ include "rocketchat.name" . }}
+{{- else if eq .Values.podAntiAffinity "soft" }}
+        podAntiAffinity:
+          preferredDuringSchedulingIgnoredDuringExecution:
+          - weight: 100
+            podAffinityTerm:
+              topologyKey: {{ .Values.podAntiAffinityTopologyKey }}
+              labelSelector:
+                matchLabels:
+                  app.kubernetes.io/name: {{ include "rocketchat.name" . }}
+                  app.kubernetes.io/instance: {{ .Release.Name }}
+{{- end }}
+{{- end }}

stable/rocketchat/templates/poddisruptionbudget.yaml

@@ -0,0 +1,17 @@
+{{- if gt .Values.replicaCount 1.0 }}
+apiVersion: policy/v1beta1
+kind: PodDisruptionBudget
+metadata:
+  labels:
+    app.kubernetes.io/name: {{ include "rocketchat.name" . }}
+    helm.sh/chart: {{ .Chart.Name }}-{{ .Chart.Version }}
+    app.kubernetes.io/instance: {{ .Release.Name }}
+    app.kubernetes.io/managed-by: {{ .Release.Service }}
+  name: {{ template "rocketchat.fullname" . }}
+spec:
+  selector:
+    matchLabels:
+      app.kubernetes.io/name: {{ include "rocketchat.name" . }}
+      app.kubernetes.io/instance: {{ .Release.Name }}
+  minAvailable: {{ .Values.minAvailable }}
+{{- end }}

stable/rocketchat/values.yaml

@@ -11,6 +11,7 @@ image:
 # host:
 
 replicaCount: 1
+minAvailable: 1
 
 smtp:
   enabled: false
@@ -26,6 +27,32 @@ extraEnv:  # |
   # - name: MONGO_OPLOG_URL
   #   value: mongodb://oploguser:password@rocket-1:27017/local&replicaSet=rs0
 
+## Pod anti-affinity can prevent the scheduler from placing RocketChat replicas on the same node.
+## The default value "soft" means that the scheduler should *prefer* to not schedule two replica pods onto the same node but no guarantee is provided.
+## The value "hard" means that the scheduler is *required* to not schedule two replica pods onto the same node.
+## The value "" will disable pod anti-affinity so that no anti-affinity rules will be configured.
+##
+podAntiAffinity: ""
+
+## If anti-affinity is enabled sets the topologyKey to use for anti-affinity.
+## This can be changed to, for example, failure-domain.beta.kubernetes.io/zone
+##
+podAntiAffinityTopologyKey: kubernetes.io/hostname
+
+## Assign custom affinity rules to the RocketChat instance
+## ref: https://kubernetes.io/docs/concepts/configuration/assign-pod-node/
+##
+affinity: {}
+# nodeAffinity:
+#   requiredDuringSchedulingIgnoredDuringExecution:
+#     nodeSelectorTerms:
+#     - matchExpressions:
+#       - key: kubernetes.io/e2e-az-name
+#         operator: In
+#         values:
+#         - e2e-az1
+#         - e2e-az2
+
 ## MongoDB URL if using an externally provisioned MongoDB
 externalMongodbUrl:  # mongodb://user:password@localhost:27017/rocketchat
 externalMongodbOplogUrl:  # mongodb://user:password@localhost:27017/local?replicaSet=rs0&authSource=admin