SD

Validate Kubernetes (k8s) yaml files online.

This project was inspired by and based on garethr’s kubeval. After attending his talk at Kubecon in December 2017 I put this together to make use of kubeval to perform validations by pasting into a web interface. Garethr’s kubeval already has a nice CLI you can use as part of a CI/CD system, and kubevalonline supplements this tool for use during the development process.

Given a kubernetes configuration file with an invalid value such as:

apiVersion: v1
kind: Service
metadata:
  name: redis-master
  labels:
    app: redis
    tier: backend
    role: master
spec:
  ports:
    # the port that this service should serve on
  - port: sds
    targetPort: 6379
  selector:
    app: redis
    tier: backend
    role: master

kubeval recognizes that port values should be integer type and not string type then responds with an error:

{
  "Results": [
    {
      "Kind": "Service",
      "Success": false,
      "Errors": [
        "Invalid type. Expected: integer, given: string"
      ]
    }
  ]
}

kubectl run provides a --dry-run flag which can also be used to partially verify that a declaration is valid, but kubeval provides additional information that is valuable when debugging. A handy tool for the kubernaut!

The source code is hosted on github. The image can be pulled from dockerhub.

Travis CI and coveralls handle the build and code coverage.