polish

Signed-off-by: Ahmet Alp Balkan <[email protected]>

Author: ahmetb

README.md

@@ -3,12 +3,37 @@
 A kubectl plugin to explore ownership relationships between Kubernetes objects
 through ownersReferences on them.
 
+## Installation
+
+> **NOTE:** This is still not working as I'm packaging it for Krew.
+
+Use [krew](https://sigs.k8s.io/krew) plugin manager to install
+
+    kubectl krew install tree
+    kubectl tree --help
+
+## Demo
+
+Example (Deployment):
+
+![example Kubernetes deployment object hierarchy](assets/example-1.png)
+
+Example (Knative Service):
+
+![example Kubernetes deployment object hierarchy](assets/example-2.png)
+
 ## Author
 
-Ahmet Alp Balkan [@ahmetb](https://twitter.com/ahmetb). Inpired by
-@nimakaviani's knative-inspect tool.
+Ahmet Alp Balkan [@ahmetb](https://twitter.com/ahmetb).
+
+**Special acknowledgement:** This tool is heavily inspired by @nimakaviani's
+[knative-inspect](https://github.com/nimakaviani/knative-inspect/) as it's a
+generalized version of it.
 
 ## License
 
 Apache 2.0. See [LICENSE](./LICENSE).
 
+---
+
+This is not an official Google project.

assets/example-1.png

@@ -85,6 +85,10 @@ func contains(v []string, s string) bool {
 func apiNames(a metav1.APIResource, gv schema.GroupVersion) []string {
 	var out []string
 	singularName := a.SingularName
+	if singularName == "" {
+		// TODO(ahmetb): sometimes SingularName is empty (e.g. Deployment), use lowercase Kind as fallback - investigate why
+		singularName = strings.ToLower(a.Kind)
+	}
 	pluralName := a.Name
 	shortNames := a.ShortNames
 	names := append([]string{singularName, pluralName}, shortNames...)

assets/example-2.png

@@ -28,7 +28,7 @@ var cf *genericclioptions.ConfigFlags
 
 // rootCmd represents the base command when called without any subcommands
 var rootCmd = &cobra.Command{
-	Use:          "kubectl tree",
+	Use:          "kubectl tree KIND NAME",
 	SilenceUsage: true, // for when RunE returns an error
 	Short:        "Show sub-resources of the Kubernetes object",
 	Example: "  kubectl tree deployment my-app\n" +
@@ -66,7 +66,7 @@ func run(cmd *cobra.Command, args []string) error {
 		for _, a := range apiRes {
 			names = append(names, fullAPIName(a))
 		}
-		return fmt.Errorf("ambiguous kind %q. use one of these to disambiguate: [%s]", kind,
+		return fmt.Errorf("ambiguous kind %q. use one of these as the KIND disambiguate: [%s]", kind,
 			strings.Join(names, ", "))
 	}
 

cmd/kubectl-tree/apis.go

@@ -25,6 +25,7 @@ var (
 // treeView prints object hierarchy to out stream.
 func treeView(out io.Writer, objs objectDirectory, obj unstructured.Unstructured) {
 	tbl := uitable.New()
+	tbl.Separator = "  "
 	tbl.AddRow("NAMESPACE", "NAME", "READY", "REASON")
 	treeViewInner("", tbl, objs, obj)
 	fmt.Fprintln(out, tbl)