From a43c12ee95ad33beb19d36cb6291d828aa0919b6 Mon Sep 17 00:00:00 2001
From: Arunvel Sriram <arunvelsriram@gmail.com>
Date: Mon, 12 Nov 2018 00:10:58 +0530
Subject: [PATCH] Implement renaming context

---
 pkg/kubeconfig/kubeconfig.go      | 41 +++++++++++++++++-------
 pkg/kubeconfig/kubeconfig_test.go | 52 +++++++++++++++++++++++++++++++
 2 files changed, 81 insertions(+), 12 deletions(-)

diff --git a/pkg/kubeconfig/kubeconfig.go b/pkg/kubeconfig/kubeconfig.go
index cf8f142..98dc358 100644
--- a/pkg/kubeconfig/kubeconfig.go
+++ b/pkg/kubeconfig/kubeconfig.go
@@ -31,11 +31,6 @@ func (k KubeConfig) Delete(context string) error {
 // regional Kubernetes cluster
 func (k KubeConfig) AddRegionalCluster(project string, cluster string, region string, context string) error {
 	kubeconfig := path.Join(k.dir, context)
-	envs := []string{
-		"CLOUDSDK_CONTAINER_USE_V1_API_CLIENT=false",
-		"CLOUDSDK_CONTAINER_USE_V1_API=false",
-		fmt.Sprintf("KUBECONFIG=%s", kubeconfig),
-	}
 	args := []string{
 		"beta",
 		"container",
@@ -45,8 +40,12 @@ func (k KubeConfig) AddRegionalCluster(project string, cluster string, region st
 		fmt.Sprintf("--region=%s", region),
 		fmt.Sprintf("--project=%s", project),
 	}
-	_, err := k.commander.Execute("gcloud", args, envs)
-	if err != nil {
+	envs := []string{
+		"CLOUDSDK_CONTAINER_USE_V1_API_CLIENT=false",
+		"CLOUDSDK_CONTAINER_USE_V1_API=false",
+		fmt.Sprintf("KUBECONFIG=%s", kubeconfig),
+	}
+	if _, err := k.commander.Execute("gcloud", args, envs); err != nil {
 		return err
 	}
 
@@ -57,9 +56,6 @@ func (k KubeConfig) AddRegionalCluster(project string, cluster string, region st
 // zonal Kubernetes cluster
 func (k KubeConfig) AddZonalCluster(project string, cluster string, zone string, context string) error {
 	kubeconfig := path.Join(k.dir, context)
-	envs := []string{
-		fmt.Sprintf("KUBECONFIG=%s", kubeconfig),
-	}
 	args := []string{
 		"container",
 		"clusters",
@@ -68,8 +64,29 @@ func (k KubeConfig) AddZonalCluster(project string, cluster string, zone string,
 		fmt.Sprintf("--zone=%s", zone),
 		fmt.Sprintf("--project=%s", project),
 	}
-	_, err := k.commander.Execute("gcloud", args, envs)
-	if err != nil {
+	envs := []string{
+		fmt.Sprintf("KUBECONFIG=%s", kubeconfig),
+	}
+	if _, err := k.commander.Execute("gcloud", args, envs); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// RenameContext renames a Kubernetes context
+func (k KubeConfig) RenameContext(oldCtx string, newCtx string) error {
+	kubeconfig := path.Join(k.dir, newCtx)
+	args := []string{
+		"config",
+		"rename-context",
+		oldCtx,
+		newCtx,
+	}
+	envs := []string{
+		fmt.Sprintf("KUBECONFIG=%s", kubeconfig),
+	}
+	if _, err := k.commander.Execute("kubectl", args, envs); err != nil {
 		return err
 	}
 
diff --git a/pkg/kubeconfig/kubeconfig_test.go b/pkg/kubeconfig/kubeconfig_test.go
index 18b21d5..03d5c87 100644
--- a/pkg/kubeconfig/kubeconfig_test.go
+++ b/pkg/kubeconfig/kubeconfig_test.go
@@ -203,3 +203,55 @@ func TestAddZonalCluster(t *testing.T) {
 		assert.EqualError(t, err, "some error")
 	})
 }
+
+func TestRenameContext(t *testing.T) {
+	t.Run("should rename a context", func(t *testing.T) {
+		ctrl := gomock.NewController(t)
+		defer ctrl.Finish()
+
+		mockFS := mock.NewFileSystem(ctrl)
+		mockFS.EXPECT().HomeDir().Return("/Users/test", nil)
+
+		mockCmdr := mock.NewCommander(ctrl)
+		args := []string{
+			"config",
+			"rename-context",
+			"old-context-name",
+			"new-context-name",
+		}
+		envs := []string{
+			"KUBECONFIG=/Users/test/.kube/configs/new-context-name",
+		}
+		mockCmdr.EXPECT().Execute("kubectl", args, envs).Return("Context renamed", nil)
+
+		kubeCfg, _ := kubeconfig.New(mockFS, mockCmdr)
+		err := kubeCfg.RenameContext("old-context-name", "new-context-name")
+
+		assert.Nil(t, err)
+	})
+
+	t.Run("should return error if renaming context fails", func(t *testing.T) {
+		ctrl := gomock.NewController(t)
+		defer ctrl.Finish()
+
+		mockFS := mock.NewFileSystem(ctrl)
+		mockFS.EXPECT().HomeDir().Return("/Users/test", nil)
+
+		mockCmdr := mock.NewCommander(ctrl)
+		args := []string{
+			"config",
+			"rename-context",
+			"old-context-name",
+			"new-context-name",
+		}
+		envs := []string{
+			"KUBECONFIG=/Users/test/.kube/configs/new-context-name",
+		}
+		mockCmdr.EXPECT().Execute("kubectl", args, envs).Return("", fmt.Errorf("some error"))
+
+		kubeCfg, _ := kubeconfig.New(mockFS, mockCmdr)
+		err := kubeCfg.RenameContext("old-context-name", "new-context-name")
+
+		assert.EqualError(t, err, "some error")
+	})
+}