fix(affinity): update affinity on server and aggregator to be automatically set

helm/templates/webhook-deploy.yaml

@@ -103,23 +103,7 @@ spec:
             (.Values.defaults.securityContext | default (dict))
             (.Values.components.webhookServer.securityContext | default (dict))
           ) | nindent 6 }}
-      {{ $podAntiAffinity := dict
-        "podAntiAffinity" (dict
-          "preferredDuringSchedulingIgnoredDuringExecution" (list
-            (dict
-              "weight" 100
-              "podAffinityTerm" (dict
-                "labelSelector" (dict
-                  "matchLabels" (dict "app.kubernetes.io/name" "webhook-server")
-                )
-                "topologyKey" "kubernetes.io/hostname"
-              )
-            )
-          )
-        )
-      }}
-      {{- $userAffinity := deepCopy .Values.insightsController.server.affinity }}
-      {{- include "cloudzero-agent.generateAffinity" (dict "default" .Values.defaults.affinity "affinity" (merge $userAffinity $podAntiAffinity)) | nindent 6 }}
+      {{- include "cloudzero-agent.generateAffinity" (dict "default" .Values.defaults.affinity "affinity" .Values.insightsController.server.affinity) | nindent 6 }}
       {{- include "cloudzero-agent.generateDNSInfo" (dict "defaults" .Values.defaults.dns) | nindent 6 }}
       {{- include "cloudzero-agent.generatePriorityClassName" .Values.defaults.priorityClassName | nindent 6 }}
       {{- include "cloudzero-agent.generateNodeSelector" (dict "default" .Values.defaults.nodeSelector "nodeSelector" .Values.insightsController.server.nodeSelector) | nindent 6 }}

helm/tests/server_aggregator_default_antiaffinity_test.yaml

@@ -0,0 +1,81 @@
+# Regression guard for the default pod anti-affinity now declared directly in
+# values.yaml (server.affinity, aggregator.affinity, and
+# insightsController.server.affinity) rather than hardcoded in the templates.
+#
+# Companion to webhook_antiaffinity_selector_test.yaml, which covers the same
+# behavior for the webhook server. These assert that, with no user overrides,
+# the server and aggregator Deployments render the same soft (preferred),
+# weight-100, same-hostname anti-affinity rule scoped to their own
+# app.kubernetes.io/name label - and that a user can still fully replace the
+# default by overriding affinity.
+suite: test default server/aggregator pod anti-affinity
+templates:
+  - templates/agent-deploy.yaml
+  - templates/aggregator-deploy.yaml
+tests:
+  - it: server should default to a preferred anti-affinity selecting its own pods
+    template: templates/agent-deploy.yaml
+    set:
+      components.agent.mode: clustered
+    asserts:
+      - equal:
+          path: spec.template.spec.affinity.podAntiAffinity.preferredDuringSchedulingIgnoredDuringExecution[0].podAffinityTerm.labelSelector.matchLabels
+          value:
+            app.kubernetes.io/name: server
+      - equal:
+          path: spec.template.spec.affinity.podAntiAffinity.preferredDuringSchedulingIgnoredDuringExecution[0].weight
+          value: 100
+      - equal:
+          path: spec.template.spec.affinity.podAntiAffinity.preferredDuringSchedulingIgnoredDuringExecution[0].podAffinityTerm.topologyKey
+          value: kubernetes.io/hostname
+
+  - it: aggregator should default to a preferred anti-affinity selecting its own pods
+    template: templates/aggregator-deploy.yaml
+    asserts:
+      - equal:
+          path: spec.template.spec.affinity.podAntiAffinity.preferredDuringSchedulingIgnoredDuringExecution[0].podAffinityTerm.labelSelector.matchLabels
+          value:
+            app.kubernetes.io/name: aggregator
+      - equal:
+          path: spec.template.spec.affinity.podAntiAffinity.preferredDuringSchedulingIgnoredDuringExecution[0].weight
+          value: 100
+      - equal:
+          path: spec.template.spec.affinity.podAntiAffinity.preferredDuringSchedulingIgnoredDuringExecution[0].podAffinityTerm.topologyKey
+          value: kubernetes.io/hostname
+
+  - it: users can fully replace the server's default anti-affinity
+    template: templates/agent-deploy.yaml
+    set:
+      components.agent.mode: clustered
+      server.affinity:
+        podAntiAffinity: null
+        nodeAffinity:
+          requiredDuringSchedulingIgnoredDuringExecution:
+            nodeSelectorTerms:
+              - matchExpressions:
+                  - key: srv-only-key
+                    operator: Exists
+    asserts:
+      - notExists:
+          path: spec.template.spec.affinity.podAntiAffinity
+      - equal:
+          path: spec.template.spec.affinity.nodeAffinity.requiredDuringSchedulingIgnoredDuringExecution.nodeSelectorTerms[0].matchExpressions[0].key
+          value: srv-only-key
+
+  - it: users can fully replace the aggregator's default anti-affinity
+    template: templates/aggregator-deploy.yaml
+    set:
+      aggregator.affinity:
+        podAntiAffinity: null
+        nodeAffinity:
+          requiredDuringSchedulingIgnoredDuringExecution:
+            nodeSelectorTerms:
+              - matchExpressions:
+                  - key: agg-only-key
+                    operator: Exists
+    asserts:
+      - notExists:
+          path: spec.template.spec.affinity.podAntiAffinity
+      - equal:
+          path: spec.template.spec.affinity.nodeAffinity.requiredDuringSchedulingIgnoredDuringExecution.nodeSelectorTerms[0].matchExpressions[0].key
+          value: agg-only-key

helm/values.yaml

@@ -1283,11 +1283,25 @@ server:
   # --Limit the size to 8Gi to lower impact on the cluster, and to provide a reasonable backup for the WAL
   emptyDir:
     sizeLimit: 8Gi
-  # Affinity rules
+  # Affinity rules for the server pods.
+  #
+  # Defaults to a preferred (soft) anti-affinity that spreads server pods
+  # across different nodes. Override any of these fields to customize the
+  # behavior, or set podAntiAffinity to null (or affinity to null) to
+  # remove the default entirely. Note: setting affinity to {} will NOT
+  # remove it, since Helm re-merges chart defaults into empty maps.
   #
   # See the Kubernetes documentation for details:
   # https://kubernetes.io/docs/concepts/configuration/assign-pod-node/#affinity-and-anti-affinity
-  affinity: {}
+  affinity:
+    podAntiAffinity:
+      preferredDuringSchedulingIgnoredDuringExecution:
+        - weight: 100
+          podAffinityTerm:
+            labelSelector:
+              matchLabels:
+                app.kubernetes.io/name: server
+            topologyKey: kubernetes.io/hostname
   # Tolerations configuration for the aggregator pods.
   #
   # See the Kubernetes documentation for details:
@@ -1508,9 +1522,24 @@ insightsController:
     tolerations: []
     # Affinity rules for the webhook server pods.
     #
+    # Defaults to a preferred (soft) anti-affinity that spreads webhook
+    # server pods across different nodes. Override any of these fields to
+    # customize the behavior, or set podAntiAffinity to null (or affinity
+    # to null) to remove the default entirely. Note: setting affinity to
+    # {} will NOT remove it, since Helm re-merges chart defaults into
+    # empty maps.
+    #
     # See the Kubernetes documentation for details:
     # https://kubernetes.io/docs/concepts/configuration/assign-pod-node/#affinity-and-anti-affinity
-    affinity: {}
+    affinity:
+      podAntiAffinity:
+        preferredDuringSchedulingIgnoredDuringExecution:
+          - weight: 100
+            podAffinityTerm:
+              labelSelector:
+                matchLabels:
+                  app.kubernetes.io/name: webhook-server
+              topologyKey: kubernetes.io/hostname
     # Annotations to add to the webhook server Deployment.
     deploymentAnnotations: {}
     # Annotations to add to the webhook server pods.
@@ -1806,9 +1835,24 @@ aggregator:
   tolerations: []
   # Affinity rules for the aggregator pods.
   #
+  # Defaults to a preferred (soft) anti-affinity that spreads aggregator
+  # pods across different nodes. Override any of these fields to
+  # customize the behavior, or set podAntiAffinity to null (or affinity
+  # to null) to remove the default entirely. Note: setting affinity to
+  # {} will NOT remove it, since Helm re-merges chart defaults into
+  # empty maps.
+  #
   # See the Kubernetes documentation for details:
   # https://kubernetes.io/docs/concepts/configuration/assign-pod-node/#affinity-and-anti-affinity
-  affinity: {}
+  affinity:
+    podAntiAffinity:
+      preferredDuringSchedulingIgnoredDuringExecution:
+        - weight: 100
+          podAffinityTerm:
+            labelSelector:
+              matchLabels:
+                app.kubernetes.io/name: aggregator
+            topologyKey: kubernetes.io/hostname
 
 # -- Deprecated. Override the name of the chart. Used in resource naming.
 nameOverride: