[feat] Helm: add support for topologySpreadConstraints

CHANGELOG.md

@@ -57,6 +57,7 @@ request adding CHANGELOG notes for breaking (!) changes and possibly other secti
 - Added `--no-sts` flag to CLI to support S3-compatible storage systems that do not have Security Token Service available.
 - Support credential vending for federated catalogs. `ALLOW_FEDERATED_CATALOGS_CREDENTIAL_VENDING` (default: true) was added to toggle this feature.
 - Enhanced catalog federation with SigV4 authentication support, additional authentication types for credential vending, and location-based access restrictions to block credential vending for remote tables outside allowed location lists.
+- Added `topologySpreadConstraints` support in Helm chart.
 
 ### Changes
 

helm/polaris/README.md

@@ -437,6 +437,7 @@ ct install --namespace polaris --charts ./helm/polaris
 | tasks.maxConcurrentTasks | string | `nil` | The maximum number of concurrent tasks that can be executed at the same time. The default is the number of available cores. |
 | tasks.maxQueuedTasks | string | `nil` | The maximum number of tasks that can be queued up for execution. The default is Integer.MAX_VALUE. |
 | tolerations | list | `[]` | A list of tolerations to apply to polaris pods. See https://kubernetes.io/docs/concepts/scheduling-eviction/taint-and-toleration/. |
+| topologySpreadConstraints | list | `[]` | Topology spread constraints for polaris pods. See https://kubernetes.io/docs/concepts/scheduling-eviction/topology-spread-constraints/#topologyspreadconstraints-field. |
 | tracing.attributes | object | `{}` | Resource attributes to identify the polaris service among other tracing sources. See https://opentelemetry.io/docs/reference/specification/resource/semantic_conventions/#service. If left empty, traces will be attached to a service named "Apache Polaris"; to change this, provide a service.name attribute here. |
 | tracing.enabled | bool | `false` | Specifies whether tracing for the polaris server should be enabled. |
 | tracing.endpoint | string | `"http://otlp-collector:4317"` | The collector endpoint URL to connect to (required). The endpoint URL must have either the http:// or the https:// scheme. The collector must talk the OpenTelemetry protocol (OTLP) and the port must be its gRPC port (by default 4317). See https://quarkus.io/guides/opentelemetry for more information. |

helm/polaris/templates/deployment.yaml

@@ -139,6 +139,17 @@ spec:
         {{- if .Values.extraVolumes }}
         {{- tpl (toYaml .Values.extraVolumes) . | nindent 8 }}
         {{- end }}
+      {{- if .Values.topologySpreadConstraints }}
+      topologySpreadConstraints:
+      {{- range .Values.topologySpreadConstraints }}
+        - maxSkew: {{ .maxSkew }}
+          topologyKey: {{ .topologyKey }}
+          whenUnsatisfiable: {{ .whenUnsatisfiable }}
+          labelSelector:
+            matchLabels:
+              {{- include "polaris.selectorLabels" $ | nindent 14 }}
+      {{- end }}
+      {{- end }}
       {{- if .Values.nodeSelector }}
       nodeSelector:
         {{- tpl (toYaml .Values.nodeSelector) . | nindent 8 }}

helm/polaris/tests/deployment_test.yaml

@@ -1303,3 +1303,28 @@ tests:
               secretKeyRef:
                 name: polaris-oidc-secret
                 key: client-secret
+
+  - it: should not set topologySpreadConstraints by default
+    template: deployment.yaml
+    asserts:
+      - notExists:
+          path: spec.template.spec.topologySpreadConstraints
+
+  - it: should set topologySpreadConstraints and inject label selector
+    template: deployment.yaml
+    set:
+      topologySpreadConstraints:
+        - maxSkew: 1
+          topologyKey: "kubernetes.io/hostname"
+          whenUnsatisfiable: DoNotSchedule
+    asserts:
+      - equal:
+          path: spec.template.spec.topologySpreadConstraints
+          value:
+            - maxSkew: 1
+              topologyKey: "kubernetes.io/hostname"
+              whenUnsatisfiable: DoNotSchedule
+              labelSelector:
+                matchLabels:
+                  app.kubernetes.io/name: polaris
+                  app.kubernetes.io/instance: polaris-release

helm/polaris/values.yaml

@@ -294,6 +294,12 @@ affinity: {}
 #                values:
 #                  - polaris
 
+# -- Topology spread constraints for polaris pods. See https://kubernetes.io/docs/concepts/scheduling-eviction/topology-spread-constraints/#topologyspreadconstraints-field.
+topologySpreadConstraints: []
+  # - maxSkew: 1
+  #   topologyKey: topology.kubernetes.io/zone
+  #   whenUnsatisfiable: DoNotSchedule
+
 # -- Configures the liveness probe for polaris pods.
 livenessProbe:
   # -- Number of seconds after the container has started before liveness probes are initiated. Minimum value is 0.

site/content/in-dev/unreleased/helm.md

@@ -442,6 +442,7 @@ ct install --namespace polaris --charts ./helm/polaris
 | tasks.maxConcurrentTasks | string | `nil` | The maximum number of concurrent tasks that can be executed at the same time. The default is the number of available cores. |
 | tasks.maxQueuedTasks | string | `nil` | The maximum number of tasks that can be queued up for execution. The default is Integer.MAX_VALUE. |
 | tolerations | list | `[]` | A list of tolerations to apply to polaris pods. See https://kubernetes.io/docs/concepts/scheduling-eviction/taint-and-toleration/. |
+| topologySpreadConstraints | list | `[]` | Topology spread constraints for polaris pods. See https://kubernetes.io/docs/concepts/scheduling-eviction/topology-spread-constraints/#topologyspreadconstraints-field. |
 | tracing.attributes | object | `{}` | Resource attributes to identify the polaris service among other tracing sources. See https://opentelemetry.io/docs/reference/specification/resource/semantic_conventions/#service. If left empty, traces will be attached to a service named "Apache Polaris"; to change this, provide a service.name attribute here. |
 | tracing.enabled | bool | `false` | Specifies whether tracing for the polaris server should be enabled. |
 | tracing.endpoint | string | `"http://otlp-collector:4317"` | The collector endpoint URL to connect to (required). The endpoint URL must have either the http:// or the https:// scheme. The collector must talk the OpenTelemetry protocol (OTLP) and the port must be its gRPC port (by default 4317). See https://quarkus.io/guides/opentelemetry for more information. |