Kor is a tool to discover unused Kubernetes resources. Currently, Kor can identify and list unused:

• ConfigMaps
• Secrets
• Services
• ServiceAccounts
• Deployments
• StatefulSets
• Roles
• HPAs
• PVCs
• Ingresses
• PDBs

Download the binary for your operating system from the releases page and add it to your system's PATH.

For macOS users, you can install Kor using Homebrew:

brew install kor

Install the binary to your $GOBIN or $GOPATH/bin:

go install github.com/yonahd/kor@latest

Run a container with your kubeconfig mounted:

docker run --rm -i yonahdissen/kor

docker run --rm -i -v "/path/to/.kube/config:/root/.kube/config" yonahdissen/kor all

Run as a cronjob in your Cluster

helm upgrade -i kor \
    --namespace kor \
    --create-namespace \
    ./charts/kor

For more information see in cluster usage

Kor provides various subcommands to identify and list unused resources. The available commands are:

• all - Gets all unused resources for the specified namespace or all namespaces.
• configmap - Gets unused ConfigMaps for the specified namespace or all namespaces.
• secret - Gets unused Secrets for the specified namespace or all namespaces.
• services - Gets unused Services for the specified namespace or all namespaces.
• serviceaccount - Gets unused ServiceAccounts for the specified namespace or all namespaces.
• deployments - Gets unused Deployments for the specified namespace or all namespaces.
• statefulsets - Gets unused StatefulSets for the specified namespace or all namespaces.
• role - Gets unused Roles for the specified namespace or all namespaces.
• hpa - Gets unused HPAs for the specified namespace or all namespaces.
• pvc - Gets unused PVCs for the specified namespace or all namespaces.
• ingress - Gets unused Ingresses for the specified namespace or all namespaces.
• pdb - Gets unused PDBs for the specified namespace or all namespaces.
• exporter - Export Prometheus metrics.

-e, --exclude-namespaces string   Namespaces to be excluded, split by comma. Example: --exclude-namespace ns1,ns2,ns3. If --include-namespace is set, --exclude-namespaces will be ignored.
-h, --help                        help for kor
-n, --include-namespaces string   Namespaces to run on, split by comma. Example: --include-namespace ns1,ns2,ns3.
-k, --kubeconfig string           Path to kubeconfig file (optional)
    --output string               Output format (table or json) (default "table")
    --slack-auth-token string     Slack auth token to send notifications to. --slack-auth-token requires --slack-channel to be set.
    --slack-channel string        Slack channel to send notifications to. --slack-channel requires --slack-auth-token to be set.
    --slack-webhook-url string    Slack webhook URL to send notifications to

To use a specific subcommand, run kor [subcommand] [flags].

kor all --namespace my-namespace

For more information about each subcommand and its available flags, you can use the --help flag.

kor [subcommand] --help

The resources labeled with "kor/used = true" will be ignored by kor even if they are unused. You can add this label to resources you want to ignore.

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.

import (
    "github.com/yonahd/kor/pkg/kor"
)

func main() {
    myNamespaces := kor.IncludeExcludeLists{
        IncludeListStr: "my-namespace1, my-namespace2",
    }
    outputFormat := "json" // Set to "json" for JSON output

    if outputFormat == "json" {
        jsonResponse, err := kor.GetUnusedDeploymentsStructured(myNamespaces, kubeconfig, "json")
        if err != nil {
            // Handle error
        }
        // Process the JSON response
        // ...
    } else {
        kor.GetUnusedDeployments(namespace)
    }
}

To use this tool inside the cluster running as a CronJob and sending the results to a Slack Webhook as raw text(has characters limits of 4000) or to a Slack channel by uploading a file(recommended), you can use the following commands:

# Send to a Slack webhook as raw text
helm upgrade -i kor \
    --namespace kor \
    --create-namespace \
    --set cronJob.slackWebhookUrl=<slack-webhook-url> \
    ./charts/kor

# Send to a Slack channel by uploading a file
helm upgrade -i kor \
    --namespace kor \
    --create-namespace \
    --set cronJob.slackChannel=<slack-channel> \
    --set cronJob.slackToken=<slack-token> \
    ./charts/kor

Note: To send it to Slack as a file it's required to set the slackToken and slackChannel values.

It's set to run every Monday at 1 a.m. by default. You can change the schedule by setting the cronJob.schedule value.

helm upgrade -i kor \
    --namespace kor \
    --create-namespace \
    --set cronJob.slackChannel=<slack-channel> \
    --set cronJob.slackToken=<slack-token> \
    --set cronJob.schedule="0 1 * * 1" \
    ./charts/kor

Contributions are welcome! If you encounter any bugs or have suggestions for improvements, please open an issue in the issue tracker.

This open-source project is available under the MIT License. Feel free to use, modify, and distribute it as per the terms of the license.