pkg/karmadactl: unit test cordon

In this commit, we unit test cordon on karmadactl client
making sure the cordon/uncordon working as expected on a given cluster.

Signed-off-by: Mohamed Awnallah <[email protected]>

pkg/karmadactl/cordon/cordon_test.go

@@ -0,0 +1,263 @@
+/*
+Copyright 2024 The Karmada 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 cordon
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"os"
+	"reflect"
+	"strings"
+	"testing"
+
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	cmdutil "k8s.io/kubectl/pkg/cmd/util"
+
+	clusterv1alpha1 "github.com/karmada-io/karmada/pkg/apis/cluster/v1alpha1"
+	karmadaclientset "github.com/karmada-io/karmada/pkg/generated/clientset/versioned"
+	fakekarmadaclient "github.com/karmada-io/karmada/pkg/generated/clientset/versioned/fake"
+	"github.com/karmada-io/karmada/pkg/karmadactl/util"
+)
+
+type testFactory struct {
+	cmdutil.Factory
+	client karmadaclientset.Interface
+}
+
+func (t testFactory) KarmadaClientSet() (karmadaclientset.Interface, error) {
+	return t.client, nil
+}
+
+func (t testFactory) FactoryForMemberCluster(string) (cmdutil.Factory, error) {
+	panic("not implemented")
+}
+
+type fTaintCondition func(cluster *clusterv1alpha1.Cluster) error
+
+var fTCordonCondition = func(cluster *clusterv1alpha1.Cluster) error {
+	if len(cluster.Spec.Taints) == 0 {
+		return fmt.Errorf("expected one noschedule taint for cluster %s, but got empty taints", cluster.GetName())
+	}
+	taintExpected := corev1.Taint{
+		Key:    clusterv1alpha1.TaintClusterUnscheduler,
+		Effect: corev1.TaintEffectNoSchedule,
+	}
+	if !reflect.DeepEqual(cluster.Spec.Taints[0], taintExpected) {
+		return fmt.Errorf("expected taint %v, but got %v", taintExpected, cluster.Spec.Taints[0])
+	}
+	return nil
+}
+
+var fTUncordonCondition = func(cluster *clusterv1alpha1.Cluster) error {
+	if len(cluster.Spec.Taints) != 0 {
+		return fmt.Errorf("expected no taints for cluster %s, but got %d taints", cluster.GetName(), len(cluster.Spec.Taints))
+	}
+	return nil
+}
+
+func TestRunCordonOrUncordon(t *testing.T) {
+	clusterName := "test-cluster"
+	tests := []struct {
+		name                string
+		desiredCordonStatus int
+		f                   util.Factory
+		opts                *CommandCordonOption
+		prep                func(f util.Factory, opts *CommandCordonOption, desiredCordonStatus int) error
+		verify              func(util.Factory) error
+		wantErr             bool
+		logMsg              string
+	}{
+		{
+			name:                "RunCordonOrUncordon_CordonUncordonedCluster_ClusterCordoned",
+			desiredCordonStatus: DesiredCordon,
+			f:                   testFactory{client: fakekarmadaclient.NewSimpleClientset()},
+			opts:                &CommandCordonOption{ClusterName: clusterName},
+			prep: func(f util.Factory, _ *CommandCordonOption, _ int) error {
+				return prepClusterCreation(f, clusterName)
+			},
+			verify: func(f util.Factory) error {
+				return verifyClusterCordoned(f, clusterName, fTCordonCondition)
+			},
+			wantErr: false,
+			logMsg:  fmt.Sprintf("%s cluster cordoned", clusterName),
+		},
+		{
+			name:                "RunCordonOrUncordon_CordonCordonedCluster_ClusterAlreadyCordoned",
+			desiredCordonStatus: DesiredCordon,
+			f:                   testFactory{client: fakekarmadaclient.NewSimpleClientset()},
+			opts:                &CommandCordonOption{ClusterName: clusterName},
+			prep: func(f util.Factory, opts *CommandCordonOption, desiredCordonStatus int) error {
+				if err := prepClusterCreation(f, clusterName); err != nil {
+					return err
+				}
+				if err := RunCordonOrUncordon(desiredCordonStatus, f, *opts); err != nil {
+					return fmt.Errorf("failed to cordon cluster %s, got error: %v", clusterName, err)
+				}
+				return nil
+			},
+			verify:  func(util.Factory) error { return nil },
+			wantErr: false,
+			logMsg:  fmt.Sprintf("%s cluster already cordoned", clusterName),
+		},
+		{
+			name:                "RunCordonOrUncordon_UncordonCordonedCluster_ClusterUncordoned",
+			desiredCordonStatus: DesiredUnCordon,
+			f:                   testFactory{client: fakekarmadaclient.NewSimpleClientset()},
+			opts:                &CommandCordonOption{ClusterName: clusterName},
+			prep: func(f util.Factory, opts *CommandCordonOption, _ int) error {
+				if err := prepClusterCreation(f, clusterName); err != nil {
+					return err
+				}
+				if err := RunCordonOrUncordon(DesiredCordon, f, *opts); err != nil {
+					return fmt.Errorf("failed to cordon cluster %s, got error: %v", clusterName, err)
+				}
+				return nil
+			},
+			verify: func(f util.Factory) error {
+				return verifyClusterCordoned(f, clusterName, fTUncordonCondition)
+			},
+			wantErr: false,
+			logMsg:  fmt.Sprintf("%s cluster uncordoned", clusterName),
+		},
+		{
+			name:                "RunCordonOrUncordon_UncordonUncordonedCluster_ClusterAlreadyUncordoned",
+			desiredCordonStatus: DesiredUnCordon,
+			f:                   testFactory{client: fakekarmadaclient.NewSimpleClientset()},
+			opts:                &CommandCordonOption{ClusterName: clusterName},
+			prep: func(f util.Factory, _ *CommandCordonOption, _ int) error {
+				return prepClusterCreation(f, clusterName)
+			},
+			verify:  func(util.Factory) error { return nil },
+			wantErr: false,
+			logMsg:  fmt.Sprintf("%s cluster already uncordoned", clusterName),
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			if test.logMsg != "" {
+				r, w, oldStdout, err := prepLogMsgWatcher()
+				if err != nil {
+					t.Fatal(err)
+				}
+				defer func() {
+					if err := verifyMsg(r, w, oldStdout, test.logMsg); err != nil {
+						t.Error(err)
+					}
+				}()
+			}
+			if err := test.prep(test.f, test.opts, test.desiredCordonStatus); err != nil {
+				t.Fatalf("failed to prep test environment, got: %v", err)
+			}
+			err := RunCordonOrUncordon(test.desiredCordonStatus, test.f, *test.opts)
+			if err == nil && test.wantErr {
+				t.Fatal("expected an error, but got none")
+			}
+			if err != nil && !test.wantErr {
+				t.Errorf("unexpected error, got: %v", err)
+			}
+			if err := test.verify(test.f); err != nil {
+				t.Errorf("failed to verify the cordon/uncordon, got: %v", err)
+			}
+		})
+	}
+}
+
+// verifyClusterCordoned verifies if the cluster with the given name is cordoned
+// by checking its taint condition using the provided factory and condition function.
+// It returns an error if the cluster retrieval fails or the condition check fails.
+func verifyClusterCordoned(f util.Factory, clusterName string, fTCondition fTaintCondition) error {
+	client, err := f.KarmadaClientSet()
+	if err != nil {
+		return err
+	}
+	cluster, err := client.ClusterV1alpha1().Clusters().Get(context.TODO(), clusterName, metav1.GetOptions{})
+	if err != nil {
+		return fmt.Errorf("failed to get cluster %s, got error: %v", clusterName, err)
+	}
+	return fTCondition(cluster)
+}
+
+// verifyMsg checks if the expected message is in the captured stdout output.
+// Restores os.Stderr after verification and returns an error if the message is missing.
+func verifyMsg(r, w *os.File, oldStdOut *os.File, msgExpected string) error {
+	gotMsg, err := closeAndReadStdOut(r, w)
+	if err != nil {
+		return err
+	}
+	if !strings.Contains(gotMsg, msgExpected) {
+		return fmt.Errorf("expected message %s to be in %s", msgExpected, gotMsg)
+	}
+	os.Stdout = oldStdOut
+	return nil
+}
+
+// closeAndReadStdOut closes the writer and reads from the reader to capture stdout output.
+// Returns the output as a string and an error if reading fails.
+func closeAndReadStdOut(r *os.File, w *os.File) (string, error) {
+	// Close the writer to finish the capture.
+	w.Close()
+
+	// Read the captured output from the pipe.
+	var buf bytes.Buffer
+	_, err := buf.ReadFrom(r)
+	if err != nil {
+		return "", fmt.Errorf("failed to read from pipe: %v", err)
+	}
+
+	output := buf.String()
+	return output, err
+}
+
+// prepLogMsgWatcher redirects os.Stdout to a pipe for capturing messages.
+// Returns the pipe's reader and writer, the original os.Stdout, and an error.
+func prepLogMsgWatcher() (*os.File, *os.File, *os.File, error) {
+	r, w, err := watchStdOut()
+	if err != nil {
+		return nil, nil, nil, fmt.Errorf("failed to watch stdError, got: %v", err)
+	}
+	oldStdout := os.Stdout
+	os.Stdout = w
+	return r, w, oldStdout, err
+}
+
+// watchStdOut creates a pipe to capture os.Stdout. Returns the pipe's reader, writer, and an error.
+func watchStdOut() (*os.File, *os.File, error) {
+	r, w, err := os.Pipe()
+	if err != nil {
+		return nil, nil, fmt.Errorf("failed to create pipe: %v", err)
+	}
+	return r, w, err
+}
+
+// prepClusterCreation creates a new cluster with the given name using the provided factory.
+// It returns an error if the cluster creation fails.
+func prepClusterCreation(f util.Factory, clusterName string) error {
+	client, err := f.KarmadaClientSet()
+	if err != nil {
+		return err
+	}
+	testCluster := &clusterv1alpha1.Cluster{
+		ObjectMeta: metav1.ObjectMeta{Name: clusterName},
+	}
+	_, err = client.ClusterV1alpha1().Clusters().Create(context.TODO(), testCluster, metav1.CreateOptions{})
+	if err != nil {
+		return fmt.Errorf("failed to create cluster %s, got: %v", testCluster, err)
+	}
+	return nil
+}