refactor: Rename package client to kube (#135)

Signed-off-by: jannfis <jann@mistrust.net>

2 files changed, 150 insertions, 0 deletions

diff --git a/pkg/kube/kubernetes.go b/pkg/kube/kubernetes.go
new file mode 100644
index 0000000..9b5fcc9
--- /dev/null
+++ b/pkg/kube/kubernetes.go
@@ -0,0 +1,77 @@
+package kube
+
+// Kubernetes client related code
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/argoproj-labs/argocd-image-updater/pkg/metrics"
+
+	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/clientcmd"
+)
+
+type KubernetesClient struct {
+	Clientset kubernetes.Interface
+	Context   context.Context
+}
+
+func NewKubernetesClient(ctx context.Context, client kubernetes.Interface) *KubernetesClient {
+	kc := &KubernetesClient{}
+	kc.Context = ctx
+	kc.Clientset = client
+	return kc
+}
+
+// NewKubernetesClient creates a new Kubernetes client object from given
+// configuration file. If configuration file is the empty string, in-cluster
+// client will be created.
+func NewKubernetesClientFromConfig(ctx context.Context, kubeconfig string) (*KubernetesClient, error) {
+	var config *rest.Config
+	var err error
+
+	if kubeconfig != "" {
+		config, err = clientcmd.BuildConfigFromFlags("", kubeconfig)
+	} else {
+		config, err = rest.InClusterConfig()
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	clientset, err := kubernetes.NewForConfig(config)
+	if err != nil {
+		return nil, err
+	}
+
+	return NewKubernetesClient(ctx, clientset), nil
+}
+
+// GetSecretData returns the raw data from named K8s secret in given namespace
+func (client *KubernetesClient) GetSecretData(namespace string, secretName string) (map[string][]byte, error) {
+	secret, err := client.Clientset.CoreV1().Secrets(namespace).Get(client.Context, secretName, v1.GetOptions{})
+	metrics.Clients().IncreaseK8sClientRequest(1)
+	if err != nil {
+		metrics.Clients().IncreaseK8sClientRequest(1)
+		return nil, err
+	}
+	return secret.Data, nil
+}
+
+// GetSecretField returns the value of a field from named K8s secret in given namespace
+func (client *KubernetesClient) GetSecretField(namespace string, secretName string, field string) (string, error) {
+	secret, err := client.GetSecretData(namespace, secretName)
+	metrics.Clients().IncreaseK8sClientRequest(1)
+	if err != nil {
+		metrics.Clients().IncreaseK8sClientRequest(1)
+		return "", err
+	}
+	if data, ok := secret[field]; !ok {
+		return "", fmt.Errorf("secret '%s/%s' does not have a field '%s'", namespace, secretName, field)
+	} else {
+		return string(data), nil
+	}
+}
diff --git a/pkg/kube/kubernetes_test.go b/pkg/kube/kubernetes_test.go
new file mode 100644
index 0000000..9db9bef
--- /dev/null
+++ b/pkg/kube/kubernetes_test.go
@@ -0,0 +1,73 @@
+package kube
+
+import (
+	"context"
+	"os"
+	"testing"
+
+	"github.com/argoproj-labs/argocd-image-updater/test/fake"
+	"github.com/argoproj-labs/argocd-image-updater/test/fixture"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func Test_NewKubernetesClient(t *testing.T) {
+	t.Run("Get new K8s client for remote cluster instance", func(t *testing.T) {
+		client, err := NewKubernetesClientFromConfig(context.TODO(), "../../test/testdata/kubernetes/config")
+		require.NoError(t, err)
+		assert.NotNil(t, client)
+	})
+
+	t.Run("Get new K8s client for in-cluster instance", func(t *testing.T) {
+		os.Setenv("KUBERNETES_SERVICE_HOST", "127.0.0.1")
+		os.Setenv("KUBERNETES_SERVICE_PORT", "6443")
+		defer os.Setenv("KUBERNETES_SERVICE_HOST", "")
+		defer os.Setenv("KUBERNETES_SERVICE_PORT", "")
+		client, err := NewKubernetesClientFromConfig(context.TODO(), "")
+		// We cannot create /var/run/secrets/kubernetes.io/serviceaccount/token so
+		// we just assume error and look for that path in error message.
+		assert.Errorf(t, err, "open /var/run/secrets/kubernetes.io/serviceaccount/token: no such file or directory")
+		assert.Nil(t, client)
+	})
+}
+
+func Test_GetDataFromSecrets(t *testing.T) {
+	t.Run("Get all data from dummy secret", func(t *testing.T) {
+		secret := fixture.MustCreateSecretFromFile("../../test/testdata/resources/dummy-secret.json")
+		clientset := fake.NewFakeClientsetWithResources(secret)
+		client := &KubernetesClient{Clientset: clientset}
+		data, err := client.GetSecretData("test-namespace", "test-secret")
+		require.NoError(t, err)
+		require.NotNil(t, data)
+		assert.Len(t, data, 1)
+		assert.Equal(t, "argocd", string(data["namespace"]))
+	})
+
+	t.Run("Get string data from dummy secret existing field", func(t *testing.T) {
+		secret := fixture.MustCreateSecretFromFile("../../test/testdata/resources/dummy-secret.json")
+		clientset := fake.NewFakeClientsetWithResources(secret)
+		client := &KubernetesClient{Clientset: clientset}
+		data, err := client.GetSecretField("test-namespace", "test-secret", "namespace")
+		require.NoError(t, err)
+		assert.Equal(t, "argocd", data)
+	})
+
+	t.Run("Get string data from dummy secret non-existing field", func(t *testing.T) {
+		secret := fixture.MustCreateSecretFromFile("../../test/testdata/resources/dummy-secret.json")
+		clientset := fake.NewFakeClientsetWithResources(secret)
+		client := &KubernetesClient{Clientset: clientset}
+		data, err := client.GetSecretField("test-namespace", "test-secret", "nonexisting")
+		require.Error(t, err)
+		require.Empty(t, data)
+	})
+
+	t.Run("Get string data from non-existing secret non-existing field", func(t *testing.T) {
+		secret := fixture.MustCreateSecretFromFile("../../test/testdata/resources/dummy-secret.json")
+		clientset := fake.NewFakeClientsetWithResources(secret)
+		client := &KubernetesClient{Clientset: clientset}
+		data, err := client.GetSecretField("test-namespace", "test", "namespace")
+		require.Error(t, err)
+		require.Empty(t, data)
+	})
+}