[v18] [buddy] teleport-kube-agent: Add topologySpreadConstraints

docs/pages/includes/helm-reference/zz_generated.teleport-kube-agent.mdx

@@ -1421,6 +1421,42 @@ more details on possible values for `extra_fields`.
 See [the Kubernetes documentation](https://kubernetes.io/docs/concepts/configuration/assign-pod-node/#affinity-and-anti-affinity)
 for more details.
 
+## `disableTopologySpreadConstraints`
+
+| Type | Default |
+|------|---------|
+| `bool` | `false` |
+
+`disableTopologySpreadConstraints` turns off the topology spread constraints.
+The feature is automatically turned off on Kubernetes versions below 1.18.
+
+## `topologySpreadConstraints`
+
+| Type | Default |
+|------|---------|
+| `list` | `[]` |
+
+`topologySpreadConstraints` sets the topology spread constraints for any pods created by the chart.
+See [the Kubernetes documentation](https://kubernetes.io/docs/concepts/scheduling-eviction/topology-spread-constraints/)
+for more details.
+
+When unset, the chart defaults to a soft topology spread constraint
+that tries to spread pods across hosts and zones.
+
+```
+topologySpreadConstraints:
+  - maxSkew: 1
+    topologyKey: kubernetes.io/hostname
+    whenUnsatisfiable: ScheduleAnyway
+    labelSelector:
+      matchLabels: # dynamically computed
+  - maxSkew: 1
+    topologyKey: topology.kubernetes.io/zone
+    whenUnsatisfiable: ScheduleAnyway
+    labelSelector:
+      matchLabels: # dynamically computed
+```
+
 ## `dnsConfig`
 
 | Type | Default |

examples/chart/teleport-kube-agent/.lint/topology-spread-constraints.yaml

@@ -0,0 +1,13 @@
+authToken: auth-token
+proxyAddr: proxy.example.com:3080
+roles: kube
+kubeClusterName: test-kube-cluster
+topologySpreadConstraints:
+  - maxSkew: 1
+    topologyKey: kubernetes.io/hostname
+    whenUnsatisfiable: DoNotSchedule
+    labelSelector:
+      matchLabels:
+        app: foo
+    matchLabelKeys:
+      - pod-template-hash

examples/chart/teleport-kube-agent/templates/deployment.yaml

@@ -81,6 +81,9 @@ spec:
         {{- end }}
         {{- end }}
       {{- end }}
+      {{- if .Values.topologySpreadConstraints }}
+      topologySpreadConstraints: {{- toYaml .Values.topologySpreadConstraints | nindent 8 }}
+      {{- end }}
       {{- if .Values.tolerations }}
       tolerations:
         {{- toYaml .Values.tolerations | nindent 6 }}

examples/chart/teleport-kube-agent/templates/statefulset.yaml

@@ -2,6 +2,7 @@
 # Warning to maintainers, any changes to this file that are not specific to the StatefulSet need to also be duplicated
 # in the deployment.yaml file.
 #
+{{- $topologySpreadConstraints := and (semverCompare ">=1.18.0-0" .Capabilities.KubeVersion.Version) (not .Values.disableTopologySpreadConstraints) }}
 {{- $replicaCount := (coalesce .Values.replicaCount .Values.highAvailability.replicaCount "1") }}
 apiVersion: apps/v1
 kind: StatefulSet
@@ -84,6 +85,25 @@ spec:
         {{- end }}
         {{- end }}
       {{- end }}
+{{- if $topologySpreadConstraints }}
+  {{- if .Values.topologySpreadConstraints }}
+      topologySpreadConstraints: {{- toYaml .Values.topologySpreadConstraints | nindent 8 }}
+  {{- else }}
+      topologySpreadConstraints:
+        - maxSkew: 1
+          topologyKey: kubernetes.io/hostname
+          whenUnsatisfiable: ScheduleAnyway
+          labelSelector:
+            matchLabels:
+              app: {{ .Release.Name }}
+        - maxSkew: 1
+          topologyKey: topology.kubernetes.io/zone
+          whenUnsatisfiable: ScheduleAnyway
+          labelSelector:
+            matchLabels:
+              app: {{ .Release.Name }}
+  {{- end }}
+{{- end }}
       {{- if .Values.tolerations }}
       tolerations:
         {{- toYaml .Values.tolerations | nindent 6 }}