Merge pull request #268 from kinvolk/surajssd/uninstall-component

Add support for `lokoctl component delete`

cli/cmd/component-delete.go

@@ -0,0 +1,184 @@
+// Copyright 2020 The Lokomotive 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 cmd
+
+import (
+	"fmt"
+	"strings"
+
+	log "github.com/sirupsen/logrus"
+	"github.com/spf13/cobra"
+	"helm.sh/helm/v3/pkg/action"
+	"k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+
+	"github.com/kinvolk/lokomotive/pkg/components"
+	"github.com/kinvolk/lokomotive/pkg/components/util"
+	"github.com/kinvolk/lokomotive/pkg/k8sutil"
+)
+
+var componentDeleteCmd = &cobra.Command{
+	Use:   "delete",
+	Short: "Delete an installed component",
+	Long: `Delete a component.
+When run with no arguments, all components listed in the configuration are deleted.`,
+	Run: runDelete,
+}
+
+var deleteNamespace bool
+
+// nolint:gochecknoinits
+func init() {
+	componentCmd.AddCommand(componentDeleteCmd)
+	pf := componentDeleteCmd.PersistentFlags()
+	pf.BoolVarP(&deleteNamespace, "delete-namespace", "", false, "Delete namespace with component.")
+}
+
+func runDelete(cmd *cobra.Command, args []string) {
+	contextLogger := log.WithFields(log.Fields{
+		"command": "lokoctl component delete",
+		"args":    args,
+	})
+
+	lokoCfg, diags := getLokoConfig()
+	if len(diags) > 0 {
+		contextLogger.Fatal(diags)
+	}
+
+	componentsToDelete := make([]string, len(args))
+	copy(componentsToDelete, args)
+
+	if len(args) == 0 {
+		componentsToDelete = make([]string, len(lokoCfg.RootConfig.Components))
+
+		for i, component := range lokoCfg.RootConfig.Components {
+			componentsToDelete[i] = component.Name
+		}
+	}
+
+	componentsObjects := make([]components.Component, len(componentsToDelete))
+
+	for i, componentName := range componentsToDelete {
+		compObj, err := components.Get(componentName)
+		if err != nil {
+			contextLogger.Fatal(err)
+		}
+
+		componentsObjects[i] = compObj
+	}
+
+	if !askForConfirmation(
+		fmt.Sprintf(
+			"The following components will be deleted:\n\t%s\n\nAre you sure you want to proceed?",
+			strings.Join(componentsToDelete, "\n\t"),
+		),
+	) {
+		contextLogger.Info("Components deletion cancelled.")
+		return
+	}
+
+	kubeconfig, err := getKubeconfig()
+	if err != nil {
+		contextLogger.Fatalf("Error in finding kubeconfig file: %s", err)
+	}
+
+	if err := deleteComponents(kubeconfig, componentsObjects...); err != nil {
+		contextLogger.Fatal(err)
+	}
+}
+
+func deleteComponents(kubeconfig string, componentObjects ...components.Component) error {
+	for _, compObj := range componentObjects {
+		fmt.Printf("Deleting component '%s'...\n", compObj.Metadata().Name)
+
+		if err := deleteHelmRelease(compObj, kubeconfig, deleteNamespace); err != nil {
+			return err
+		}
+
+		fmt.Printf("Successfully deleted component %q!\n", compObj.Metadata().Name)
+	}
+
+	// Add a line to distinguish between info logs and errors, if any.
+	fmt.Println()
+
+	return nil
+}
+
+// deleteComponent deletes a component.
+func deleteHelmRelease(c components.Component, kubeconfig string, deleteNSBool bool) error {
+	name := c.Metadata().Name
+	if name == "" {
+		// This should never fail in real user usage, if this does that means the component was not
+		// created with all the needed information.
+		panic(fmt.Errorf("component name is empty"))
+	}
+
+	ns := c.Metadata().Namespace
+	if ns == "" {
+		// This should never fail in real user usage, if this does that means the component was not
+		// created with all the needed information.
+		panic(fmt.Errorf("component %s namespace is empty", name))
+	}
+
+	cfg, err := util.HelmActionConfig(ns, kubeconfig)
+	if err != nil {
+		return fmt.Errorf("failed preparing helm client: %w", err)
+	}
+
+	history := action.NewHistory(cfg)
+	// Check if the component's release exists. If it does only then proceed to delete.
+	//
+	// Note: It is assumed that this call will return error only when the release does not exist.
+	// The error check is ignored to make `lokoctl component delete ..` idempotent.
+	// We rely on the fact that the 'component name' == 'release name'. Since component's name is
+	// hardcoded and unlikely to change release name won't change as well. And they will be
+	// consistent if installed by lokoctl. So it is highly unlikely that following call will return
+	// any other error than "release not found".
+	if _, err := history.Run(name); err == nil {
+		uninstall := action.NewUninstall(cfg)
+
+		// Ignore the err when we have deleted the release already or it does not exist for some reason.
+		if _, err := uninstall.Run(name); err != nil {
+			return err
+		}
+	}
+
+	if deleteNSBool {
+		if err := deleteNS(ns, kubeconfig); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func deleteNS(ns string, kubeconfig string) error {
+	cs, err := k8sutil.NewClientset(kubeconfig)
+	if err != nil {
+		return err
+	}
+
+	// Delete the manually created namespace which was not created by helm.
+	if err = cs.CoreV1().Namespaces().Delete(ns, &metav1.DeleteOptions{}); err != nil {
+		// Ignore error when the namespace does not exist.
+		if errors.IsNotFound(err) {
+			return nil
+		}
+
+		return err
+	}
+
+	return nil
+}

cli/cmd/root.go

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// Package cmd has code for all the subcommands of lokoctl.
 package cmd
 
 import (

cli/cmd/utils.go

@@ -16,15 +16,17 @@ package cmd
 
 import (
 	"fmt"
+	"os"
+	"path/filepath"
+
 	"github.com/hashicorp/hcl/v2"
-	"github.com/kinvolk/lokomotive/pkg/backend"
-	"github.com/kinvolk/lokomotive/pkg/config"
-	"github.com/kinvolk/lokomotive/pkg/platform"
 	"github.com/mitchellh/go-homedir"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
-	"os"
-	"path/filepath"
+
+	"github.com/kinvolk/lokomotive/pkg/backend"
+	"github.com/kinvolk/lokomotive/pkg/config"
+	"github.com/kinvolk/lokomotive/pkg/platform"
 )
 
 // getConfiguredBackend loads a backend from the given configuration file.

docs/cli/lokoctl_component.md

@@ -24,6 +24,7 @@ Manage components
 
 * [lokoctl](lokoctl.md)	 - Manage Lokomotive clusters
 * [lokoctl component apply](lokoctl_component_apply.md)	 - Deploy or update a component
+* [lokoctl component delete](lokoctl_component_delete.md)	 - Delete an installed component
 * [lokoctl component list](lokoctl_component_list.md)	 - List all available components
 * [lokoctl component render-manifest](lokoctl_component_render-manifest.md)	 - Print the manifests for a component
 

docs/cli/lokoctl_component_delete.md

@@ -0,0 +1,32 @@
+## lokoctl component delete
+
+Delete an installed component
+
+### Synopsis
+
+Delete a component.
+When run with no arguments, all components listed in the configuration are deleted.
+
+```
+lokoctl component delete [flags]
+```
+
+### Options
+
+```
+      --delete-namespace   Delete namespace with component.
+  -h, --help               help for delete
+```
+
+### Options inherited from parent commands
+
+```
+      --kubeconfig string     Path to kubeconfig file, taken from the asset dir if not given, and finally falls back to ~/.kube/config
+      --lokocfg string        Path to lokocfg directory or file (default "./")
+      --lokocfg-vars string   Path to lokocfg.vars file (default "./lokocfg.vars")
+```
+
+### SEE ALSO
+
+* [lokoctl component](lokoctl_component.md)	 - Manage components
+

pkg/components/cert-manager/component.go

@@ -89,6 +89,7 @@ func (c *component) RenderManifests() (map[string]string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name:      name,
 		Namespace: c.Namespace,
 		Helm: components.HelmMetadata{
 			// Cert-manager registers admission webhooks, so we should wait for the webhook to

pkg/components/cluster-autoscaler/component.go

@@ -333,6 +333,7 @@ func (c *component) RenderManifests() (map[string]string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name:      name,
 		Namespace: c.Namespace,
 	}
 }

pkg/components/contour/component.go

@@ -96,6 +96,7 @@ func (c *component) RenderManifests() (map[string]string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name:      name,
 		Namespace: "projectcontour",
 	}
 }

pkg/components/dex/component.go

@@ -380,6 +380,7 @@ func createSecretManifest(path string) (string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name:      name,
 		Namespace: name,
 	}
 }

pkg/components/external-dns/component.go

@@ -143,6 +143,7 @@ func (c *component) RenderManifests() (map[string]string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name:      name,
 		Namespace: c.Namespace,
 	}
 }

pkg/components/flatcar-linux-update-operator/component.go

@@ -54,6 +54,7 @@ func (c *component) RenderManifests() (map[string]string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name:      componentName,
 		Namespace: "reboot-coordinator",
 	}
 }

pkg/components/gangway/component.go

@@ -284,6 +284,7 @@ func (c *component) RenderManifests() (map[string]string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name:      name,
 		Namespace: name,
 	}
 }

pkg/components/httpbin/component.go

@@ -152,6 +152,7 @@ func (c *component) RenderManifests() (map[string]string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name:      name,
 		Namespace: name,
 	}
 }

pkg/components/metadata.go

@@ -17,6 +17,7 @@ package components
 // Metadata is a struct which represents basic information about the component.
 // It may contain information like name, version, dependencies, namespace, source etc.
 type Metadata struct {
+	Name      string
 	Namespace string
 	Helm      HelmMetadata
 }

pkg/components/metallb/component.go

@@ -129,6 +129,7 @@ func (c *component) RenderManifests() (map[string]string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name:      name,
 		Namespace: "metallb-system",
 	}
 }

pkg/components/metrics-server/component.go

@@ -90,6 +90,7 @@ func (c *component) RenderManifests() (map[string]string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name:      name,
 		Namespace: c.Namespace,
 	}
 }

pkg/components/openebs-operator/component.go

@@ -65,6 +65,7 @@ func (c *component) RenderManifests() (map[string]string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name:      name,
 		Namespace: "openebs",
 	}
 }

pkg/components/openebs-storage-class/component.go

@@ -142,6 +142,7 @@ func (c *component) RenderManifests() (map[string]string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name: name,
 		// Return the same namespace which the openebs-operator component is using.
 		Namespace: "openebs",
 	}

pkg/components/prometheus-operator/component.go

@@ -110,6 +110,7 @@ func (c *component) RenderManifests() (map[string]string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name:      name,
 		Namespace: c.Namespace,
 		Helm: components.HelmMetadata{
 			// Prometheus-operator registers admission webhooks, so we should wait for the webhook to

pkg/components/rook-ceph/component.go

@@ -72,6 +72,7 @@ func (c *component) RenderManifests() (map[string]string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name:      name,
 		Namespace: c.Namespace,
 	}
 }

pkg/components/rook/component.go

@@ -87,6 +87,7 @@ func (c *component) RenderManifests() (map[string]string, error) {
 
 func (c *component) Metadata() components.Metadata {
 	return components.Metadata{
+		Name:      name,
 		Namespace: c.Namespace,
 	}
 }