a9s-challenge

This document should serve as a step-by-step guide to running the challenge locally! Hopefully it works as expected 😅

Description

This project was built using the operator-sdk cli tool to get the boilerplate code. It creates a new type Dummy with a single Spec Message. It also sets the message to I'm just a dummy.

I used the operator-sdk to initialize a new project, with domain a9s-interview.com, linked to this repo. I also used the sdk to create a new resource of kind Dummy in the interview group.

I extended the generated controller and type files to accomodate the requirements.

I was also using make generate and make manifests to generate and update the goa dn yaml files managed by the sdk.

• Added scaffolding comments to allow CRUD access to different k8s resources.
• The controller gets the Dummy Resource and sets it's SpecEcho to it's Spec Message.
• It also checks if there is an already existing Pod for the Dummy Resource.
• If the pod exists:
  • the controller sets the Dummy's PodStatus to the pod's Status.Phase
• If the pod does not exist
  • The controller creates a new pod with nginx:latest image and references the Dummy resource
  • It tries to get the Pod from k8s with a retry (every 500ms, for 30s)
  • Finally it updates the Dummy's PodStatus with the pod's Status.Phase

There are some integration test cases added, I leveraged the boilerplate test file internal/controller/suite_test.go. To run the tests, simply run make test. I would have added more cases in a real life scenario!

Requirements

• minikube
• kubectl
• Docker
• Make

Getting Started

Here are the steps I took for running and testing the code:

• Run minikube start to start the cluster
• Run make docker-build docker-push to build the docker image and push it to dockerhub
• Run make deploy to deploy to k8s
• Run make install run to start the app locally (while developing, I used this for faster results)
• Run kubectl apply -f config/samples/dummy.yaml to create the Dummy Resource
• Run kubectl get pods -n a9s-challenge-system to get the pods and their statuses
  • There should be one instance a9s-challenge-controller-manager-<pod-hash> with two ready containers in Running status, this is the pod related to the implemented controller
• Run kubectl describe pod a9s-challenge-controller-manager-<pod-hash> (copy from above) to see the logs from the controller
• Run kubectl get dummy dummy -n default -o yaml (yaml formatting is optional) to see the created Dummy resource
  • It should have a spec message I'm just a dummy
  • It should have a status.specEcho of I'm just a dummy
  • It should have a status.podStatus of Running
• Run kubectl logs dummy-pod -n default to see logs about the pod our controller created