add support for the deployment resource

README.md

@@ -1,6 +1,11 @@
 # Kor - Kubernetes Orphaned Resources Finder
 
-Kor is a CLI tool to discover unused Kubernetes resources. Currently, Kor can identify and list unused ConfigMaps and Secrets.
+Kor is a CLI tool to discover unused Kubernetes resources. Currently, Kor can identify and list unused:
+- ConfigMaps  
+- Secrets.
+- Services
+- ServiceAccounts
+- Deployments
 
 ![Kor Screenshot](/images/screenshot.png)
 
@@ -30,10 +35,21 @@ For more information about each subcommand and its available flags, you can use
 kor [subcommand] --help
 ```
 
+## Supported resources and limitations
+
+| Resource        | What it looks for                                                                                                                                                                                                    | Known False Positives                                                                                                        |
+|-----------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------|
+| Configmaps      | - Configmaps used by pods<br/>- Configmaps used by containers <br/>- Configmaps used through volumes <br/>- Configmaps used through environment variables                                                            | Configmaps used by resources which don't explicitly state them in the config.<br/> e.g Grafana dashboards loaded dynamically |
+| Secrets         | - Secrets used by pods<br/>- Secrets used by containers <br/>- Secrets used through volumes <br/>- Secrets used through environment variables<br/>- Secrets used by ingress TLS<br/>-Secrets used by ServiceAccounts |                                                                                                                              |
+| Services        | Services with no endpoints                                                                                                                                                                                           |                                                                                                                              |
+| Deployments     | Deployments with 0 Replicas                                                                                                                                                                                          |                                                                                                                              |
+| ServiceAccounts | ServiceAccounts used by pods                                                                                                                                                                                         |                                                                                                                              |
+
 ## Contributing
 
 Contributions are welcome! If you encounter any bugs or have suggestions for improvements, please open an issue in the [issue tracker](https://github.com/yonahd/kor/issues).
 
 ## License
 
-This project is open-source and available under the [MIT License](LICENSE). Feel free to use, modify, and distribute it as per the terms of the license.
+This project is open-source and available under the [MIT License](LICENSE). Feel free to use, modify, and distribute it as per the terms of the license.
+

cmd/kor/deployments.go

@@ -0,0 +1,22 @@
+package kor
+
+import (
+	"github.com/spf13/cobra"
+	"github.com/yonahd/kor/pkg/kor"
+)
+
+var deployCmd = &cobra.Command{
+	Use:     "deployments",
+	Aliases: []string{"deploy"},
+	Short:   "Gets unused deployments",
+	Args:    cobra.ExactArgs(0),
+	Run: func(cmd *cobra.Command, args []string) {
+		kor.GetUnusedDeployments(namespace)
+
+	},
+}
+
+func init() {
+	deployCmd.PersistentFlags().StringVarP(&namespace, "namespace", "n", "", "Namespace to run on")
+	rootCmd.AddCommand(deployCmd)
+}

pkg/kor/all.go

@@ -47,6 +47,15 @@ func getUnusedServiceAccounts(kubeClient *kubernetes.Clientset, namespace string
 	return namespaceSADiff
 }
 
+func getUnusedDeployments(kubeClient *kubernetes.Clientset, namespace string) ResourceDiff {
+	saDiff, err := ProcessNamespaceDeployments(kubeClient, namespace)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Failed to get %s namespace %s: %v\n", "serviceaccounts", namespace, err)
+	}
+	namespaceSADiff := ResourceDiff{"Deployment", saDiff}
+	return namespaceSADiff
+}
+
 func GetUnusedAll(namespace string) {
 	var kubeClient *kubernetes.Clientset
 	var namespaces []string
@@ -64,6 +73,8 @@ func GetUnusedAll(namespace string) {
 		allDiffs = append(allDiffs, namespaceSecretDiff)
 		namespaceSADiff := getUnusedServiceAccounts(kubeClient, namespace)
 		allDiffs = append(allDiffs, namespaceSADiff)
+		namespaceDeploymentDiff := getUnusedDeployments(kubeClient, namespace)
+		allDiffs = append(allDiffs, namespaceDeploymentDiff)
 		output := FormatOutputAll(namespace, allDiffs)
 		fmt.Println(output)
 		fmt.Println()

pkg/kor/deployments.go

@@ -0,0 +1,56 @@
+package kor
+
+import (
+	"context"
+	"fmt"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+	"os"
+)
+
+func getDeploymentsWithoutReplicas(kubeClient *kubernetes.Clientset, namespace string) ([]string, error) {
+	deploymentsList, err := kubeClient.AppsV1().Deployments(namespace).List(context.TODO(), metav1.ListOptions{})
+	if err != nil {
+		return nil, err
+	}
+
+	var deploymentsWithoutReplicas []string
+
+	for _, deployment := range deploymentsList.Items {
+		if *deployment.Spec.Replicas == 0 {
+			deploymentsWithoutReplicas = append(deploymentsWithoutReplicas, deployment.Name)
+		}
+	}
+
+	return deploymentsWithoutReplicas, nil
+}
+
+func ProcessNamespaceDeployments(clientset *kubernetes.Clientset, namespace string) ([]string, error) {
+	usedServices, err := getDeploymentsWithoutReplicas(clientset, namespace)
+	if err != nil {
+		return nil, err
+	}
+
+	return usedServices, nil
+
+}
+
+func GetUnusedDeployments(namespace string) {
+	var kubeClient *kubernetes.Clientset
+	var namespaces []string
+
+	kubeClient = GetKubeClient()
+
+	namespaces = SetNamespaceList(namespace, kubeClient)
+
+	for _, namespace := range namespaces {
+		diff, err := ProcessNamespaceDeployments(kubeClient, namespace)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Failed to process namespace %s: %v\n", namespace, err)
+			continue
+		}
+		output := FormatOutput(namespace, diff, "Deployments")
+		fmt.Println(output)
+		fmt.Println()
+	}
+}