Add flux tree command

The `flux tree kustomization` command prints the resources reconciled by the given Kustomization.

Signed-off-by: Stefan Prodan <stefan.prodan@gmail.com>

cmd/flux/tree_kustomization.go

@@ -0,0 +1,138 @@
+/*
+Copyright 2021 The Flux 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 main
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/fluxcd/flux2/internal/tree"
+	"github.com/fluxcd/flux2/internal/utils"
+	kustomizev1 "github.com/fluxcd/kustomize-controller/api/v1beta2"
+	"github.com/spf13/cobra"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"sigs.k8s.io/cli-utils/pkg/object"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+)
+
+var treeKsCmd = &cobra.Command{
+	Use:     "kustomization [name]",
+	Aliases: []string{"ks", "kustomization"},
+	Short:   "Print the resource inventory of a Kustomization",
+	Long:    `The tree command prints the resource list reconciled by a Kustomization.'`,
+	Example: `  # Print the resources managed by the root Kustomization
+  flux tree kustomization flux-system
+
+  # Print the Flux resources managed by the root Kustomization
+  flux tree kustomization flux-system --compact`,
+	RunE: treeKsCmdRun,
+}
+
+type TreeKsFlags struct {
+	compact bool
+}
+
+var treeKsArgs TreeKsFlags
+
+func init() {
+	treeKsCmd.Flags().BoolVar(&treeKsArgs.compact, "compact", false, "list Flux resources only.")
+	treeCmd.AddCommand(treeKsCmd)
+}
+
+func treeKsCmdRun(cmd *cobra.Command, args []string) error {
+	if len(args) < 1 {
+		return fmt.Errorf("kustomization name is required")
+	}
+	name := args[0]
+
+	ctx, cancel := context.WithTimeout(context.Background(), rootArgs.timeout)
+	defer cancel()
+
+	kubeClient, err := utils.KubeClient(rootArgs.kubeconfig, rootArgs.kubecontext)
+	if err != nil {
+		return err
+	}
+
+	k := &kustomizev1.Kustomization{}
+	err = kubeClient.Get(ctx, client.ObjectKey{
+		Namespace: rootArgs.namespace,
+		Name:      name,
+	}, k)
+	if err != nil {
+		return err
+	}
+
+	kMeta, err := object.CreateObjMetadata(k.Namespace, k.Name,
+		schema.GroupKind{Group: kustomizev1.GroupVersion.Group, Kind: kustomizev1.KustomizationKind})
+	if err != nil {
+		return err
+	}
+
+	kTree := tree.New(kMeta)
+	err = treeKustomization(ctx, kTree, k, kubeClient, treeKsArgs.compact)
+	if err != nil {
+		return err
+	}
+
+	rootCmd.Println(kTree.Print())
+
+	return nil
+}
+
+func treeKustomization(ctx context.Context, tree tree.ObjMetadataTree, item *kustomizev1.Kustomization, kubeClient client.Client, compact bool) error {
+	if item.Status.Inventory == nil || len(item.Status.Inventory.Entries) == 0 {
+		return nil
+	}
+
+	for _, entry := range item.Status.Inventory.Entries {
+		objMetadata, err := object.ParseObjMetadata(entry.ID)
+		if err != nil {
+			return err
+		}
+
+		if compact && !strings.Contains(objMetadata.GroupKind.Group, "toolkit.fluxcd.io") {
+			continue
+		}
+
+		if objMetadata.GroupKind.Group == kustomizev1.GroupVersion.Group &&
+			objMetadata.GroupKind.Kind == kustomizev1.KustomizationKind &&
+			objMetadata.Namespace == item.Namespace &&
+			objMetadata.Name == item.Name {
+			continue
+		}
+
+		ks := tree.Add(objMetadata)
+		if objMetadata.GroupKind.Group == kustomizev1.GroupVersion.Group &&
+			objMetadata.GroupKind.Kind == kustomizev1.KustomizationKind {
+			k := &kustomizev1.Kustomization{}
+			err = kubeClient.Get(ctx, client.ObjectKey{
+				Namespace: objMetadata.Namespace,
+				Name:      objMetadata.Name,
+			}, k)
+			if err != nil {
+				return fmt.Errorf("failed to find object: %w", err)
+			}
+			err := treeKustomization(ctx, ks, k, kubeClient, compact)
+			if err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}