[addons] Introduce NodeProblemDetector

Node Problem Detector aims to make various node problems visible to
the upstream layers in the cluster management stack. It is a daemon
that runs on each node, detects node problems and reports them to apiserver
so to avoid scheduling new pods on bad nodes and also easily identify
which are the problems on underlying nodes.

Project Home: https://github.com/kubernetes/node-problem-detector

Signed-off-by: dntosas <ntosas@gmail.com>

k8s/crds/kops.k8s.io_clusters.yaml

@@ -3962,6 +3962,35 @@ spec:
                 items:
                   type: string
                 type: array
+              nodeProblemDetector:
+                description: NodeProblemDetector determines the node problem detector
+                  configuration.
+                properties:
+                  cpuRequest:
+                    anyOf:
+                    - type: integer
+                    - type: string
+                    description: 'CPURequest of NodeProblemDetector container. Default:
+                      10m'
+                    pattern: ^(\+|-)?(([0-9]+(\.[0-9]*)?)|(\.[0-9]+))(([KMGTPE]i)|[numkMGTPE]|([eE](\+|-)?(([0-9]+(\.[0-9]*)?)|(\.[0-9]+))))?$
+                    x-kubernetes-int-or-string: true
+                  enabled:
+                    description: 'Enabled enables the NodeProblemDetector. Default:
+                      false'
+                    type: boolean
+                  image:
+                    description: 'Image is the NodeProblemDetector docker container
+                      used Default: k8s.gcr.io/node-problem-detector/node-problem-detector:v0.8.7'
+                    type: string
+                  memoryRequest:
+                    anyOf:
+                    - type: integer
+                    - type: string
+                    description: 'MemoryRequest of NodeProblemDetector container.
+                      Default: 32Mi'
+                    pattern: ^(\+|-)?(([0-9]+(\.[0-9]*)?)|(\.[0-9]+))(([KMGTPE]i)|[numkMGTPE]|([eE](\+|-)?(([0-9]+(\.[0-9]*)?)|(\.[0-9]+))))?$
+                    x-kubernetes-int-or-string: true
+                type: object
               nodeTerminationHandler:
                 description: NodeTerminationHandler determines the cluster autoscaler
                   configuration.

pkg/apis/kops/cluster.go

@@ -161,6 +161,8 @@ type ClusterSpec struct {
 
 	// NodeTerminationHandler determines the node termination handler configuration.
 	NodeTerminationHandler *NodeTerminationHandlerConfig `json:"nodeTerminationHandler,omitempty"`
+	// NodeProblemDetector determines the node problem detector configuration.
+	NodeProblemDetector *NodeProblemDetectorConfig `json:"nodeProblemDetector,omitempty"`
 	// MetricsServer determines the metrics server configuration.
 	MetricsServer *MetricsServerConfig `json:"metricsServer,omitempty"`
 	// CertManager determines the metrics server configuration.

pkg/apis/kops/componentconfig.go

@@ -880,6 +880,23 @@ type NodeTerminationHandlerConfig struct {
 	CPURequest *resource.Quantity `json:"cpuRequest,omitempty"`
 }
 
+// NodeProblemDetector determines the node problem detector configuration.
+type NodeProblemDetectorConfig struct {
+	// Enabled enables the NodeProblemDetector.
+	// Default: false
+	Enabled *bool `json:"enabled,omitempty"`
+	// Image is the NodeProblemDetector docker container used
+	// Default: k8s.gcr.io/node-problem-detector/node-problem-detector:v0.8.7
+	Image string `json:"image,omitempty"`
+
+	// MemoryRequest of NodeProblemDetector container.
+	// Default: 32Mi
+	MemoryRequest *resource.Quantity `json:"memoryRequest,omitempty"`
+	// CPURequest of NodeProblemDetector container.
+	// Default: 10m
+	CPURequest *resource.Quantity `json:"cpuRequest,omitempty"`
+}
+
 // ClusterAutoscalerConfig determines the cluster autoscaler configuration.
 type ClusterAutoscalerConfig struct {
 	// Enabled enables the cluster autoscaler.

pkg/apis/kops/v1alpha2/cluster.go

@@ -160,6 +160,8 @@ type ClusterSpec struct {
 
 	// NodeTerminationHandler determines the cluster autoscaler configuration.
 	NodeTerminationHandler *NodeTerminationHandlerConfig `json:"nodeTerminationHandler,omitempty"`
+	// NodeProblemDetector determines the node problem detector configuration.
+	NodeProblemDetector *NodeProblemDetectorConfig `json:"nodeProblemDetector,omitempty"`
 	// MetricsServer determines the metrics server configuration.
 	MetricsServer *MetricsServerConfig `json:"metricsServer,omitempty"`
 	// CertManager determines the metrics server configuration.

pkg/apis/kops/v1alpha2/componentconfig.go

@@ -879,6 +879,23 @@ type NodeTerminationHandlerConfig struct {
 	CPURequest *resource.Quantity `json:"cpuRequest,omitempty"`
 }
 
+// NodeProblemDetector determines the node problem detector configuration.
+type NodeProblemDetectorConfig struct {
+	// Enabled enables the NodeProblemDetector.
+	// Default: false
+	Enabled *bool `json:"enabled,omitempty"`
+	// Image is the NodeProblemDetector docker container used
+	// Default: k8s.gcr.io/node-problem-detector/node-problem-detector:v0.8.7
+	Image string `json:"image,omitempty"`
+
+	// MemoryRequest of NodeProblemDetector container.
+	// Default: 32Mi
+	MemoryRequest *resource.Quantity `json:"memoryRequest,omitempty"`
+	// CPURequest of NodeProblemDetector container.
+	// Default: 10m
+	CPURequest *resource.Quantity `json:"cpuRequest,omitempty"`
+}
+
 // ClusterAutoscalerConfig determines the cluster autoscaler configuration.
 type ClusterAutoscalerConfig struct {
 	// Enabled enables the cluster autoscaler.

pkg/model/components/nodeproblemdetector.go

@@ -0,0 +1,63 @@
+/*
+Copyright 2021 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package components
+
+import (
+	"k8s.io/apimachinery/pkg/api/resource"
+	"k8s.io/kops/pkg/apis/kops"
+	"k8s.io/kops/upup/pkg/fi"
+	"k8s.io/kops/upup/pkg/fi/loader"
+)
+
+// NodeProblemDetectorOptionsBuilder adds options for the node problem detector to the model.
+type NodeProblemDetectorOptionsBuilder struct {
+	*OptionsContext
+}
+
+var _ loader.OptionsBuilder = &NodeProblemDetectorOptionsBuilder{}
+
+func (b *NodeProblemDetectorOptionsBuilder) BuildOptions(o interface{}) error {
+	clusterSpec := o.(*kops.ClusterSpec)
+	if clusterSpec.NodeProblemDetector == nil {
+		return nil
+	}
+	npd := clusterSpec.NodeProblemDetector
+
+	if npd.Enabled == nil {
+		npd.Enabled = fi.Bool(false)
+	}
+
+	if npd.CPURequest == nil {
+		defaultCPURequest := resource.MustParse("10m")
+		npd.CPURequest = &defaultCPURequest
+	}
+
+	if npd.MemoryRequest == nil {
+		defaultMemoryRequest := resource.MustParse("32Mi")
+		npd.MemoryRequest = &defaultMemoryRequest
+	}
+
+	if npd.Enabled == nil {
+		npd.Enabled = fi.Bool(false)
+	}
+
+	if npd.Image == "" {
+		npd.Image = "k8s.gcr.io/node-problem-detector/node-problem-detector:v0.8.7"
+	}
+
+	return nil
+}