clitools/pkg/node/agent.go
raw ยท 10036 bytes
package node
import (
"context"
"fmt"
"reflect"
"strings"
appsv1 "k8s.io/api/apps/v1"
corev1 "k8s.io/api/core/v1"
rbacv1 "k8s.io/api/rbac/v1"
apierrors "k8s.io/apimachinery/pkg/api/errors"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/client-go/kubernetes"
"k8s.io/klog/v2"
monov1alpha1 "example.com/monok8s/pkg/apis/monok8s/v1alpha1"
"example.com/monok8s/pkg/kube"
templates "example.com/monok8s/pkg/templates"
)
const (
controlAgentName = "control-agent"
controlAgentNodeSelectorValue = "true"
controlAgentImage = "localhost/monok8s/control-agent:dev"
kubeconfig = "/etc/kubernetes/admin.conf"
)
func ApplyControlAgentDaemonSetResources(ctx context.Context, n *NodeContext) error {
// Only the control-plane should bootstrap this DaemonSet definition.
// And only when the feature is enabled.
if strings.TrimSpace(n.Config.Spec.ClusterRole) != "control-plane" || !n.Config.Spec.EnableControlAgent {
klog.InfoS("skipped for", "clusterRole", n.Config.Spec.ClusterRole, "enableControlAgent", n.Config.Spec.EnableControlAgent)
return nil
}
err := ApplyCRDs(ctx, n)
if err != nil {
return err
}
namespace := strings.TrimSpace(n.Config.Namespace)
if namespace == "" {
namespace = templates.DefaultNamespace
}
clients, err := kube.NewClientsFromKubeconfig(kubeconfig)
if err != nil {
return fmt.Errorf("build kube clients from %s: %w", kubeconfig, err)
}
labels := map[string]string{
"app.kubernetes.io/name": controlAgentName,
"app.kubernetes.io/component": "agent",
"app.kubernetes.io/part-of": "monok8s",
"app.kubernetes.io/managed-by": "ctl",
}
kubeClient := clients.Kubernetes
if err := applyControlAgentServiceAccount(ctx, kubeClient, namespace, labels); err != nil {
return fmt.Errorf("apply serviceaccount: %w", err)
}
if err := applyControlAgentClusterRole(ctx, kubeClient, labels); err != nil {
return fmt.Errorf("apply clusterrole: %w", err)
}
if err := applyControlAgentClusterRoleBinding(ctx, kubeClient, namespace, labels); err != nil {
return fmt.Errorf("apply clusterrolebinding: %w", err)
}
if err := applyControlAgentDaemonSet(ctx, kubeClient, namespace, labels); err != nil {
return fmt.Errorf("apply daemonset: %w", err)
}
return nil
}
func applyControlAgentServiceAccount(ctx context.Context, kubeClient kubernetes.Interface, namespace string, labels map[string]string) error {
want := &corev1.ServiceAccount{
ObjectMeta: metav1.ObjectMeta{
Name: controlAgentName,
Namespace: namespace,
Labels: labels,
},
}
existing, err := kubeClient.CoreV1().ServiceAccounts(namespace).Get(ctx, controlAgentName, metav1.GetOptions{})
if apierrors.IsNotFound(err) {
_, err = kubeClient.CoreV1().ServiceAccounts(namespace).Create(ctx, want, metav1.CreateOptions{})
return err
}
if err != nil {
return err
}
changed := false
if !reflect.DeepEqual(existing.Labels, want.Labels) {
existing.Labels = want.Labels
changed = true
}
if !changed {
return nil
}
_, err = kubeClient.CoreV1().ServiceAccounts(namespace).Update(ctx, existing, metav1.UpdateOptions{})
return err
}
func applyControlAgentClusterRole(ctx context.Context, kubeClient kubernetes.Interface, labels map[string]string) error {
wantRules := []rbacv1.PolicyRule{
{
APIGroups: []string{monov1alpha1.Group},
Resources: []string{"osupgrades"},
Verbs: []string{"get", "list", "watch"},
},
{
APIGroups: []string{monov1alpha1.Group},
Resources: []string{"osupgrades/status"},
Verbs: []string{"get", "patch", "update"},
},
{
APIGroups: []string{""},
Resources: []string{"nodes"},
Verbs: []string{"get", "list", "watch"},
},
}
want := &rbacv1.ClusterRole{
ObjectMeta: metav1.ObjectMeta{
Name: controlAgentName,
Labels: labels,
},
Rules: wantRules,
}
existing, err := kubeClient.RbacV1().ClusterRoles().Get(ctx, controlAgentName, metav1.GetOptions{})
if apierrors.IsNotFound(err) {
_, err = kubeClient.RbacV1().ClusterRoles().Create(ctx, want, metav1.CreateOptions{})
return err
}
if err != nil {
return err
}
changed := false
if !reflect.DeepEqual(existing.Labels, want.Labels) {
existing.Labels = want.Labels
changed = true
}
if !reflect.DeepEqual(existing.Rules, want.Rules) {
existing.Rules = want.Rules
changed = true
}
if !changed {
return nil
}
_, err = kubeClient.RbacV1().ClusterRoles().Update(ctx, existing, metav1.UpdateOptions{})
return err
}
func applyControlAgentClusterRoleBinding(ctx context.Context, kubeClient kubernetes.Interface, namespace string, labels map[string]string) error {
wantRoleRef := rbacv1.RoleRef{
APIGroup: rbacv1.GroupName,
Kind: "ClusterRole",
Name: controlAgentName,
}
wantSubjects := []rbacv1.Subject{
{
Kind: "ServiceAccount",
Name: controlAgentName,
Namespace: namespace,
},
}
want := &rbacv1.ClusterRoleBinding{
ObjectMeta: metav1.ObjectMeta{
Name: controlAgentName,
Labels: labels,
},
RoleRef: wantRoleRef,
Subjects: wantSubjects,
}
existing, err := kubeClient.RbacV1().ClusterRoleBindings().Get(ctx, controlAgentName, metav1.GetOptions{})
if apierrors.IsNotFound(err) {
_, err = kubeClient.RbacV1().ClusterRoleBindings().Create(ctx, want, metav1.CreateOptions{})
return err
}
if err != nil {
return err
}
// roleRef is immutable. If it differs, fail loudly instead of pretending we can patch it.
if !reflect.DeepEqual(existing.RoleRef, want.RoleRef) {
return fmt.Errorf("existing ClusterRoleBinding %q has different roleRef and must be recreated", controlAgentName)
}
changed := false
if !reflect.DeepEqual(existing.Labels, want.Labels) {
existing.Labels = want.Labels
changed = true
}
if !reflect.DeepEqual(existing.Subjects, want.Subjects) {
existing.Subjects = want.Subjects
changed = true
}
if !changed {
return nil
}
_, err = kubeClient.RbacV1().ClusterRoleBindings().Update(ctx, existing, metav1.UpdateOptions{})
return err
}
func applyControlAgentDaemonSet(ctx context.Context, kubeClient kubernetes.Interface, namespace string, labels map[string]string) error {
privileged := true
dsLabels := map[string]string{
"app.kubernetes.io/name": controlAgentName,
"app.kubernetes.io/component": "agent",
"app.kubernetes.io/part-of": "monok8s",
"app.kubernetes.io/managed-by": "ctl",
}
want := &appsv1.DaemonSet{
ObjectMeta: metav1.ObjectMeta{
Name: controlAgentName,
Namespace: namespace,
Labels: labels,
},
Spec: appsv1.DaemonSetSpec{
Selector: &metav1.LabelSelector{
MatchLabels: map[string]string{
"app.kubernetes.io/name": controlAgentName,
},
},
Template: corev1.PodTemplateSpec{
ObjectMeta: metav1.ObjectMeta{
Labels: dsLabels,
},
Spec: corev1.PodSpec{
ServiceAccountName: controlAgentName,
HostNetwork: true,
HostPID: true,
DNSPolicy: corev1.DNSClusterFirstWithHostNet,
NodeSelector: map[string]string{
monov1alpha1.ControlAgentKey: controlAgentNodeSelectorValue,
},
Tolerations: []corev1.Toleration{
{Operator: corev1.TolerationOpExists},
},
Containers: []corev1.Container{
{
Name: "agent",
Image: controlAgentImage,
ImagePullPolicy: corev1.PullNever,
Args: []string{"agent", "--env-file", "$(CLUSTER_ENV_FILE)"},
Env: []corev1.EnvVar{
{
Name: "NODE_NAME",
ValueFrom: &corev1.EnvVarSource{
FieldRef: &corev1.ObjectFieldSelector{
APIVersion: "v1",
FieldPath: "spec.nodeName",
},
},
},
{
Name: "CLUSTER_ENV_FILE",
Value: "/host/opt/monok8s/config/cluster.env",
},
{
Name: "FW_ENV_CONFIG_FILE",
Value: "/host/etc/fw_env.config",
},
},
SecurityContext: &corev1.SecurityContext{
Privileged: &privileged,
},
VolumeMounts: []corev1.VolumeMount{
{
Name: "host-dev",
MountPath: "/dev",
},
{
Name: "host-etc",
MountPath: "/host/etc",
ReadOnly: true,
},
{
Name: "host-config",
MountPath: "/host/opt/monok8s/config",
ReadOnly: true,
},
},
},
},
Volumes: []corev1.Volume{
{
Name: "host-dev",
VolumeSource: corev1.VolumeSource{
HostPath: &corev1.HostPathVolumeSource{
Path: "/dev",
Type: hostPathType(corev1.HostPathDirectory),
},
},
},
{
Name: "host-etc",
VolumeSource: corev1.VolumeSource{
HostPath: &corev1.HostPathVolumeSource{
Path: "/etc",
Type: hostPathType(corev1.HostPathDirectory),
},
},
},
{
Name: "host-config",
VolumeSource: corev1.VolumeSource{
HostPath: &corev1.HostPathVolumeSource{
Path: "/opt/monok8s/config",
Type: hostPathType(corev1.HostPathDirectory),
},
},
},
},
},
},
},
}
existing, err := kubeClient.AppsV1().DaemonSets(namespace).Get(ctx, controlAgentName, metav1.GetOptions{})
if apierrors.IsNotFound(err) {
_, err = kubeClient.AppsV1().DaemonSets(namespace).Create(ctx, want, metav1.CreateOptions{})
return err
}
if err != nil {
return err
}
changed := false
if !reflect.DeepEqual(existing.Labels, want.Labels) {
existing.Labels = want.Labels
changed = true
}
if !reflect.DeepEqual(existing.Spec, want.Spec) {
existing.Spec = want.Spec
changed = true
}
if !changed {
return nil
}
_, err = kubeClient.AppsV1().DaemonSets(namespace).Update(ctx, existing, metav1.UpdateOptions{})
return err
}
func hostPathType(t corev1.HostPathType) *corev1.HostPathType {
return &t
}
func mountPropagationMode(m corev1.MountPropagationMode) *corev1.MountPropagationMode {
return &m
}