kube-score

kube-score is a tool that performs static code analysis of your Kubernetes object definitions.

The output is a list of recommendations of what you can improve to make your application more secure and resilient.

You can test kube-score out in the browser with the online demo (source).

Installation

Pre-built releases can be downloaded from the GitHub releases, from Docker Hub, or with homebrew:

brew install kube-score/tap/kube-score

Checks

For a full list of checks, see README_CHECKS.md.

Container limits (should be set)
Pod is targeted by a NetworkPolicy, both egress and ingress rules are recommended
Deployments and StatefulSets should have a PodDisruptionPolicy
Deployments and StatefulSets should have host PodAntiAffinity configured
Container probes, both readiness and liveness checks should be configured, and should not be identical
Container securityContext, run as high number user/group, do not run as root or with privileged root fs
Stable APIs, use a stable API if available (supported: Deployments, StatefulSets, DaemonSet)

Example output

Usage in CI

kube-score can run in your CI/CD environment and will exit with exit code 1 if a critical error has been found. The trigger level can be changed to warning with the --exit-one-on-warning argument.

The input to kube-score should be all applications that you deploy to the same namespace for the best result.

Example with Helm

helm template my-app | kube-score score -

Example with static YAMLs

kube-score score my-app/*.yaml

kube-score score my-app/deployment.yaml my-app/service.yaml

Configuration

Usage of kube-score:
kube-score [action] --flags

Actions:
	score	Checks all files in the input, and gives them a score and recommendations
	list	Prints a CSV list of all available score checks
	version	Print the version of kube-score
	help	Print this message

Flags for score:
      --enable-optional-test strings    Enable an optional test, can be set multiple times
      --exit-one-on-warning             Exit with code 1 in case of warnings
      --help                            Print help
      --ignore-container-cpu-limit      Disables the requirement of setting a container CPU limit
      --ignore-container-memory-limit   Disables the requirement of setting a container memory limit
      --ignore-test strings             Disable a test, can be set multiple times
      --output-format string            Set to 'human', 'json' or 'ci'. If set to ci, kube-score will output the program in a format that is easier to parse by other programs. (default "human")
  -v, --verbose count                   Enable verbose output, can be set multiple times for increased verbosity.

Ignoring a test

Tests can be ignored in the whole run of the program, with the --ignore-test flag.

A test can also be ignored on a per-object basis, by adding the annotation kube-score/ignore to the object. The value should be a comma separated string of the test IDs.

Example:

Testing this object will temporarily disable the service-type test, which warns against using services of type NodePort.

apiVersion: v1
kind: Service
metadata:
  name: node-port-service-with-ignore
  namespace: foospace
  annotations:
    kube-score/ignore: service-type
spec:
  selector:
    app: my-app
  ports:
  - protocol: TCP
    port: 80
    targetPort: 8080
  type: NodePort

Building from source

kube-score requires Go 1.11 or later to build. Clone this repository, and then:

# Build the project
go build github.com/zegl/kube-score/cmd/kube-score

# Run all tests
go test -v github.com/zegl/kube-score/...

Contributing?

Do you want to help out? Take a look at the Contributing Guidelines for more info. 🤩

Pinpin31/kube-score