Support json response and kubeconfig flag (#13)

* Support JSON return in roles command

* Support JSON return in cms command

* Support JSON return in all command

* Support JSON return in all commands

* Small fix Readme

* Reformat JSON response

* Support optional kubeconfig flag

---------

Co-authored-by: Yonah Dissen <ydissen@vmware.com>

README.md

@@ -1,6 +1,6 @@
 # Kor - Kubernetes Orphaned Resources Finder
 
-Kor is a CLI tool to discover unused Kubernetes resources. Currently, Kor can identify and list unused:
+Kor is a tool to discover unused Kubernetes resources. Currently, Kor can identify and list unused:
 - ConfigMaps  
 - Secrets.
 - Services
@@ -28,6 +28,14 @@ Kor provides various subcommands to identify and list unused resources. The avai
 - `statefulsets`: Gets unused service accounts for the specified namespace or all namespaces.
 - `role`: Gets unused roles for the specified namespace or all namespaces.
 
+### Supported Flags
+```
+-h, --help                help for role
+-k, --kubeconfig string   Path to kubeconfig file (optional)
+-n, --namespace string    Namespace to run on
+--output string       Output format (table or json) (default "table")
+```
+
 To use a specific subcommand, run `kor [subcommand] [flags]`.
 
 ```sh
@@ -49,10 +57,35 @@ kor [subcommand] --help
 | Services        | Services with no endpoints                                                                                                                                                                                                         |                                                                                                                              |
 | Deployments     | Deployments with 0 Replicas                                                                                                                                                                                                        |                                                                                                                              |
 | ServiceAccounts | ServiceAccounts unused by pods<br/>ServiceAccounts unused by roleBinding or clusterRoleBinding                                                                                                                                     |                                                                                                                              |
-| Statefulsets    | Statefulsets with no endpoints                                                                                                                                                                                                     |                                                                                                                              |
+| Statefulsets    | Statefulsets with 0 Replicas                                                                                                                                                                                                     |                                                                                                                              |
 | Roles           | Roles not used in roleBinding                                                                                                                                                                                                      |                                                                                                                              |
 
 
+## Import Option
+You can also use kor as a Go library to programmatically discover unused resources. By importing the github.com/yonahd/kor/pkg/kor package, you can call the relevant functions to retrieve unused resources. The library provides the option to get the results in JSON format by specifying the outputFormat parameter.
+
+```go
+import (
+"github.com/yonahd/kor/pkg/kor"
+)
+
+func main() {
+namespace := "my-namespace"
+outputFormat := "json" // Set to "json" for JSON output
+
+    if outputFormat == "json" {
+        jsonResponse, err := kor.GetUnusedDeploymentsJSON(namespace)
+        if err != nil {
+            // Handle error
+        }
+        // Process the JSON response
+        // ...
+    } else {
+        kor.GetUnusedDeployments(namespace)
+    }
+}
+```
+
 
 ## Contributing
 

cmd/kor/all.go

@@ -10,12 +10,18 @@ var allCmd = &cobra.Command{
 	Short: "Gets unused resources",
 	Args:  cobra.ExactArgs(0),
 	Run: func(cmd *cobra.Command, args []string) {
-		kor.GetUnusedAll(namespace)
+		if outputFormat == "json" {
+			kor.GetUnusedAllJSON(namespace, kubeconfig)
+		} else {
+			kor.GetUnusedAll(namespace, kubeconfig)
+		}
 
 	},
 }
 
 func init() {
+	allCmd.PersistentFlags().StringVarP(&kubeconfig, "kubeconfig", "k", "", "Path to kubeconfig file (optional)")
 	allCmd.PersistentFlags().StringVarP(&namespace, "namespace", "n", "", "Namespace to run on")
+	allCmd.PersistentFlags().StringVar(&outputFormat, "output", "table", "Output format (table or json)")
 	rootCmd.AddCommand(allCmd)
 }

cmd/kor/configmaps.go

@@ -11,12 +11,18 @@ var configmapCmd = &cobra.Command{
 	Short:   "Gets unused configmaps",
 	Args:    cobra.ExactArgs(0),
 	Run: func(cmd *cobra.Command, args []string) {
-		kor.GetUnusedConfigmaps(namespace)
+		if outputFormat == "json" {
+			kor.GetUnusedConfigmapsJSON(namespace, kubeconfig)
+		} else {
+			kor.GetUnusedConfigmaps(namespace, kubeconfig)
+		}
 
 	},
 }
 
 func init() {
+	configmapCmd.PersistentFlags().StringVarP(&kubeconfig, "kubeconfig", "k", "", "Path to kubeconfig file (optional)")
 	configmapCmd.PersistentFlags().StringVarP(&namespace, "namespace", "n", "", "Namespace to run on")
+	configmapCmd.PersistentFlags().StringVar(&outputFormat, "output", "table", "Output format (table or json)")
 	rootCmd.AddCommand(configmapCmd)
 }

cmd/kor/deployments.go

@@ -11,12 +11,18 @@ var deployCmd = &cobra.Command{
 	Short:   "Gets unused deployments",
 	Args:    cobra.ExactArgs(0),
 	Run: func(cmd *cobra.Command, args []string) {
-		kor.GetUnusedDeployments(namespace)
+		if outputFormat == "json" {
+			kor.GetUnusedDeploymentsJSON(namespace, kubeconfig)
+		} else {
+			kor.GetUnusedDeployments(namespace, kubeconfig)
+		}
 
 	},
 }
 
 func init() {
+	deployCmd.PersistentFlags().StringVarP(&kubeconfig, "kubeconfig", "k", "", "Path to kubeconfig file (optional)")
 	deployCmd.PersistentFlags().StringVarP(&namespace, "namespace", "n", "", "Namespace to run on")
+	deployCmd.PersistentFlags().StringVar(&outputFormat, "output", "table", "Output format (table or json)")
 	rootCmd.AddCommand(deployCmd)
 }

cmd/kor/roles.go

@@ -10,12 +10,17 @@ var roleCmd = &cobra.Command{
 	Short: "Gets unused roles",
 	Args:  cobra.NoArgs,
 	Run: func(cmd *cobra.Command, args []string) {
-		kor.GetUnusedRoles(namespace)
-
+		if outputFormat == "json" {
+			kor.GetUnusedRolesJSON(namespace, kubeconfig)
+		} else {
+			kor.GetUnusedRoles(namespace, kubeconfig)
+		}
 	},
 }
 
 func init() {
+	roleCmd.PersistentFlags().StringVarP(&kubeconfig, "kubeconfig", "k", "", "Path to kubeconfig file (optional)")
 	roleCmd.PersistentFlags().StringVarP(&namespace, "namespace", "n", "", "Namespace to run on")
+	roleCmd.PersistentFlags().StringVar(&outputFormat, "output", "table", "Output format (table or json)")
 	rootCmd.AddCommand(roleCmd)
 }

cmd/kor/root.go

@@ -17,9 +17,10 @@ var rootCmd = &cobra.Command{
 }
 
 var namespace string
+var outputFormat string
+var kubeconfig string
 
 func Execute() {
-
 	if err := rootCmd.Execute(); err != nil {
 		fmt.Fprintf(os.Stderr, "Error while executing your CLI '%s'", err)
 		os.Exit(1)

cmd/kor/secrets.go

@@ -11,12 +11,18 @@ var secretCmd = &cobra.Command{
 	Short:   "Gets unused secrets",
 	Args:    cobra.NoArgs,
 	Run: func(cmd *cobra.Command, args []string) {
-		kor.GetUnusedSecrets(namespace)
+		if outputFormat == "json" {
+			kor.GetUnusedSecretsJSON(namespace, kubeconfig)
+		} else {
+			kor.GetUnusedSecrets(namespace, kubeconfig)
+		}
 
 	},
 }
 
 func init() {
+	secretCmd.PersistentFlags().StringVarP(&kubeconfig, "kubeconfig", "k", "", "Path to kubeconfig file (optional)")
 	secretCmd.PersistentFlags().StringVarP(&namespace, "namespace", "n", "", "Namespace to run on")
+	secretCmd.PersistentFlags().StringVar(&outputFormat, "output", "table", "Output format (table or json)")
 	rootCmd.AddCommand(secretCmd)
 }

cmd/kor/serviceaccounts.go

@@ -11,12 +11,18 @@ var serviceAccountCmd = &cobra.Command{
 	Short:   "Gets unused service accounts",
 	Args:    cobra.ExactArgs(0),
 	Run: func(cmd *cobra.Command, args []string) {
-		kor.GetUnusedServiceAccounts(namespace)
+		if outputFormat == "json" {
+			kor.GetUnusedServiceAccountsJSON(namespace, kubeconfig)
+		} else {
+			kor.GetUnusedServiceAccounts(namespace, kubeconfig)
+		}
 
 	},
 }
 
 func init() {
+	serviceAccountCmd.PersistentFlags().StringVarP(&kubeconfig, "kubeconfig", "k", "", "Path to kubeconfig file (optional)")
 	serviceAccountCmd.PersistentFlags().StringVarP(&namespace, "namespace", "n", "", "Namespace to run on")
+	serviceAccountCmd.PersistentFlags().StringVar(&outputFormat, "output", "table", "Output format (table or json)")
 	rootCmd.AddCommand(serviceAccountCmd)
 }

cmd/kor/services.go

@@ -11,12 +11,18 @@ var serviceCmd = &cobra.Command{
 	Short:   "Gets unused services",
 	Args:    cobra.ExactArgs(0),
 	Run: func(cmd *cobra.Command, args []string) {
-		kor.GetUnusedServices(namespace)
+		if outputFormat == "json" {
+			kor.GetUnusedServicesJSON(namespace, kubeconfig)
+		} else {
+			kor.GetUnusedServices(namespace, kubeconfig)
+		}
 
 	},
 }
 
 func init() {
+	serviceCmd.PersistentFlags().StringVarP(&kubeconfig, "kubeconfig", "k", "", "Path to kubeconfig file (optional)")
 	serviceCmd.PersistentFlags().StringVarP(&namespace, "namespace", "n", "", "Namespace to run on")
+	serviceCmd.PersistentFlags().StringVar(&outputFormat, "output", "table", "Output format (table or json)")
 	rootCmd.AddCommand(serviceCmd)
 }

cmd/kor/statefulsets.go

@@ -11,12 +11,18 @@ var stsCmd = &cobra.Command{
 	Short:   "Gets unused statefulsets",
 	Args:    cobra.ExactArgs(0),
 	Run: func(cmd *cobra.Command, args []string) {
-		kor.GetUnusedStatefulsets(namespace)
+		if outputFormat == "json" {
+			kor.GetUnusedStatefulsetsJSON(namespace, kubeconfig)
+		} else {
+			kor.GetUnusedStatefulsets(namespace, kubeconfig)
+		}
 
 	},
 }
 
 func init() {
+	stsCmd.PersistentFlags().StringVarP(&kubeconfig, "kubeconfig", "k", "", "Path to kubeconfig file (optional)")
 	stsCmd.PersistentFlags().StringVarP(&namespace, "namespace", "n", "", "Namespace to run on")
+	stsCmd.PersistentFlags().StringVar(&outputFormat, "output", "table", "Output format (table or json)")
 	rootCmd.AddCommand(stsCmd)
 }

pkg/kor/all.go

@@ -1,11 +1,17 @@
 package kor
 
 import (
+	"encoding/json"
 	"fmt"
 	"k8s.io/client-go/kubernetes"
 	"os"
 )
 
+type GetUnusedResourceJSONResponse struct {
+	ResourceType string              `json:"resourceType"`
+	Namespaces   map[string][]string `json:"namespaces"`
+}
+
 type ResourceDiff struct {
 	resourceType string
 	diff         []string
@@ -74,12 +80,12 @@ func getUnusedRoles(kubeClient *kubernetes.Clientset, namespace string) Resource
 	return namespaceSADiff
 }
 
-func GetUnusedAll(namespace string) {
+func GetUnusedAll(namespace string, kubeconfig string) {
 	var kubeClient *kubernetes.Clientset
 	var namespaces []string
 	var allDiffs []ResourceDiff
 
-	kubeClient = GetKubeClient()
+	kubeClient = GetKubeClient(kubeconfig)
 
 	namespaces = SetNamespaceList(namespace, kubeClient)
 	for _, namespace := range namespaces {
@@ -102,3 +108,55 @@ func GetUnusedAll(namespace string) {
 		fmt.Println()
 	}
 }
+
+func GetUnusedAllJSON(namespace string, kubeconfig string) (string, error) {
+	var kubeClient *kubernetes.Clientset
+	var namespaces []string
+
+	kubeClient = GetKubeClient(kubeconfig)
+
+	namespaces = SetNamespaceList(namespace, kubeClient)
+
+	// Create the JSON response object
+	response := make(map[string]map[string][]string)
+
+	for _, namespace := range namespaces {
+		var allDiffs []ResourceDiff
+
+		namespaceCMDiff := getUnusedCMs(kubeClient, namespace)
+		allDiffs = append(allDiffs, namespaceCMDiff)
+
+		namespaceSVCDiff := getUnusedSVCs(kubeClient, namespace)
+		allDiffs = append(allDiffs, namespaceSVCDiff)
+
+		namespaceSecretDiff := getUnusedSecrets(kubeClient, namespace)
+		allDiffs = append(allDiffs, namespaceSecretDiff)
+
+		namespaceSADiff := getUnusedServiceAccounts(kubeClient, namespace)
+		allDiffs = append(allDiffs, namespaceSADiff)
+
+		namespaceDeploymentDiff := getUnusedDeployments(kubeClient, namespace)
+		allDiffs = append(allDiffs, namespaceDeploymentDiff)
+
+		namespaceStatefulsetDiff := getUnusedStatefulsets(kubeClient, namespace)
+		allDiffs = append(allDiffs, namespaceStatefulsetDiff)
+
+		namespaceRoleDiff := getUnusedRoles(kubeClient, namespace)
+		allDiffs = append(allDiffs, namespaceRoleDiff)
+
+		// Store the unused resources for each resource type in the JSON response
+		resourceMap := make(map[string][]string)
+		for _, diff := range allDiffs {
+			resourceMap[diff.resourceType] = diff.diff
+		}
+		response[namespace] = resourceMap
+	}
+
+	// Convert the response object to JSON
+	jsonResponse, err := json.MarshalIndent(response, "", "  ")
+	if err != nil {
+		return "", err
+	}
+
+	return string(jsonResponse), nil
+}

pkg/kor/confimgmaps.go

@@ -2,6 +2,7 @@ package kor
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes"
@@ -121,11 +122,11 @@ func processNamespaceCM(kubeClient *kubernetes.Clientset, namespace string) ([]s
 
 }
 
-func GetUnusedConfigmaps(namespace string) {
+func GetUnusedConfigmaps(namespace string, kubeconfig string) {
 	var kubeClient *kubernetes.Clientset
 	var namespaces []string
 
-	kubeClient = GetKubeClient()
+	kubeClient = GetKubeClient(kubeconfig)
 
 	namespaces = SetNamespaceList(namespace, kubeClient)
 
@@ -140,3 +141,30 @@ func GetUnusedConfigmaps(namespace string) {
 		fmt.Println()
 	}
 }
+
+func GetUnusedConfigmapsJSON(namespace string, kubeconfig string) (string, error) {
+	var kubeClient *kubernetes.Clientset
+	var namespaces []string
+
+	kubeClient = GetKubeClient(kubeconfig)
+	namespaces = SetNamespaceList(namespace, kubeClient)
+	response := make(map[string]map[string][]string)
+
+	for _, namespace := range namespaces {
+		diff, err := processNamespaceCM(kubeClient, namespace)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Failed to process namespace %s: %v\n", namespace, err)
+			continue
+		}
+		resourceMap := make(map[string][]string)
+		resourceMap["ConfigMap"] = diff
+		response[namespace] = resourceMap
+	}
+
+	jsonResponse, err := json.MarshalIndent(response, "", "  ")
+	if err != nil {
+		return "", err
+	}
+
+	return string(jsonResponse), nil
+}