feat: add topologySpreadConstraints to kops cluster crd

k8s/crds/kops.k8s.io_clusters.yaml

@@ -3748,6 +3748,116 @@ spec:
                     items:
                       type: string
                     type: array
+                  topologySpreadConstraints:
+                    description: |-
+                      You can use topology spread constraints to control how Pods are spread across your cluster 
+                      among failure-domains such as regions, zones, nodes, and other user-defined topology domains.
+                    items:
+                      description: |-
+                        You can define one or multiple topologySpreadConstraints entries to instruct the kube-scheduler 
+                        how to place each incoming Pod in relation to the existing Pods across your cluster.
+                      properties:
+                        maxSkew:
+                          description: |-
+                            maxSkew describes the degree to which Pods may be unevenly distributed. You must specify this field 
+                            and the number must be greater than zero.
+                          type: integer
+                        minDomains:
+                          description: |-
+                            minDomains indicates a minimum number of eligible domains. This field is optional. A domain is a particular 
+                            instance of a topology. An eligible domain is a domain whose nodes match the node selector.
+                          type: integer
+                        topologyKey:
+                          description: |-
+                            topologyKey is the key of node labels. Nodes that have a label with this key and identical values are considered 
+                            to be in the same topology. We call each instance of a topology (in other words, a <key, value> pair) a domain.
+                          type: string
+                        whenUnsatisfiable:
+                          description: |-
+                            whenUnsatisfiable indicates how to deal with a Pod if it doesn't satisfy the spread constraint:
+                            DoNotSchedule (default) tells the scheduler not to schedule it.
+                            ScheduleAnyway tells the scheduler to still schedule it while prioritizing nodes that minimize the skew.
+                          type: string
+                        labelSelector:
+                          description: |-
+                            A label query over a set of resources, in this case pods.
+                            If it's null, this PodAffinityTerm matches with no Pods.
+                          properties:
+                            matchExpressions:
+                              description: matchExpressions is a list
+                                of label selector requirements. The requirements
+                                are ANDed.
+                              items:
+                                description: |-
+                                  A label selector requirement is a selector that contains values, a key, and an operator that
+                                  relates the key and values.
+                                properties:
+                                  key:
+                                    description: key is the label key
+                                      that the selector applies to.
+                                    type: string
+                                  operator:
+                                    description: |-
+                                      operator represents a key's relationship to a set of values.
+                                      Valid operators are In, NotIn, Exists and DoesNotExist.
+                                    type: string
+                                  values:
+                                    description: |-
+                                      values is an array of string values. If the operator is In or NotIn,
+                                      the values array must be non-empty. If the operator is Exists or DoesNotExist,
+                                      the values array must be empty. This array is replaced during a strategic
+                                      merge patch.
+                                    items:
+                                      type: string
+                                    type: array
+                                    x-kubernetes-list-type: atomic
+                                required:
+                                - key
+                                - operator
+                                type: object
+                              type: array
+                              x-kubernetes-list-type: atomic
+                            matchLabels:
+                              additionalProperties:
+                                type: string
+                              description: |-
+                                matchLabels is a map of {key,value} pairs. A single {key,value} in the matchLabels
+                                map is equivalent to an element of matchExpressions, whose key field is "key", the
+                                operator is "In", and the values array contains only "value". The requirements are ANDed.
+                              type: object
+                          type: object
+                          x-kubernetes-map-type: atomic
+                        matchLabelKeys:
+                          description: |-
+                            MatchLabelKeys is a set of pod label keys to select which pods will
+                            be taken into consideration. The keys are used to lookup values from the
+                            incoming pod labels, those key-value labels are merged with `labelSelector` as `key in (value)`
+                            to select the group of existing pods which pods will be taken into consideration
+                            for the incoming pod's pod (anti) affinity. Keys that don't exist in the incoming
+                            pod labels will be ignored. The default value is empty.
+                            The same key is forbidden to exist in both matchLabelKeys and labelSelector.
+                            Also, matchLabelKeys cannot be set when labelSelector isn't set.
+                            This is a beta field and requires enabling MatchLabelKeysInPodAffinity feature gate (enabled by default).
+                          items:
+                            type: string
+                          type: array
+                          x-kubernetes-list-type: atomic
+                        nodeAffinityPolicy:
+                          description: |-
+                            nodeAffinityPolicy indicates how we will treat Pod's nodeAffinity/nodeSelector when calculating pod topology spread skew. Options are:
+                            Honor: only nodes matching nodeAffinity/nodeSelector are included in the calculations.
+                            Ignore: nodeAffinity/nodeSelector are ignored. All nodes are included in the calculations.
+                            If this value is null, the behavior is equivalent to the Honor policy.
+                          type: string
+                        nodeTaintsPolicy:
+                          description: |-
+                            nodeTaintsPolicy indicates how we will treat node taints when calculating pod topology spread skew. Options are:
+                            Honor: nodes without taints, along with tainted nodes for which the incoming pod has a toleration, are included.
+                            Ignore: node taints are ignored. All nodes are included.
+                            If this value is null, the behavior is equivalent to the Ignore policy.
+                          type: string
+                      type: object
+                    type: array
                 type: object
               kubeProxy:
                 description: KubeProxyConfig defines the configuration for a proxy

pkg/apis/kops/cluster.go

@@ -599,6 +599,8 @@ type KubeDNSConfig struct {
 	MemoryLimit *resource.Quantity `json:"memoryLimit,omitempty"`
 	// NodeLocalDNS specifies the configuration for the node-local-dns addon
 	NodeLocalDNS *NodeLocalDNSConfig `json:"nodeLocalDNS,omitempty"`
+	// TopologySpreadConstraints describes how a group of pods ought to spread across topology domains
+	TopologySpreadConstraints []corev1.TopologySpreadConstraint `json:"topologySpreadConstraints,omitempty"`
 }
 
 // NodeLocalDNSConfig are options of the node-local-dns

pkg/apis/kops/v1alpha2/cluster.go

@@ -578,6 +578,8 @@ type KubeDNSConfig struct {
 	MemoryLimit *resource.Quantity `json:"memoryLimit,omitempty"`
 	// NodeLocalDNS specifies the configuration for the node-local-dns addon
 	NodeLocalDNS *NodeLocalDNSConfig `json:"nodeLocalDNS,omitempty"`
+	// TopologySpreadConstraints describes how a group of pods ought to spread across topology domains
+	TopologySpreadConstraints []corev1.TopologySpreadConstraint `json:"topologySpreadConstraints,omitempty"`
 }
 
 // NodeLocalDNSConfig are options of the node-local-dns

pkg/apis/kops/v1alpha3/cluster.go

@@ -564,6 +564,8 @@ type KubeDNSConfig struct {
 	MemoryLimit *resource.Quantity `json:"memoryLimit,omitempty"`
 	// NodeLocalDNS specifies the configuration for the node-local-dns addon
 	NodeLocalDNS *NodeLocalDNSConfig `json:"nodeLocalDNS,omitempty"`
+	// TopologySpreadConstraints describes how a group of pods ought to spread across topology domains
+	TopologySpreadConstraints []corev1.TopologySpreadConstraint `json:"topologySpreadConstraints,omitempty"`
 }
 
 // NodeLocalDNSConfig are options of the node-local-dns