share-now

How to run the application

# use kind to spawn a new cluster
kind create cluster

# apply k8s manifest to local kind cluster
kubectl apply -f k8s/

# admire beautiful json logs
kubectl logs -l app=share-now-evaluator -f

For a faster local development cycle, skip the Pod deployment and run application on the host machine:

go run main.go --kubeconfig ~/.kube/config

The Docker image is automatically built and pushed to https://quay.io/repository/stephanlindauer/share-now.

Update: I just found out, that kind load docker-image my-custom-image exists. :D

How it went

I kept my code relatively simple and strict to just what the code challenge requested. Going further with this project, I would think about the following improvements:

Tests
Prometheus exporter (tracking things like uptime or ratio of uncompliant pods)
For local development and easier deployment into Kubernetes cluster (without the detour through a third-party repository), I would the build image directly in the cluster (in Kaniko for example).
Use client.CoreV1().Pods("").Watch instead of continuously polling for all Pods.
The Problem Statement suggests that there could be a yaml file with configurations for the different evaluation rules. I think it would be cool, to make the application more configurable via this potential config file. I think of something more dynamic like this:

- name: image_prefix
  description: "ensure the pod only uses images prefixed with `bitnami/`"
  output: boolean
  path: ".spec.containers[].image"
  type: "RegEx"
  value: "^bitnami/.*"

The config could also be created as a CRD, but with the current complexity of this tool it seems absurd. :D
Properly configure the Pod this application is running in with health/liveness probes, priorities, resource limits and resource requests and so on.
Think about if this could also be a CronJob resource. After I decided that it only runs every hour, it would be nice to free up those resources in the mean time.
Refine what the evaluator can do. Does it need access to all namespaces?
Should it run in the default namespace?