cli: declare mastersecret as immutable and print attestationCfg diff in warning (#2167)

cli/internal/kubernetes/kubernetes.go

@@ -10,3 +10,72 @@ Package kubernetes provides functions to interact with a live cluster to the CLI
 Currently it is used to implement the status and upgrade commands.
 */
 package kubernetes
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/edgelesssys/constellation/v2/internal/constants"
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/tools/clientcmd"
+)
+
+func newClient(kubeconfigPath string) (kubernetes.Interface, error) {
+	kubeConfig, err := clientcmd.BuildConfigFromFlags("", kubeconfigPath)
+	if err != nil {
+		return nil, fmt.Errorf("building kubernetes config: %w", err)
+	}
+
+	kubeClient, err := kubernetes.NewForConfig(kubeConfig)
+	if err != nil {
+		return nil, fmt.Errorf("setting up kubernetes client: %w", err)
+	}
+	return kubeClient, nil
+}
+
+// StableInterface is an interface to interact with stable resources.
+type StableInterface interface {
+	GetCurrentConfigMap(ctx context.Context, name string) (*corev1.ConfigMap, error)
+	UpdateConfigMap(ctx context.Context, configMap *corev1.ConfigMap) (*corev1.ConfigMap, error)
+	CreateConfigMap(ctx context.Context, configMap *corev1.ConfigMap) (*corev1.ConfigMap, error)
+	KubernetesVersion() (string, error)
+}
+
+// NewStableClient returns a new StableClient.
+func NewStableClient(kubeconfigPath string) (StableInterface, error) {
+	client, err := newClient(kubeconfigPath)
+	if err != nil {
+		return nil, err
+	}
+	return &stableClient{client}, nil
+}
+
+type stableClient struct {
+	client kubernetes.Interface
+}
+
+// GetCurrentConfigMap returns a ConfigMap given it's name.
+func (u *stableClient) GetCurrentConfigMap(ctx context.Context, name string) (*corev1.ConfigMap, error) {
+	return u.client.CoreV1().ConfigMaps(constants.ConstellationNamespace).Get(ctx, name, metav1.GetOptions{})
+}
+
+// UpdateConfigMap updates the given ConfigMap.
+func (u *stableClient) UpdateConfigMap(ctx context.Context, configMap *corev1.ConfigMap) (*corev1.ConfigMap, error) {
+	return u.client.CoreV1().ConfigMaps(constants.ConstellationNamespace).Update(ctx, configMap, metav1.UpdateOptions{})
+}
+
+// CreateConfigMap creates the given ConfigMap.
+func (u *stableClient) CreateConfigMap(ctx context.Context, configMap *corev1.ConfigMap) (*corev1.ConfigMap, error) {
+	return u.client.CoreV1().ConfigMaps(constants.ConstellationNamespace).Create(ctx, configMap, metav1.CreateOptions{})
+}
+
+// KubernetesVersion returns the Kubernetes version of the cluster.
+func (u *stableClient) KubernetesVersion() (string, error) {
+	serverVersion, err := u.client.Discovery().ServerVersion()
+	if err != nil {
+		return "", err
+	}
+	return serverVersion.GitVersion, nil
+}